Publications by authors named "Lance A Mynderse"

76 Publications

The prognostic value, sensitivity, and specificity of multiparametric magnetic resonance imaging before salvage radiotherapy for prostate cancer.

Radiother Oncol 2021 08 21;161:9-15. Epub 2021 May 21.

Department of Radiation Oncology, Mayo Clinic, Rochester, USA.

Aim: To determine the operational characteristics of pelvic magnetic resonance imaging (MRI) prior to salvage radiation therapy (SRT) for biochemically recurrent prostate cancer following radical prostatectomy.

Methods And Materials: We reviewed the medical records of 386 patients who underwent MRI prior to SRT. We assessed associations of pre-SRT MRI findings with biochemical recurrence (BCR), distant metastasis (DM), prostate cancer-specific mortality (PCSM), and salvage androgen deprivation therapy (ADT) use following SRT. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of MRI for detecting local recurrence were also calculated.

Results: Pre-SRT MRI was positive for local recurrence in 216 patients (56%), indeterminate in 46 (12%), and negative in 124 (32%). On univariate analysis, BCR following SRT was significantly less likely for patients with positive (HR: 0.58, 95% CI: 0.42-0.8) or indeterminate (HR: 0.6: 0.36-1) MRI findings, compared to patients with negative imaging (p = 0.003). These associations remained significant on multivariate analysis (p < 0.05) and across pre-SRT PSA groups. For the entire cohort, the sensitivity of MRI for local recurrence was 61.0% (53.5-68.1%), specificity 60.0% (44.3-73.0%), PPV 86.1% (78.9-91.5%) and NPV 27.6% (19.0-37.5%). Sensitivity of MRI was better in men with higher pre-SRT PSA (80.0% for PSA > 1.0), and specificity was improved with lower pre-SRT PSA (73.9% for PSA 0.1-0.5).

Conclusions: Positive or indeterminate MRI findings prior to SRT were associated with improved biochemical control following SRT, across PSA levels. The sensitivity and specificity of MRI for local recurrence were 61% and 58.7%, respectively.
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http://dx.doi.org/10.1016/j.radonc.2021.05.015DOI Listing
August 2021

Non-invasive assessment of urinary bladder compliance using ultrasound: first validation study based on clinical urodynamic study.

Ann Transl Med 2021 Apr;9(7):547

Department of Physiology and Biomedical Engineering, Mayo Clinic College of Medicine & Science, Rochester, MN, USA.

Background: This study aims to validate a recently introduced non-invasive method, ultrasound bladder vibrometry (UBV), for the assessment of detrusor compliance in patients with neurogenic bladders.

Methods: The study was carried out on 79 adult patients with neurogenic bladders (60 male and 19 female). The UBV test was performed on each patient to measure the Lamb wave group velocity ( ) in the anterior bladder wall at every 50mL volume increment throughout the filling phase. Bladder compliance was assessed based on the trend of Lamb wave group velocity squared ( ) versus volume. A compliance index was defined to differentiate between the compliant and non-compliant bladders. Results of the UBV compliance assessment were validated using the readings of the corresponding urodynamic studies as the clinical gold standard.

Results: The Patients' bladders were divided into non-compliant and compliant groups by an experienced urologist using the information in the urodynamic study (UDS) recordings. The compliance index defined on the basis of showed a significant difference (P<0.008) between the compliant and non-compliant groups. The areas under the receiver operating characteristic curve were 0.813, with 95% CI ranging from 0.709 to 0.892. Under the optimal criterion, the bladder was considered as non-compliant if the compliance index was less than 100 mL∙s/m, resulting in a sensitivity and specificity of 86.4% and 71.9%, respectively.

Conclusions: The results of this study demonstrate that UBV can be used as a non-invasive method for the determination of bladder compliance; thus, it can potentially serve as an alternative method to UDS for the appropriate patient groups.
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http://dx.doi.org/10.21037/atm-20-6900DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8105840PMC
April 2021

Final 5-Year Outcomes of the Multicenter Randomized Sham-Controlled Trial of a Water Vapor Thermal Therapy for Treatment of Moderate to Severe Lower Urinary Tract Symptoms Secondary to Benign Prostatic Hyperplasia.

J Urol 2021 Apr 19:101097JU0000000000001778. Epub 2021 Apr 19.

University of Texas Southwestern, Dallas, Texas.

Purpose: We present final 5-year outcomes of the multicenter randomized sham-controlled trial of a water vapor therapy (Rezūm™) for treatment of moderate to severe lower urinary tract symptoms due to benign prostatic hyperplasia.

Materials And Methods: A total of 197 subjects 50 years of age with International Prostate Symptom Score ≥13, maximum flow rate ≤15 ml/second and prostate volume 30 to 80 cc were randomized and followed for 5 years. From the control arm of 61 subjects, a subset of 53 subjects requalified and after 3 months received treatment as part of the crossover group and were also followed for 5 years. The total number of vapor treatments to each lobe of the prostate was determined by length of prostatic urethra and included middle lobe treatment per physician discretion.

Results: Significant improvement of lower urinary tract symptoms was observed at 3 months post-thermal therapy, remaining durable through 5 years in the treatment group (International Prostate Symptom Score reduced 48%, quality of life increased 45%, maximum flow rate improved 44%, Benign Prostatic Hyperplasia Impact Index decreased 48%). Surgical re-treatment rate was 4.4% with no reports of device or procedure related sexual dysfunction or sustained de novo erectile dysfunction. Results within the crossover group were similar through 5 years.

Conclusions: Minimally invasive treatment with water vapor thermal therapy provides significant and durable symptom relief as well as flow rate improvements through 5 years, with low surgical re-treatment rates and without impacting sexual function. It is a versatile therapy, providing successful treatment to obstructive lateral and middle lobes.
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http://dx.doi.org/10.1097/JU.0000000000001778DOI Listing
April 2021

Experimental Investigation of Cryoneedle Heating during MR-Guided Cryoablation in Ex Vivo Tissue Samples at 1.5-Tesla.

J Vasc Interv Radiol 2021 05 2;32(5):721-728.e2. Epub 2021 Mar 2.

Department of Radiology, Mayo Clinic, Rochester, Minnesota.

Purpose: To investigate cryoneedle heating risks during magnetic resonance (MR)-guided cryoablation and potential strategies to mitigate these risks.

Materials And Methods: Ex vivo experiments were performed on a 1.5-Tesla (T) MR scanner using an MR conditional cryoablation system on porcine tissue phantoms. Cryoneedles were placed inside the tissue phantom either with or without an angiocatheter. Typical cryoneedle geometric configurations (including gas supply line) encountered in clinical procedures with low to high expected heating risks were investigated. Up to 4 fiber optic temperature sensors were attached to the cryoneedle/angiocatheter to measure the MR-induced cryoneedle heating at different locations during MR with different estimated specific absorption rates (SARs). The impact of cryoneedle heating on cryoablation treatment was studied by comparing temperature changes during 10-min freeze-thaw cycles with and without MR.

Results: Rapid temperature increases of >100 °C in < 2 minutes were observed during MR with a SAR of 2.1 W/kg. The temperature changes during a typical freeze-thaw cycle were also affected by cryoneedle heating when MR was used to monitor the ice-ball evolution. The observed cryoneedle heating was affected by multiple factors; including cryoneedle geometric configurations, sequence SAR, whether an angiocatheter was used, and whether the cryoneedle was connected to the rest of the cryoablation system.

Conclusions: The ex vivo experiments demonstrated that MR could induce significant cryoneedle heating risks. Furthermore, MR-induced cryoneedle heating can affect temperatures in the ice-ball evolution during the freeze-thaw cycle. Several practical strategies to reduce the cryoneedle heating have been proposed.
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http://dx.doi.org/10.1016/j.jvir.2021.01.272DOI Listing
May 2021

Salvage ablation for locally recurrent prostate cancer.

Curr Opin Urol 2021 05;31(3):188-193

Department of Urology.

Purpose Of Review: This review aims to summarize the latest evidence for the use of salvage ablation of localized prostate cancer recurrences after primary therapy radiotherapy or prostatectomy.

Recent Findings: Savage ablation represents a treatment option in select patients with localized recurrences following primary therapy of prostate cancer. Following radiotherapy, salvage cryotherapy and high-intensity focused ultrasound (HIFU) demonstrate encouraging oncologic outcomes. Biochemical recurrence-free survival ranged from 71% at 2 years to 44.2% at 10 years for cryotherapy and from 51% at 5 years to 28.7% at 10 years for HIFU. Rates of adverse effects appear to be more favorable with ablation compared to salvage surgery. Focal salvage ablation may offer a further balance between oncologic control and adverse effects. Following radical prostatectomy, recent data on the use of salvage ablation of local recurrences are less robust with only a few small studies published in the last 2 years.

Summary: Salvage ablation is an option for localized disease recurrences following primary treatment. Its role is most established for postradiation recurrence. It can also be utilized in postprostatectomy recurrence, although published data is more limited. Future studies are needed to further explore the role of ablation in both cohorts.
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http://dx.doi.org/10.1097/MOU.0000000000000861DOI Listing
May 2021

Magnetic Resonance-Guided Prostate Ablation.

Semin Intervent Radiol 2019 Dec 2;36(5):351-366. Epub 2019 Dec 2.

Department of Urology, Mayo Clinic, Rochester, Minnesota.

In 2019, the American Cancer Society (ACS) estimates that 174,650 new cases of prostate cancer will be diagnosed and 31,620 will die due to the prostate cancer in the United States. Prostate cancer is often managed with aggressive curative intent standard therapies including radiotherapy or surgery. Regardless of how expertly done, these standard therapies often bring significant risk and morbidity to the patient's quality of life with potential impact on sexual, urinary, and bowel functions. Additionally, improved screening programs, using prostatic-specific antigen and transrectal ultrasound-guided systematic biopsy, have identified increasing numbers of low-risk, low-grade "localized" prostate cancer. The potential, localized, and indolent nature of many prostate cancers presents a difficult decision of when to intervene, especially within the context of the possible comorbidities of aggressive standard treatments. Active surveillance has been increasingly instituted to balance cancer control versus treatment side effects; however, many patients are not comfortable with this option. Although active debate continues on the suitability of either focal or regional therapy for the low- or intermediate-risk prostate cancer patients, no large consensus has been achieved on the adequate management approach. Some of the largest unresolved issues are prostate cancer multifocality, limitations of current biopsy strategies, suboptimal staging by accepted imaging modalities, less than robust prediction models for indolent prostate cancers, and safety and efficiency of the established curative therapies following focal therapy for prostate cancer. In spite of these restrictions, focal therapy continues to confront the current paradigm of therapy for low- and even intermediate-risk disease. It has been proposed that early detection and proper characterization may play a role in preventing the development of metastatic disease. There is level-1 evidence supporting detection and subsequent aggressive treatment of intermediate- and high-risk prostate cancer. Therefore, accurate assessment of cancer risk (i.e., grade and stage) using imaging and targeted biopsy is critical. Advances in prostate imaging with MRI and PET are changing the workup for these patients, and advances in MR-guided biopsy and therapy are propelling prostate treatment solutions forward faster than ever.
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http://dx.doi.org/10.1055/s-0039-1697001DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6887527PMC
December 2019

C-Choline PET Guided Salvage Radiation Therapy for Isolated Pelvic and Paraortic Nodal Recurrence of Prostate Cancer After Radical Prostatectomy: Rationale and Early Genitourinary or Gastrointestinal Toxicities.

Adv Radiat Oncol 2019 Oct-Dec;4(4):659-667. Epub 2019 Jul 4.

Department of Radiation Oncology, Rochester, Minnesota.

Purpose: To assess gastrointestinal (GI) and genitourinary (GU) adverse events (AEs) of C-choline-positron emission tomography (CholPET) guided lymph node (LN) radiation therapy (RT) in patients who experience biochemical failure after radical prostatectomy.

Methods And Materials: From 2013 to 2016, 107 patients experienced biochemical failure of prostate cancer, had CholPET-detected pelvic and/or paraortic LN recurrence, and were referred for RT. Patients received androgen suppression and CholPET guided LN RT (median dose, 45 Gy) with a simultaneous integrated boost to CholPET-avid sites (median dose, 56.25 Gy), all in 25 fractions. RT-naïve patients had the prostatic fossa included in the initial treatment volumes followed by a sequential boost (median dose, 68 Gy). GI and GU AEs were reported per Common Terminology Criteria for Adverse Events (version 4.0) with data gathered retrospectively. Differences in maximum GI and GU AEs at baseline, immediately post-RT, and at early (median, 4 months) and late (median, 14 months) follow-up were assessed.

Results: Median follow-up was 16 months (interquartile range [IQR], 11-25). Median prostate-specific antigen at time of positive CholPET was 2.3 ng/mL (IQR, 1.3-4.8), with a median of 2 (IQR, 1-4) choline-avid LNs per patient. Most recurrences were within the pelvis (53%) or pelvis + paraortic (40%). Baseline rates of grade 1 to 2 GI AEs were 8.4% compared with 51.9% (4.7% grade 2) of patients post-RT ( < .01). These differences resolved by 4-month (12.2%,  = .65) and 14-month AE assessments (9.1%,  = .87). There was no significant change in grade 1 to 2 GU AEs post-RT (64.1%) relative to baseline (56.0%,  = .21), although differences did arise at 4-month (72.2%,  = .01) and 14-month (74.3%,  = .01) AE assessments.

Conclusions: Salvage CholPET guided nodal RT has acceptably low rates of acute GI and GU AEs and no significant detriment in 14-month GI AEs. These data are of value in counseling patients and designing prospective trials evaluating the oncologic efficacy of this treatment strategy.
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http://dx.doi.org/10.1016/j.adro.2019.06.006DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6817538PMC
July 2019

Rectal wall saline displacement for improved margin during MRI-guided cryoablation of primary and recurrent prostate cancer.

Abdom Radiol (NY) 2020 04;45(4):1155-1161

Department of Urology, Mayo Clinic, Rochester, MN, USA.

Purpose: To describe safety, efficacy, and added oncologic margin of saline displacement of the rectal wall during MRI-guided cryoablation of primary and recurrent prostate cancer.

Methods: A retrospective review was conducted for patients who underwent MRI-guided cryoablation with saline displacement of the rectal wall for treatment of primary and recurrent prostate cancer over a 2-year period. Saline displacement was used when the distance from the edge of the ablation area to the rectal wall was insufficient to provide at least a 5-mm treatment margin. Pre- and post-ablation rectal wall displacement distances as well as ablative zone margins were assessed with MRI. Saline displacement distance was measured from the rectal wall to the edge of the lesion for focal lesion ablation and from the edge of the prostate for hemi-gland ablation. Immediate and intermediate-term complications were assessed.

Results: Saline displacement was used in 25 patients undergoing MRI-guided cryoablation. Twenty-one patients underwent salvage cryoablation, while four patients had it as primary treatment for prostate cancer. Median pre- and post- saline displacement rectal wall displacement distances were 6.0 and 11.2 mm, respectively (P < 0.0001). Median-added oncologic margin achieved by saline displacement was 4.6 mm (range 0.6-26.5). Median follow-up was 14 months (range 5-29). There were no intra-procedural complications and 3 patients experienced minor (Clavien-Dindo grade I) complications. One rectal complication occurred in a patient undergoing salvage cryotherapy with a history of extensive pelvic surgery and radiation.

Conclusions: Saline infusion at the time of MRI- guided cryoablation for prostate cancer resulted in increased distances between the target lesion and rectum. This is a useful technique in providing an added oncologic margin when treating lesions close to the rectal wall.
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http://dx.doi.org/10.1007/s00261-019-02147-4DOI Listing
April 2020

Current Status of MRI and PET in the NCCN Guidelines for Prostate Cancer.

J Natl Compr Canc Netw 2019 05;17(5):506-513

Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri.

Prostate cancer (PCa) represents a significant source of morbidity and mortality for men in the United States, with approximately 1 in 9 being diagnosed with PCa in their lifetime. The role of imaging in the evaluation of men with PCa has evolved and currently plays a central role in diagnosis, treatment planning, and evaluation of recurrence. Appropriate use of multiparametric MRI (mpMRI) and MRI-guided transrectal ultrasound (MR-TRUS) biopsy increases the detection of clinically significant PCa while decreasing the detection of clinically insignificant PCa. This process may help patients with clinically insignificant PCa avoid the adverse effects of unnecessary therapy. In the setting of a known PCa, patients with low-grade disease can be observed using active surveillance, which often includes a combination of prostate-specific antigen (PSA) testing, serial mpMRI, and, if indicated, follow-up systematic and targeted TRUS-guided tissue sampling. mpMRI can provide important information in the posttreatment setting, but PET/CT is creating a paradigm shift in imaging standards for patients with locally recurrent and metastatic PCa. This article examines the strengths and limitations of mpMRI for initial PCa diagnosis, active surveillance, recurrent disease evaluation, and image-guided biopsies, and the use of PET/CT imaging in men with recurrent PCa. The goal of this review is to provide a rational basis for current NCCN Clinical Practice Guidelines in Oncology for PCa as they pertain to the use of these advanced imaging modalities.
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http://dx.doi.org/10.6004/jnccn.2019.7306DOI Listing
May 2019

Evaluating the Potential Role of Salvage Vesiculectomy for Prostate Cancer Recurrence.

Clin Genitourin Cancer 2019 06 6;17(3):e536-e540. Epub 2019 Feb 6.

Department of Urology, Mayo Clinic, Rochester, MN. Electronic address:

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http://dx.doi.org/10.1016/j.clgc.2019.01.019DOI Listing
June 2019

Reducing seed migration to near zero with stranded-seed implants: Comparison of seed migration rates to the chest in 1000 permanent prostate brachytherapy patients undergoing implants with loose or stranded seeds.

Brachytherapy 2019 May - Jun;18(3):306-312. Epub 2019 Mar 8.

Department of Radiation Oncology, Mayo Clinic, Rochester, MN.

Purpose: Pulmonary seed emboli to the chest may occur after permanent prostate brachytherapy (PPB). The purpose of this study is to analyze factors associated with seed migration to the chest in a large series of PPB patients from a single institution undergoing implant with either loose seeds (LS), mixed loose and stranded seeds (MS), or exclusively stranded seeds in an absorbable vicryl suture (VS).

Methods And Materials: Between May 1998 and July 2015, a total of 1000 consecutive PPB patients with postoperative diagnostic chest x-rays at 4 months after implant were analyzed for seed migration. Patients were grouped based on seed implant technique: LS = 391 (39.1%), MS = 43 (4.3%), or VS = 566 (56.6%). Univariate and multivariate analysis were performed using Cox proportional hazards regression models to determine predictors of seed migration.

Results: Overall, 18.8% of patients experienced seed migration to the chest. The incidence of seed migration per patient was 45.5%, 11.6%, and 0.9% (p < 0.0001), for patients receiving LS, MS, or VS PPB, respectively. The right and left lower lobes were the most frequent sites of pulmonary seed migration. On multivariable analysis, planimetry volume (p = 0.0002; HR = 0.7 per 10 cc [0.6-0.8]), number of seeds implanted (p < 0.0001, HR = 2.4 per 25 seeds [1.7-3.4]), LS implant (p < 0.0001, HR = 15.9 [5.9-42.1]), and MS implant (p = 0.001, HR = 7.9 [2.3-28.1]) were associated with seed migration to the chest.

Conclusions: In this large series, significantly higher rates of seed migration to the chest are observed in implants using any LS with observed hazard ratios of 15.9 and 7.9 for LS and MS respectively, as compared with implants using solely stranded seeds.
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http://dx.doi.org/10.1016/j.brachy.2019.01.007DOI Listing
December 2019

Percutaneous Image-Guided Nodal Biopsy After 11C-Choline PET/CT for Biochemically Recurrent Prostate Cancer: Imaging Predictors of Disease and Clinical Implications.

Adv Radiat Oncol 2019 Jan-Mar;4(1):79-89. Epub 2018 Sep 5.

Department of Radiology, Mayo Clinic, Rochester, Minnesota.

Purpose: Management of recurrent prostate cancer necessitates timely diagnosis and accurate localization of the sites of recurrent disease. The purpose of this study was to assess predictors of histologic outcomes after 11C-choline positron emission tomography/computed tomography (CholPET) to increase the positive predictive value and specificity of CholPET in identifying imaging predictors of malignant and benign nodal disease to better inform clinical decision making regarding local therapy planning.

Materials And Methods: Retrospective review of patients undergoing CholPET followed by percutaneous core needle biopsy between January 1, 2010 and January 1, 2016. A total of 153 patients were identified who underwent 166 biopsy procedures. Patient, CholPET, procedural, and pathologic characteristics were recorded.

Results: A total of 157 biopsies were technically successful, and 110 (70.1%; 95% confidence interval, 62.2-77.1) yielded histologic results abnormal for metastatic prostate cancer. Lesion location, lesion maximum standardized uptake value (SUVmax), SUV ratio (calculated as the ratio of SUVmax to SUV mean in the right atrium), prostate-specific antigen, lesion short axis length, total Gleason score, and castration resistance were all associated with abnormal biopsy results ( values <.001, <.001, <.001, .02, .02, .02, and .015, respectively). External iliac, common iliac, and inguinal sites were associated with much lower rates of histologic positivity (mean [95% confidence interval], 51.2% [35.1-67.1], 46.2% [19.2-74.9], and 33.3% [7.5-70.1]), respectively.

Conclusions: In a cohort of patients in whom core needle biopsy was performed after CholPET, characteristics of choline localization including node location, SUVmax, lesion-to-blood pool SUV ratio, prostate-specific antigen, total Gleason score, and castration resistance were significantly associated with abnormal biopsy results for metastatic disease on CholPET. Relatively high false positive rates were found in common iliac, external iliac, and inguinal lymph node locations. Histologic confirmation of these sites should be strongly considered in the appropriate clinical scenario before designing additional local therapy plans.
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http://dx.doi.org/10.1016/j.adro.2018.08.022DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6349661PMC
September 2018

Targeted Prostate Biopsy and MR-Guided Therapy for Prostate Cancer.

Adv Exp Med Biol 2018;1096:159-184

Department of Urology, Mayo Clinic, Rochester, MN, USA.

In 2018, the American Cancer Society (ACS) estimates that 164,690 new cases of prostate cancer will be diagnosed and 29,430 will die due to the prostate cancer in the United States (Siegel et al., CA Cancer J Clin 67:7-30, 2018). Many men with prostate cancer are often managed with aggressive therapy including radiotherapy or surgery. No matter how expertly done, these therapies carry significant risk and morbidity to the patient's health related quality of life with impact on sexual, urinary and bowel function (Potosky et al., J Natl Cancer Inst 96:1358-1367, 2004). A recent meta-analysis of 19 studies reviewing the use of surgery and radiation for prostate cancer demonstrated patients who received radiation were more likely to die from their disease as compared to surgery (Wallis et al., Eur Urol 70:21-30, 2016). Furthermore, screening programs using prostatic specific antigen (PSA) and transrectal ultrasound (TRUS) guided systematic biopsy have identified increasing numbers of low risk, low grade "localized" prostate cancer. This indolent nature of many prostate cancers presents a difficult decision of when to intervene given the possible comorbidities of aggressive treatment. Active surveillance has been increasingly instituted in order to balance cancer control versus treatment side effects (Jemal et al., CA Cancer J Clin 56:106-130, 2006). Although active debate continues on the suitability of focal or regional therapy for these low or intermediate risk prostate cancer patients, many unresolved issues remain which complicate this approach of management. Some of the largest unresolved issues are: prostate cancer multifocality, limitations of current biopsy strategies, suboptimal staging by accepted imaging modalities, less than robust prediction models for indolent prostate cancers and whether established curative therapies can be safely and effectively used following focal therapy for prostate cancer. In spite of these restrictions focal therapy continues to confront the current paradigm of therapy for low and even intermediate risk disease (Onik, Tech Vasc Interv Radiol 10:149-158, 2017). It has been proposed that early detection and proper characterization may play a role in preventing the development of metastatic disease (Vickers et al., BMJ 346:f2023, 2013). There is Level 1 evidence supporting detection and subsequent aggressive treatment of intermediate and high-risk prostate cancer (Bill-Axelson et al., N Engl J Med 370:932-942, 2014). Therefore accurate assessment of cancer risk (i.e. grade and stage) using imaging and targeted biopsy is critical. Advances in prostate imaging with MRI have been accompanied with advances in MR guided therapy propelling prostate treatment solutions forward faster than ever.
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http://dx.doi.org/10.1007/978-3-319-99286-0_9DOI Listing
July 2019

Permanent prostate brachytherapy monotherapy with I-125 for low- and intermediate-risk prostate cancer: Outcomes in 974 patients.

Brachytherapy 2019 Jan - Feb;18(1):1-7. Epub 2018 Oct 4.

Department of Radiation Oncology, Mayo Clinic, Rochester, MN. Electronic address:

Purpose: To report outcomes of patients undergoing low-dose-rate (LDR) brachytherapy and investigate factors associated with biochemical failure and survival.

Methods: Consecutive patients undergoing LDR with I-125 at our institution between 1998 through 2013 for primary intact prostate cancer were examined. Those with low- and intermediate-risk disease receiving LDR with a minimum of 2 years followup and at least one post-LDR prostate-specific antigen (PSA) were included.

Results: About 974 patients satisfied inclusion criteria. With median followup of 72 months, biochemical failure occurred in 45 patients. Freedom from biochemical failure as defined by the Phoenix criterion was 96% and 88% at 5 and 10 years, worse for intermediate risk as compared with low risk, with 10-year freedom from biochemical failure of 76% versus 92% (hazard ratio [HR] = 3.7, p < 0.001), respectively. On multivariable analysis, increased prebiopsy PSA, Gleason 4 + 3, and no androgen deprivation therapy were associated with biochemical failure. Gleason 4 + 3 was the factor most strongly associated with biochemical failure (HR = 7.01, p < 0.001). No examined factors were associated with local failure. Gleason 4 + 3 disease increased the likelihood of distant metastasis (HR = 12.4, p = 0.003) and prostate cancer-specific death (HR = 13.2, p < 0.001). No difference in outcomes between patients with Gleason 3 + 3 versus 3 + 4 was observed.

Conclusions: LDR brachytherapy provided excellent outcomes in this large series of patients treated for localized organ-confined prostate cancer. Local recurrence at 10 years was low at 2.1%. Primary Gleason 4 + 3, higher pretreatment PSA, and no receipt of androgen deprivation therapy were the only factors associated with biochemical failure. Primary Gleason 4 disease was also predictive of distant metastases and decreased prostate cancer-specific survival.
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http://dx.doi.org/10.1016/j.brachy.2018.09.003DOI Listing
April 2019

Increased utilization of external beam radiotherapy relative to cystectomy for localized, muscle-invasive bladder cancer: a SEER analysis.

Bladder (San Franc) 2018 23;5(3):e34. Epub 2018 Aug 23.

Department of Radiation Oncology, Mayo Clinic, Rochester, MN, USA.

Objective: To assess recent utilization patterns of radiotherapy (RT) relative to cystectomy for muscle-invasive bladder cancer (MIBC) and evaluate survival trends over time in patients receiving RT.

Materials And Methods: The surveillance, epidemiology, and end results program (SEER) was used to identify patients diagnosed between 1992 and 2013 with localized MIBC. Patients with a prior history of non-bladder malignancy, who received no treatment, or did not have available treatment information, were excluded. Treatment utilization patterns were assessed using Cochran-Armitage tests for trend, and patient characteristics were compared using chi-square tests. Overall survival (OS) and cause-specific survival (CSS) were estimated using the Kaplan-Meier method. All-cause (ACM) and cause-specific mortality (CSM) were evaluated with multivariable Cox proportional hazards regression.

Results: Of 16175 patients analyzed, 11917 (74%) underwent cystectomy, and 4258 (26%) were treated with RT. Patients who received RT were older (median age 79 . 68, < 0.01). Over time, the proportion of patients receiving RT relative to cystectomy increased (24% 1992-2002 . 28% 2003-2013, < 0.01), despite median patient age throughout the study period remaining unchanged (71 for each 1992-2002 and 2003-2013, = 0.41). For RT, compared with patients diagnosed earlier, those diagnosed from 2010-2013 showed improved OS (64% . 60% at 1 year, < 0.01; 38% . 29% at 3 years, < 0.01) and CSS (71% . 67% at 1 year, = 0.01; 51% . 40% at 3 years, < 0.01). On multivariable analysis, diagnosis from 2010-2013 was associated with a lower estimated risk of ACM (hazard ratio 0.77; 95% confidence interval 0.66-0.89, < 0.001) and CSM (hazard ratio 0.81; 95% confidence interval 0.67-0.97, = 0.02).

Conclusion: Utilization of RT for localized MIBC increased relative to cystectomy from 1992 to 2013, despite the median age of treated patients remaining unchanged. More recent survival outcomes for patients receiving RT were improved, supporting continued use of bladder preservation strategies utilizing RT.
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http://dx.doi.org/10.14440/bladder.2018.639DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7401988PMC
August 2018

Low dose rate prostate brachytherapy.

Transl Androl Urol 2018 Jun;7(3):341-356

Department of Radiation Oncology, Mayo Clinic, Rochester, MN 55905, USA.

Low dose rate (LDR) prostate brachytherapy is an evidence based radiation technique with excellent oncologic outcomes. By utilizing direct image guidance for radioactive source placement, LDR brachytherapy provides superior radiation dose escalation and conformality compared to external beam radiation therapy (EBRT). With this level of precision, late grade 3 or 4 genitourinary or gastrointestinal toxicity rates are typically between 1% and 4%. Furthermore, when performed as a same day surgical procedure, this technique provides a cost effective and convenient strategy. A large body of literature with robust follow-up has led multiple expert consensus groups to endorse the use of LDR brachytherapy as an appropriate management option for all risk groups of non-metastatic prostate cancer. LDR brachytherapy is often effective when delivered as a monotherapy, although for some patients with intermediate or high-risk disease, optimal outcome are achieved in combination with supplemental EBRT and/or androgen deprivation therapy (ADT). In addition to reviewing technical aspects and reported clinical outcomes of LDR prostate brachytherapy, this article will focus on the considerations related to appropriate patient selection and other aspects of its use in the treatment of prostate cancer.
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http://dx.doi.org/10.21037/tau.2017.12.15DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6043740PMC
June 2018

MR-Guided Prostate Interventions.

Top Magn Reson Imaging 2018 Jun;27(3):141-151

Mayo Clinic, Department of Urology, Rochester, MN.

Prostate cancer is the most commonly diagnosed noncutaneous cancer and second leading cause of death in men. Many patients with clinically organ-confined prostate cancer undergo definitive treatment of the whole gland, including radical prostatectomy, radiation therapy, and cryosurgery. Active surveillance is a growing alternative option for patients with documented low-volume and low-grade prostate cancer. However, many patients are wanting a less morbid focal treatment alternative. With recent advances in software and hardware of magnetic resonance imaging (MRI), multiparametric MRI of the prostate has been shown to improve the accuracy in detecting and characterizing clinically significant prostate cancer. Targeted biopsy is increasingly utilized to improve the yield of MR detected, clinically significant prostate cancer and to decrease in detection of indolent prostate cancer. MR-guided targeted biopsy techniques include cognitive MR fusion transrectal ultrasound (TRUS) biopsy, in-bore transrectal targeted biopsy using robotic transrectal device, and in-bore direct MR-guided transperineal biopsy with a software based transperineal grid template. In addition, advances in MR-compatible thermal ablation technology allow accurate focal or regional delivery of thermal ablative energy to the biopsy-proved, MRI-detected tumor. MR-guided ablative treatment options include cryoablation, laser ablation, and high-intensity focused ultrasound with real-time or near simultaneous monitoring of the ablation zone. We present a contemporary review of MR-guided techniques for prostatic interventions.
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http://dx.doi.org/10.1097/RMR.0000000000000155DOI Listing
June 2018

MRI-Targeted or Standard Biopsy for Prostate-Cancer Diagnosis.

N Engl J Med 2018 May 18;378(19):1767-1777. Epub 2018 Mar 18.

From University College London (UCL) and UCL Hospitals NHS Foundation Trust (V.K., C.A., F.G., A.F., S.M., S.P., M.E., C.M.M.), London North West Healthcare NHS Trust (G.H.), Whittington Health NHS Trust (M.G.), Royal Free London NHS Foundation Trust (P.B.S.), and UCL Surgical and Interventional Trials Unit (N.R.W., C.B.-G.), London, Hampshire Hospitals NHS Foundation Trust, Basingstoke (R.G.H.), Princess Alexandra Hospital NHS Trust, Harlow (J.V.), and the Institute of Applied Health Research and the NIHR Birmingham Biomedical Research Centre, University of Birmingham, Birmingham (J.D., Y.T.) - all in the United Kingdom; Helsinki University and Helsinki University Hospital, Helsinki (A.S.R.), and Medical Research Center Oulu, University of Oulu and Oulu University Hospital, Oulu (M.H.V.) - all in Finland; Centro de Urología, Buenos Aires (M.B.); Sapienza University, Rome (V.P.), and IRCCS Ospedale San Raffaele and Vita-Salute San Raffaele University, Milan (A.B.) - all in Italy; Mayo Clinic, Rochester, MN (L.A.M.); Martini Klinik, Hamburg (L.B.), University Hospital Essen, Essen (B.A.H.), and University Hospital Heidelberg, Heidelberg (B.A.H.) - all in Germany; Erasmus University Medical Center, Rotterdam (M.J.R.), and Radboud University Medical Center, Nijmegen (W.V.) - both in the Netherlands; University of Chicago, Chicago (S.E.); Université de Lille and Centre Hospitalier Universitaire Lille, Lille (A.V.), Université de Bordeaux and Bordeaux Pellegrin University Hospital, Bordeaux (G.R.), and Hospices Civils de Lyon, Centre Hospitalier Lyon-Sud (A.R.), and Hospices Civils de Lyon of the Hôpital Edouard Herriot (S.C.), Lyon - all in France; Jewish General Hospital, Montreal (F.B.), and Sunnybrook Health Sciences Centre, Toronto (L.K.) - both in Canada; Ghent University Hospital, Ghent, Belgium (G.M.V.); University Hospital Bern, Bern, Switzerland (S.B.); Weill Cornell Medicine, New York-Presbyterian Hospital (J.C.H., D.M.), and New York University Langone Medical Center (S.S.T.), New York; National Institutes of Health, Bethesda, MD (P.P.); and the University of Southern California Institute of Urology, Keck School of Medicine, Los Angeles (I.G.).

Background: Multiparametric magnetic resonance imaging (MRI), with or without targeted biopsy, is an alternative to standard transrectal ultrasonography-guided biopsy for prostate-cancer detection in men with a raised prostate-specific antigen level who have not undergone biopsy. However, comparative evidence is limited.

Methods: In a multicenter, randomized, noninferiority trial, we assigned men with a clinical suspicion of prostate cancer who had not undergone biopsy previously to undergo MRI, with or without targeted biopsy, or standard transrectal ultrasonography-guided biopsy. Men in the MRI-targeted biopsy group underwent a targeted biopsy (without standard biopsy cores) if the MRI was suggestive of prostate cancer; men whose MRI results were not suggestive of prostate cancer were not offered biopsy. Standard biopsy was a 10-to-12-core, transrectal ultrasonography-guided biopsy. The primary outcome was the proportion of men who received a diagnosis of clinically significant cancer. Secondary outcomes included the proportion of men who received a diagnosis of clinically insignificant cancer.

Results: A total of 500 men underwent randomization. In the MRI-targeted biopsy group, 71 of 252 men (28%) had MRI results that were not suggestive of prostate cancer, so they did not undergo biopsy. Clinically significant cancer was detected in 95 men (38%) in the MRI-targeted biopsy group, as compared with 64 of 248 (26%) in the standard-biopsy group (adjusted difference, 12 percentage points; 95% confidence interval [CI], 4 to 20; P=0.005). MRI, with or without targeted biopsy, was noninferior to standard biopsy, and the 95% confidence interval indicated the superiority of this strategy over standard biopsy. Fewer men in the MRI-targeted biopsy group than in the standard-biopsy group received a diagnosis of clinically insignificant cancer (adjusted difference, -13 percentage points; 95% CI, -19 to -7; P<0.001).

Conclusions: The use of risk assessment with MRI before biopsy and MRI-targeted biopsy was superior to standard transrectal ultrasonography-guided biopsy in men at clinical risk for prostate cancer who had not undergone biopsy previously. (Funded by the National Institute for Health Research and the European Association of Urology Research Foundation; PRECISION ClinicalTrials.gov number, NCT02380027 .).
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http://dx.doi.org/10.1056/NEJMoa1801993DOI Listing
May 2018

Robust and efficient pharmacokinetic parameter non-linear least squares estimation for dynamic contrast enhanced MRI of the prostate.

Magn Reson Imaging 2018 05 24;48:50-61. Epub 2017 Dec 24.

Biomedical Engineering and Physiology Program, Mayo Graduate School, Rochester, MN, United States; Department of Radiology, Mayo Clinic, Rochester, MN, United States. Electronic address:

Purpose: To describe an efficient numerical optimization technique using non-linear least squares to estimate perfusion parameters for the Tofts and extended Tofts models from dynamic contrast enhanced (DCE) MRI data and apply the technique to prostate cancer.

Methods: Parameters were estimated by fitting the two Tofts-based perfusion models to the acquired data via non-linear least squares. We apply Variable Projection (VP) to convert the fitting problem from a multi-dimensional to a one-dimensional line search to improve computational efficiency and robustness. Using simulation and DCE-MRI studies in twenty patients with suspected prostate cancer, the VP-based solver was compared against the traditional Levenberg-Marquardt (LM) strategy for accuracy, noise amplification, robustness to converge, and computation time.

Results: The simulation demonstrated that VP and LM were both accurate in that the medians closely matched assumed values across typical signal to noise ratio (SNR) levels for both Tofts models. VP and LM showed similar noise sensitivity. Studies using the patient data showed that the VP method reliably converged and matched results from LM with approximate 3× and 2× reductions in computation time for the standard (two-parameter) and extended (three-parameter) Tofts models. While LM failed to converge in 14% of the patient data, VP converged in the ideal 100%.

Conclusion: The VP-based method for non-linear least squares estimation of perfusion parameters for prostate MRI is equivalent in accuracy and robustness to noise, while being more reliably (100%) convergent and computationally about 3× (TM) and 2× (ETM) faster than the LM-based method.
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http://dx.doi.org/10.1016/j.mri.2017.12.021DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5889971PMC
May 2018

Multiparametric Magnetic Resonance Imaging Is an Independent Predictor of Salvage Radiotherapy Outcomes After Radical Prostatectomy.

Eur Urol 2018 06 28;73(6):879-887. Epub 2017 Nov 28.

Department of Urology, Mayo Clinic, Rochester, MN, USA. Electronic address:

Background: The Stephenson nomogram is widely used to estimate the success of salvage radiotherapy (sXRT) for prostate cancer (PCa) recurrence after radical prostatectomy (RP).

Objective: To determine whether multiparametric pelvic magnetic resonance imaging (mpMRI) performed for biochemical recurrence after RP improves prognostication of sXRT relative to the Stephenson nomogram.

Design, Setting, And Participants: Men undergoing RP at our institution from 2003 to 2012 who had biochemical recurrence evaluated by mpMRI within 12 mo of sXRT were retrospectively reviewed. Exclusion criteria included PCa treatment prior to RP, adjuvant XRT after RP, salvage cryotherapy before sXRT, and hormone refractory disease prior to sXRT.

Outcome Measurements And Statistical Analysis: Multivariable Cox regression analyses (adjusting for Stephenson nomogram covariates) associated mpMRI findings with prostate-specific antigen (PSA) recurrence and metastasis after sXRT. The mpMR images were compared in a binary fashion: no lesion versus vesicourethral/seminal vesical bed/prostate fossa lesions.

Results And Limitations: Among 473 sXRT patients, 57%(204) had lesions on mpMRI: 26%(124) vesicourethral, 28%(135) seminal vesical bed/prostatic fossa, 7%(34) nodal, and 1%(3) bone. Median PSA at mpMRI with lesions was 0.46 versus 0.40ng/ml without lesions. After excluding nodal/bone lesions, 29% of men developed PSA recurrence and 14% metastasis (median follow-up 45 mo after sXRT). For patients with a pre-sXRT PSA of ≤0.5ng/ml, negative mpMRI was associated with increased PSA recurrence (39% vs 12%, p<0.01) and metastasis (16% vs 2%, p<0.01) at 4 yr after sXRT. For patients with a PSA of ≤0.5ng/ml, the addition of mpMRI to the propensity score (created using variables from the original Stephenson nomogram) improved the c-statistic from 0.71 to 0.77 for PSA recurrence (hazard ratio [HR] 3.60, p<0.01) and from 0.66 to 0.77 for metastasis (HR 6.68, p<0.01). Limitations include evolutions in MRI technique and lack of a cohort of men undergoing mpMRI electing against sXRT.

Conclusions: Pre-sXRT mpMRI improves clinicopathologic variables to estimate sXRT success, particularly in the early sXRT setting.

Patient Summary: Men who have biochemically recurrent prostate cancer after radical prostatectomy often receive salvage radiotherapy. In our study, multiparametric pelvic magnetic resonance imaging prior to salvage radiotherapy was a significant predictor of prostate-specific antigen failure and metastasis after radiotherapy.
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http://dx.doi.org/10.1016/j.eururo.2017.11.012DOI Listing
June 2018

Whole-Gland Prostate Cancer Cryoablation with Magnetic Resonance Imaging Guidance: One-Year Follow-Up.

Cardiovasc Intervent Radiol 2018 Feb 17;41(2):344-349. Epub 2017 Oct 17.

Interventional Radiology Department, Mayo Clinic, Rochester, MN, USA.

Purpose: Patients who develop prostate cancer after prior abdominal perineal resection are poor surgical candidates, and have limited treatment options. Therefore, our goal is to present results from a single institutional experience of four patients who underwent whole gland MRI-guided cryoablation with a history complicated by prior abdominoperineal resection.

Materials And Methods: Four MRI-guided cryoablative treatments (mean age 64, range 59-69 years) for primary and locally recurrent prostate adenocarcinoma were retrospectively reviewed in patients with prior abdominal perineal resection for colorectal cancer (3) and juvenile polyposis (1). Average prostate volume prior to ablation was 23 cc, with an average PSA of 5.6 ng/mL. For each gland, 7-10 cryoprobes were placed approximately 0.5 cm apart in the prostate gland under MRI guidance by a transperineal approach with 3-4 freeze-thaw cycles performed. Each patient had follow up imaging and PSA measurements out to 12 months post ablation.

Results: All four patient's PSA dropped below 0.1 ng/mL at 3-6 month post-ablation and remained at these levels at 12 months. Three of the 4 patients had PSA measurements to 33 months post-ablation, with no evidence of recurrence. No patient developed urinary incontinence due to the whole gland cryoablation.

Conclusion: With all four patients in our study having undetectable PSAs 12 months post ablation, and with no patient developing urinary incontinence due to the cryoablation, MRI-guided cryoablation appears to be a promising treatment option in patients who are poor surgical candidates due to prior pelvic surgery and/or radiation.
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http://dx.doi.org/10.1007/s00270-017-1799-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5783320PMC
February 2018

Identification of Recurrence Sites Following Post-Prostatectomy Treatment for Prostate Cancer Using C-Choline Positron Emission Tomography and Multiparametric Pelvic Magnetic Resonance Imaging.

J Urol 2018 03 12;199(3):726-733. Epub 2017 Sep 12.

Department of Urology, Mayo Clinic, Rochester, Minnesota. Electronic address:

Purpose: We describe anatomical sites of recurrence in patients with prostate cancer who had biochemical recurrence following radical prostatectomy and who received radiotherapy and/or androgen deprivation therapy postoperatively. We performed C-choline positron emission tomography/computerized tomography and multiparametric magnetic resonance imaging.

Materials And Methods: After radiotherapy and/or androgen deprivation therapy patients who underwent radical prostatectomy were evaluated by C-choline positron emission tomography/computerized tomography and multiparametric magnetic resonance imaging to determine recurrence patterns and clinicopathological features. Recurrent sites were described as local only (seminal vesicle bed/prostate fossa, vesicourethral anastomosis and bladder neck) or distant metastatic disease. Features associated with the identification of any distant metastatic disease were evaluated by multivariable logistic regression.

Results: A total of 550 patients were identified. Treatment included androgen deprivation therapy in 108, radiotherapy in 201, and androgen deprivation therapy and radiotherapy in 241. Median prostate specific antigen at evaluation was 3.9, 3.6 and 2.8 ng/ml in patients treated with androgen deprivation therapy, radiotherapy and a combination, respectively. Recurrence developed locally in 77 patients (14%), as distant metastasis only in 411 (75%), and as local and distant metastatic disease in 62 (11%). On multivariable analysis treatment with radiotherapy (OR 7.18, 95% CI 2.92-17.65), and radiotherapy and hormonal therapy (OR 9.23, 95% CI 3.90-21.87, all p <0.01) was associated with increased odds of distant failure at evaluation.

Conclusions: The combination of C-choline positron emission tomography/computerized tomography and multiparametric magnetic resonance imaging successfully identified patterns of recurrence after postoperative radiotherapy and/or androgen deprivation therapy at a median prostate specific antigen of less than 4 ng/ml. Half of this cohort had local only recurrence and/or a low disease burden limited to pelvic lymph nodes. These patients may benefit from additional local therapy. These data and this analysis may facilitate the evaluation of such patients with biochemically recurrent prostate cancer.
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http://dx.doi.org/10.1016/j.juro.2017.09.033DOI Listing
March 2018

Brachytherapy in the Management of Prostate Cancer.

Surg Oncol Clin N Am 2017 07 11;26(3):491-513. Epub 2017 May 11.

Department of Radiation Oncology, Mayo Clinic, 200 First Street Southwest, Rochester, MN 55905, USA.

Brachytherapy is performed by directly inserting radioactive sources into the prostate gland and is an important treatment option for appropriately selected men with prostate adenocarcinoma. Brachytherapy provides highly conformal radiotherapy and delivers tumoricidal doses that exceed those administered with external beam radiation therapy. There is a significant body of literature supporting the excellent long-term oncologic and safety outcomes achieved when brachytherapy is used for men in all risk categories of nonmetastatic prostate cancer. This article highlights some important considerations and published outcomes that relate to brachytherapy and its role in the treatment of prostate cancer.
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http://dx.doi.org/10.1016/j.soc.2017.01.008DOI Listing
July 2017

Improved performance of prostate DCE-MRI using a 32-coil vs. 12-coil receiver array.

Magn Reson Imaging 2017 06 27;39:15-23. Epub 2017 Jan 27.

Department of Radiology, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, United States. Electronic address:

Purpose: To assess whether acquisition with 32 receiver coils rather than the vendor-recommended 12 coils provides significantly improved performance in 3D dynamic contrast-enhanced MRI (DCE-MRI) of the prostate.

Materials: The study was approved by the institutional review board and was compliant with HIPAA. 50 consecutive male patients in whom prostate MRI was clinically indicated were prospectively imaged in March 2015 with an accelerated DCE-MRI sequence in which image reconstruction was performed using 12 and 32 coil elements. The two reconstructions were compared quantitatively and qualitatively. The first was done using signal-to-noise ratio (SNR) and g-factor analysis to assess sensitivity to acceleration. The second was done using a five-point scale by two experienced radiologists using criteria of perceived SNR, artifact, sharpness, and overall preference. Significance was assessed with the Wilcoxon signed rank test. Extension to T2-weighted spin-echo and diffusion sequences was assessed in phantom studies.

Results: Reconstruction using 32 vs. 12 coil elements provided improved performance in DCE-MRI based on intrinsic SNR (18% higher) and g-factor statistics (14% higher), with a median 32% higher overall SNR within the prostate volume over all subjects. Reconstruction using 32 coils was qualitatively rated significantly improved (p<0.001) vs. 12 coils on the basis of perceived SNR and radiologist preference and equivalent for sharpness and artifact. Phantom studies suggested the improvement in intrinsic SNR could extend to T2-weighted spin-echo and diffusion sequences.

Conclusions: Reconstruction of 3D accelerated DCE-MRI studies of the prostate using 32 independent receiver coils provides improved overall performance vs. using 12 coils.
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http://dx.doi.org/10.1016/j.mri.2017.01.017DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5410393PMC
June 2017

Patterns of Recurrence After Postprostatectomy Fossa Radiation Therapy Identified by C-11 Choline Positron Emission Tomography/Computed Tomography.

Int J Radiat Oncol Biol Phys 2017 03 17;97(3):526-535. Epub 2016 Nov 17.

Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota. Electronic address:

Purpose: To evaluate C-11 choline positron emission tomography/computed tomography (CholPET) in staging and determining patterns of recurrence in prostate cancer patients with rising prostate-specific antigen levels after prostatectomy radiation therapy (RT).

Methods And Materials: The study includes patients with biochemical failure after postprostatectomy RT who underwent CholPET between 2008 and 2015. Patient and disease characteristics were examined in relation to sites of recurrence. All RT dosimetry records were reviewed, and recurrences were mapped on a representative computed tomography dataset with their relationship relative to the irradiated fossa field as out of field (OOF), edge of field (EOF; recurrence within <45-Gy isodose lines), or in field (IF; recurrence within ≥45-Gy isodose lines).

Results: Forty-one patients were identified with 121 sites of recurrence (median 2 sites; interquartile range [IQR], 1-4). The median prostate-specific antigen level at CholPET was 3.1 (IQR, 1.9-5.6) ng/mL. Median interval from RT to biochemical failure was 24 (IQR, 10-46) months, with recurrence identified on CholPET at a median of 15 (IQR, 7-28) months from biochemical failure. Histologic confirmation of recurrence was obtained in 20 patients (49%), with the remainder confirmed by treatment response. Five patients (12%) had IF recurrences, 10 patients (24%) had EOF recurrences (median dose 10 Gy; IQR, 5-30 Gy), and 36 patients (88%) had OOF recurrences. Ten patients had combination failures: 6 (15%) EOF/OOF and 4 (10%) IF/OOF. Fifty-seven recurrences (47%) were pelvic nodal sites inferior to the L5-S1 interspace, of which 52 (43%) were within a pelvic RT field. Eighty-one recurrences (67%) were nodal and inferior to the aortic bifurcation.

Conclusions: Using CholPET, we found that the majority of patients evaluated for biochemical failure recurred outside of the postprostatectomy RT field. Furthermore, most recurrence sites were nodal and inferior to the aortic bifurcation. These results provide data that may be useful for examining strategies that include elective lymph node irradiation in postprostatectomy patients.
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http://dx.doi.org/10.1016/j.ijrobp.2016.11.014DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5308881PMC
March 2017

Convective Thermal Therapy: Durable 2-Year Results of Randomized Controlled and Prospective Crossover Studies for Treatment of Lower Urinary Tract Symptoms Due to Benign Prostatic Hyperplasia.

J Urol 2017 06 18;197(6):1507-1516. Epub 2016 Dec 18.

Department of Urology, University of Texas Southwestern Medical Center (CGR), Dallas, Texas.

Purpose: We report 2-year outcomes of a multicenter randomized controlled trial plus 1-year results of a crossover trial after treatment with convective radiofrequency water vapor thermal energy for lower urinary tract symptoms due to benign prostatic hyperplasia.

Materials And Methods: A total of 197 men at least 50 years old with I-PSS (International Prostate Symptom Score) 13 or greater, maximum flow rate 15 ml per second or less and prostate size 30 to 80 cc were randomized 2:1 to thermal therapy with the Rezūm® System or a control group. Rigid cystoscopy with simulated active treatment sounds served as the control procedure. After unblinding at 3 months control subjects could requalify for crossover study. Convectively delivered radiofrequency thermal energy was delivered into obstructive prostate tissue, including the median lobe as needed. The primary efficacy end point was a change in severity of symptom scores.

Results: Convective radiofrequency thermal therapy improved urinary symptoms significantly over controls at 3 months and provided a sustained 51% reduction from baseline at 24 months (p <0.0001). This produced a 5 and 8-point or greater score decrease in 84% and 74% of subjects, respectively, at 24 months. Crossover subject symptoms, flow rate and quality of life measures were markedly improved after thermal therapy compared to after the control procedure (p = 0.024 to <0.0001). No de novo erectile dysfunction was reported.

Conclusions: Convective radiofrequency water vapor thermal therapy is a minimally invasive office or outpatient procedure that provides early effective symptom relief that remains durable for 2 years and is applicable to the median lobe.
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http://dx.doi.org/10.1016/j.juro.2016.12.045DOI Listing
June 2017

CT-guided transgluteal biopsy for systematic sampling of the prostate in patients without rectal access: a 13-year single-center experience.

Eur Radiol 2017 Aug 14;27(8):3326-3332. Epub 2016 Dec 14.

Department of Radiology, Mayo Clinic, 200 1st St SW, Rochester, MN, 55905, USA.

Objectives: The purpose of our study was to examine the safety and diagnostic utility of transgluteal CT-guided prostate biopsy for prostate sampling in patients without rectal access.

Methods: Seventy-three biopsies were performed in 65 patients over a 13-year period (2002-2015). Mean prostate-specific antigen (PSA) at biopsy was 7.8 ng/mL (range 0.37-31.5). Electronic medical records were reviewed for procedural details and complications. Mean PSA and number of cores in malignant and benign cohorts were compared with Student's t test.

Results: Technical success rate was 97.3% (71/73; mean cores 8, range 3-28). Of these, 43.6% (31/71) yielded malignancy (mean Gleason score 7, range 6-10) and 56.3% (40/71) yielded benign tissue. The only complication was an asymptomatic periprostatic hematoma (1/73; 1.4%). In 14 patients who underwent surgery, Gleason scores were concordant in 71.4% (10/14) and discordant in 28.6% (4/14; Gleason 6 on biopsy but Gleason 7 on surgical specimen). Mean effective radiation dose was 18.5 mSv (median 15.0, range 4.4-86.2). There was no significant difference in either mean PSA (p = 0.06) or number of core specimens (p = 0.33) between malignant and benign cohorts.

Conclusion: CT-guided transgluteal prostate biopsy is highly safe and reliable for the detection of prostate cancer in men without rectal access.

Key Points: • Prostate cancer detection in men without rectal access is challenging. • CT-guided transgluteal prostate biopsy is safe and effective in these patients. • CT-guided biopsy may be particularly effective in diagnosing high-grade prostate cancer. • Unilateral CT-guided biopsy may be effective in patients with focal lesions. • The radiation exposure with this technique is acceptable.
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http://dx.doi.org/10.1007/s00330-016-4694-7DOI Listing
August 2017

Two-year results after convective radiofrequency water vapor thermal therapy of symptomatic benign prostatic hyperplasia.

Res Rep Urol 2016 21;8:207-216. Epub 2016 Nov 21.

Department of Urology, Mayo Clinic, Rochester, MN, USA.

Objective: The objective of this study was to assess the effectiveness and safety of convective radiofrequency (RF) water vapor thermal therapy in men with lower urinary tract symptoms (LUTS) associated with benign prostatic hyperplasia (BPH); a pilot study design with 2-year follow-up evaluations.

Patients And Methods: Men aged ≥45 years with an International Prostate Symptom Score ≥13, a maximum urinary flow rate (Q) ≤15 mL/s, and prostate volume 20-120 cc were enrolled in a prospective, open-label pilot study using convective RF water vapor energy with the Rezūm System. Patients were followed up for 2 years after transurethral thermal treatment at 3 international centers in the Dominican Republic, Czech Republic, and Sweden. The transurethral thermal therapy utilizes radiofrequency to generate wet thermal energy in the form of water vapor injected through a rigid endoscope into the lateral lobes and median lobe as needed. Urinary symptom relief, urinary flow, quality of life (QOL) impact, sexual function, and adverse events (AEs) were assessed at 1 week, 1, 3, 6, 12, and 24 months.

Results: LUTS, flow rate, and QOL showed significant improvements from baseline; prostate volumes were appreciably reduced. Sexual function was maintained and no erectile dysfunction occurred. The responses evident as early as 1 month after treatment remained consistent and durable over the 24 months of study. Early AEs were typically transient and mild to moderate; most were related to endoscopic instrumentation. No procedure related to late AEs were seen.

Conclusion: The Rezūm System convective RF thermal therapy is a minimally invasive treatment for BPH/LUTS which can be performed in the office or as an outpatient procedure with minimal associated perioperative AEs. It has no discernable effect on sexual function and provides significant improvement of LUTS that remain durable at 2 years.
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http://dx.doi.org/10.2147/RRU.S119596DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5123707PMC
November 2016
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