Publications by authors named "Venkatesh Rangarajan"

194 Publications

Emerging role of artificial intelligence in nuclear medicine.

Nucl Med Commun 2021 Mar 1. Epub 2021 Mar 1.

Department of Radiation Oncology (Maastro), GROW School for Oncology, Maastricht University Medical Centre, Maastricht, The Netherlands Department of Nuclear Medicine and Molecular Imaging, Tata Memorial Hospital Homi Bhabha National Institute (HBNI), Deemed University, Mumbai, India.

The role of artificial intelligence is increasing in all branches of medicine. The emerging role of artificial intelligence applications in nuclear medicine is going to improve the nuclear medicine clinical workflow in the coming years. Initial research outcomes are suggestive of increasing role of artificial intelligence in nuclear medicine workflow, particularly where selective automation tasks are of concern. Artificial intelligence-assisted planning, dosimetry and procedure execution appear to be areas for rapid and significant development. The role of artificial intelligence in more directly imaging-related tasks, such as dose optimization, image corrections and image reconstruction, have been particularly strong points of artificial intelligence research in nuclear medicine. Natural Language Processing (NLP)-based text processing task is another area of interest of artificial intelligence implementation in nuclear medicine.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/MNM.0000000000001381DOI Listing
March 2021

Improving accuracy of 18F-fluorodeoxyglucose PET computed tomography to diagnose nodal involvement in non-small cell lung cancer: utility of using various predictive models.

Nucl Med Commun 2021 Feb 5. Epub 2021 Feb 5.

Department of Nuclear Medicine and Molecular Imaging, Tata Memorial Hospital, Homi Bhabha National Institute Thoracic Surgery, Department of Surgical Oncology, Tata Memorial Hospital, Homi Bhabha National Institute Departments of Pathology Radiation Oncology Medical Oncology Chest Medicine, Tata Memorial Hospital, Homi Bhabha National Institute, Mumbai, India.

Purpose: To determine predictive models (PM) that could improve the accuracy for identifying metastatic regional nodes in non-small cell lung cancer based on both PET and CT findings seen on 18F-FDG PET CT.

Methods: Three hundred thirty-nine biopsy-proven NSCLC patients who underwent surgical resection and had a staging 18F-FDG PET CT were enrolled. PET parameters obtained were (1) presence of visual PET positive nodes, (2) SUVmax of nodes (NSUV), (3) ratio of node to aorta SUVmax (N/A ratio) and (4) ratio of node to primary tumour SUVmax (N/T ratio). CT parameters obtained were (1) short-axis diameter and (2) Hounsfield units (HU) of PET-positive nodes. PET and CT parameters were correlated with nodal histopathology to find out the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and overall accuracy. Different PM combining these parameters were devised and the incremental improvement in accuracy was determined.

Results: Visual PET positivity showed sensitivity, specificity, PPV, NPV and accuracy of 72.4, 76.1, 30.1, 95.1 and 75.6, respectively. PM2 which combined visual PET positivity, NSUV and HU appears more clinically relevant and showed sensitivity, specificity, PPV, NPV and accuracy of 53.5, 96.5, 68.9, 93.6 and 91.2, respectively. PM6 which combined visual PET positivity, NSUV, N/A ratio and HU showed the maximum PPV (80.0%), specificity (98.3%) and accuracy of (91.9%).

Conclusion: PM combining parameters like nodal SUVmax, N/A ratio, N/T ratio and HU values have shown to improve the PPV, specificity and overall accuracy of 18FDG PET CT in the preoperative diagnosis of nodal metastases.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/MNM.0000000000001367DOI Listing
February 2021

Prostate-Only Versus Whole-Pelvic Radiation Therapy in High-Risk and Very High-Risk Prostate Cancer (POP-RT): Outcomes From Phase III Randomized Controlled Trial.

J Clin Oncol 2021 Jan 26:JCO2003282. Epub 2021 Jan 26.

Department of Radiation Oncology, Tata Memorial Hospital and Advanced Centre for Treatment Research and Education in Cancer (ACTREC), Homi Bhabha National Institute (HBNI), Mumbai, India.

Purpose: We report the clinical outcomes of a randomized trial comparing prophylactic whole-pelvic nodal radiotherapy to prostate-only radiotherapy (PORT) in high-risk prostate cancer.

Methods: This phase III, single center, randomized controlled trial enrolled eligible patients undergoing radical radiotherapy for node-negative prostate adenocarcinoma, with estimated nodal risk ≥ 20%. Randomization was 1:1 to PORT (68 Gy/25# to prostate) or whole-pelvic radiotherapy (WPRT, 68 Gy/25# to prostate, 50 Gy/25# to pelvic nodes, including common iliac) using computerized stratified block randomization, stratified by Gleason score, type of androgen deprivation, prostate-specific antigen at diagnosis, and prior transurethral resection of the prostate. All patients received image-guided, intensity-modulated radiotherapy and minimum 2 years of androgen deprivation therapy. The primary end point was 5-year biochemical failure-free survival (BFFS), and secondary end points were disease-free survival (DFS) and overall survival (OS).

Results: From November 2011 to August 2017, a total of 224 patients were randomly assigned (PORT = 114, WPRT = 110). At a median follow-up of 68 months, 36 biochemical failures (PORT = 25, WPRT = 7) and 24 deaths (PORT = 13, WPRT = 11) were recorded. Five-year BFFS was 95.0% (95% CI, 88.4 to 97.9) with WPRT versus 81.2% (95% CI, 71.6 to 87.8) with PORT, with an unadjusted hazard ratio (HR) of 0.23 (95% CI, 0.10 to 0.52; < .0001). WPRT also showed higher 5-year DFS (89.5% 77.2%; HR, 0.40; 95% CI, 0.22 to 0.73; = .002), but 5-year OS did not appear to differ (92.5% 90.8%; HR, 0.92; 95% CI, 0.41 to 2.05; = .83). Distant metastasis-free survival was also higher with WPRT (95.9% 89.2%; HR, 0.35; 95% CI, 0.15 to 0.82; = .01). Benefit in BFFS and DFS was maintained across prognostic subgroups.

Conclusion: Prophylactic pelvic irradiation for high-risk, locally advanced prostate cancer improved BFFS and DFS as compared with PORT, but OS did not appear to differ.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1200/JCO.20.03282DOI Listing
January 2021

Regorafenib-Associated Acute Pancreatitis Diagnosed on 18F-FDG PET/CT.

Clin Nucl Med 2020 Dec 7. Epub 2020 Dec 7.

From the Department of Nuclear Medicine and Molecular Imaging, Tata Memorial Hospital, HBNI, Mumbai, India.

A 23-year-old man with metastatic osteosarcoma, with disease progression on conventional chemotherapy, was treated with regorafenib, a multikinase inhibitor. After treatment for 6 months with regorafenib, F-FDG PET/CT scan demonstrated FDG uptake in a necrotic space-occupying lesion involving tail of pancreas. After imaging, patient described symptoms of epigastric pain with elevated serum amylase and lipase levels, confirming diagnosis of regorafenib-induced pancreatitis, because patient had no other causative factors of pancreatitis. Physicians should be aware of rare and possibly clinically silent adverse effects of tyrosine kinase inhibitors, like acute pancreatitis, and recognize the F-FDG PET/CT findings to guide appropriate clinical management.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/RLU.0000000000003449DOI Listing
December 2020

Prognostic value of imaging-based parameters in patients with intermediate-stage hepatocellular carcinoma undergoing transarterial radioembolization.

Nucl Med Commun 2021 Mar;42(3):337-344

Departments of Nuclear Medicine and Molecular Imaging.

Objective: Patients with inoperable multilobar hepatocellular carcinoma (HCC) Barcelona Clinic Liver Cancer (BCLC) stage B, who have failed other liver-directed treatment options, are ideal candidates for transarterial radioembolization (TARE) with Yttrium-90 (Y-90)-labeled glass spheres. There is limited data regarding variables that impact the prognosis and outcome in these patients. 99mTc-MAA scan for lung shunt fraction (LSF) and 18F-FDG PET/CT are performed during initial workup. We, therefore, decided to assess the prognostic impact of LSF and metabolic parameters, such as maximum SUVmax, MTV and TLG in patients undergoing TARE for HCC.

Methods: We retrospectively analyzed 64 patients of HCC, between January 2010 and December 2016, deemed suitable for TARE. Pre-TARE LSF was computed on 99mTc MAA scan, and SUVmax, MTV and TLG on fluoro-deoxyglucose positron emission tomography/computed tomography were measured using automated software by 3D region of interest. LSF and PET parameters were stratified using optimal cut-offs derived from receiver operating curve analysis. Survival curves for the groups were estimated using the Kaplan-Meier method and were compared using log-rank test.

Results: Overall survival (OS) was 15 months. In univariate analysis, high LSF (greater than 7.19), MTV and TLG were statistically significant and were associated with poor OS. In multivariate analysis, TLG (P value 0.044), MTV (P value 0.290) and LSF (P value 0.010) were independent predictors of outcome, after adjustment for significant univariate variables. However, SUVmax was not statistically significant for OS.

Conclusions: LSF, MTV and TLG are significant independent prognostic indicators of outcome in patients undergoing TARE for HCC.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/MNM.0000000000001334DOI Listing
March 2021

Sentinel Node Biopsy Versus Low Axillary Sampling in Predicting Nodal Status of Postchemotherapy Axilla in Women With Breast Cancer.

JCO Glob Oncol 2020 10;6:1546-1553

Department of Breast Surgical Oncology, Tata Memorial Centre, Homi Bhabha National Institute, Mumbai, India.

Purpose: We tested low axillary sampling (LAS) and sentinel node biopsy (SNB) performed in the same patient to predict axillary nodal status post-neoadjuvant chemotherapy (NACT) in women undergoing elective breast surgery, clinically N0 after NACT.

Patients And Methods: A total of 751 women clinically node negative post-NACT underwent LAS (excision of lymph node [LN] and fat below first intercostobrachial nerve). Of these women, 730 also underwent SNB by dual technique (methylene blue plus radioisotope). SNB (defined as targeted plus palpable LNs) and LAS specimens were distinctly examined for metastasis. All patients underwent completion axillary lymph node dissection. Post-NACT, 290 (38.6%) of 751 women had residual positive lymph nodes on pathology.

Results: The median clinical tumor size was 5 cm (range, 1-15 cm), and 533 (71%) of patients were N1 or N2 at presentation. Targeted sentinel node (SN) identification was 85.7% (626 of 730; median, two LNs); SN with palpable nodes was found in 95.2% (695 of 730; median, five LNs); LAS node was identified in 98.5% (740 of 751; median, seven LNs). In all but one case, the SN was found within the LAS specimen. The false negative rate (FNR) of SNB (blue, hot, and adjacent palpable nodes) was 19.7% (47 of 238; one-sided 95% CI upper limit, 24.0), compared with an FNR of 9.9% for LAS (29 of 292; one-sided 95% CI upper limit, 12.8; < .001). If SNB was confined to blue/hot node, excluding adjacent palpable nodes, the FNR was 31.6% (74 of 234; one-sided 95% CI upper limit, 36.6). The FNR could be brought down to < 8.8% if three or more LNs were identified by LAS.

Conclusion: LAS is superior to SNB in identification rate, FNR, and negative predictive value in predicting node-negative axilla post-NACT. LAS can be safely used to predict negative axilla with < 10% chance of leaving residual disease.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1200/GO.20.00246DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7605370PMC
October 2020

Reactor produced [Cu]CuCl as a PET radiopharmaceutical for cancer imaging: from radiochemistry laboratory to nuclear medicine clinic.

Ann Nucl Med 2020 Dec 13;34(12):899-910. Epub 2020 Oct 13.

Radiopharmaceuticals Division, Bhabha Atomic Research Centre, Trombay, Mumbai, 400085, India.

Objective: Copper-64 is a useful theranostic radioisotope that is attracting renewed interest from the nuclear medicine community in the recent times. This study aims to demonstrate the utility of research reactors to produce clinical-grade Cu via Cu(n,γ)Cu reaction and use it in the form of [Cu]CuCl as a radiopharmaceutical for PET imaging of cancer in human patients.

Methods: Copper-64 was produced by irradiation of natural CuO target in a medium flux research reactor. The irradiated target was radiochemically processed and detailed quality control analyses were carried out. Sub-acute toxicity studies were carried out with different doses of Cu in Wistar rats. The biological efficacy of the radiopharmaceutical was established in preclinical setting by biodistribution studies in melanoma tumor bearing mice. After getting regulatory approvals, [Cu]CuCl formulation was clinically used for PET imaging of prostate cancer and glioblastoma patients.

Results: Large-scale (~ 30 GBq) production of Cu could be achieved in a typical batch and it was adequate for formulation of clinical doses for multiple patients. The radiopharmaceutical met all the purity requirements for administration in human subjects. Studies carried out in animal model showed that the toxicity due to "cold" Cu in clinical dose of [Cu]CuCl for PET scans would be negligible. Clinical PET scans showed satisfactory uptake of the radiopharmaceutical in the primary cancer and its metastatic sites.

Conclusions: To the best of our knowledge, this is the first study on use of reactor produced [Cu]CuCl for PET imaging of cancer in human patients. It is envisaged that this route of production of Cu would aid towards affordable availability of this radioisotope for widespread clinical use in countries with limited cyclotron facilities.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s12149-020-01522-2DOI Listing
December 2020

Comparison of predicted postoperative forced expiratory volume in the first second (FEV1) using lung perfusion scintigraphy with observed forced expiratory volume in the first second (FEV1) post lung resection.

World J Nucl Med 2020 Apr-Jun;19(2):131-136. Epub 2020 Jan 29.

Department of Nuclear Medicine and Molecular Imaging, Tata Memorial Hospital, Homi Bhabha National Institute, Mumbai, Maharashtra, India.

Lung perfusion scintigraphy is done as a part of preoperative evaluation in lung cancer patients for the prediction of postoperative forced expiratory volume in the first second (FEV1). This study was performed to see the accuracy of prediction of postoperative FEV1 by perfusion scintigraphy for patients undergoing lobectomy/pneumonectomy by comparing it with actual postoperative FEV1 obtained by spirometry 4-6 months after surgery. We retrospectively reviewed 50 surgically resected lung cancer patients who underwent preoperative spirometry, lung perfusion study, and postoperative spirometry. Pearson's correlation coefficient was used to evaluate the relationship between predicted postoperative FEV1 (PPO FEV1) by lung perfusion scintigraphy and postoperative actual FEV1 measured by spirometry. Agreement between the two methods was analyzed with Bland-Altman method. The correlation between the PPO FEV1 and actual postoperative FEV1 was statistically significant (r = 0.847, = 0.000). The correlation was better for pneumonectomy compared to lobectomy (r = 0.930 [P = 0.000] vs. 0.792 [P = 0.000]). The agreement analysis showed a mean difference of -0.0558 with a standard deviation (SD) of 0.284. The limits of agreement vary over a wide range from --0.625 to 0.513 L (mean ± 2 SD) for the entire group. For pneumonectomy, the mean difference was -0.0121 and SD 0.169 with limits of agreement varying between -0.30 L and 0.30 L. For lobectomy, the mean difference was -0.0826 and SD 0.336 with limits of agreement varying between -0.755 L and 0.590 L. Postoperative FEV1 predicted using lung perfusion scintigraphy shows good correlation with actual postoperative FEV1 and shows reasonably good agreement in patients undergoing pneumonectomy. The limits of agreement appear to be clinically unacceptable in patients undergoing lobectomy, where single-photon emission computed tomography (SPECT) or SPECT/CT techniques may improve prediction.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.4103/wjnm.WJNM_59_19DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7478303PMC
January 2020

Role of 18F-FDG PET/CT in restaging of esophageal cancer after curative-intent surgical resection.

Nucl Med Commun 2020 Sep;41(9):959-964

Tata Memorial Hospital, Homi Bhabha National Institute, Mumbai, India.

Objective: The aim of the study was to evaluate diagnostic performance of FDG PET-CT in suspected recurrence of carcinoma esophagus after curative-intent surgical resection and impact of FDG PET-CT on intended management.

Material And Methods: This was retrospective study of patients with clinical or radiological suspicion of recurrent esophageal carcinoma who were referred for PET-CT from January 2006 to December 2017. Diagnostic performance of PET-CT was evaluated for disease recurrence and its impact on management decisions. PET-CT findings were confirmed with tissue diagnosis. When tissue diagnosis was not available clinical and radiological follow-up was used as reference standard.

Results: Relevant clinical data were available in 68 patients which were considered for analysis. In 91% (62/68) patients FDG PET-CT findings were suggestive of disease recurrence. Histopathological confirmation was available in 43 patients, whereas in remaining patients recurrence was confirmed by radiological and clinical follow-up. Forty percent (28/68) patients were detected with distant metastases. Sensitivity, specificity, positive and negative predictive values of FDG PET-CT was found to be 98.4, 80, 98 and 80% with accuracy of 97%. Change in management was observed in 41% (28/68) of patients from salvage radiotherapy/surgery to palliative chemotherapy/best supportive care based on evidence of distant metastases seen on FDG PET-CT.

Conclusion: FDG PET-CT is highly sensitive in detection of recurrent disease in esophageal cancer patients after surgical resection. It can detect distant metastases in high proportion of patients thus changing the intent of management from radical salvage to palliative chemotherapy/best supportive care.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/MNM.0000000000001229DOI Listing
September 2020

Does 68Ga-DOTA-NOC-PET/CT impact staging and therapeutic decision making in pulmonary carcinoid tumors?

Nucl Med Commun 2020 Oct;41(10):1040-1046

Department of Nuclear Medicine and Molecular Imaging.

Objective: Purpose of this study was to assess the utility of Ga-DOTA-NOC-PET/computed tomography (CT) (Ga-NOC-PET) in tumor detection, pathological differentiation and baseline staging of pulmonary carcinoids as well as to study its impact on therapeutic decision making.

Patients And Methods: Patients who underwent a Ga-NOC-PET for initial evaluation of bronchopulmonary carcinoid tumors from August 2014 to December 2019 were included. Detection rate of Ga-NOC-PET for the primary lesion was calculated by visual estimation of tracer uptake as per Krenning score. SUVmax of typical and atypical carcinoid tumors was measured and difference compared using nonparametric statistical tests. Proportion of patients with distant metastases was also calculated and its impact on intended treatment was assessed.

Results: Imaging, histopathology and treatment details of 119 patients were available for analysis. Majority of tumors had an endobronchial location (74.7%) and showed histopathologic features of typical carcinoid (82.3%). Ga-NOC-PET showed a detection rate/sensitivity of 92.4%. Oncocytic variant on histopathology and smaller tumor size accounted for majority of negative results. Typical carcinoids showed significantly higher SUVmax than atypical tumors (median SUVmax 38.4 vs. 15.7, P = 0.002). Metastases to distant sites outside the thorax were seen in 14 patients (11.7%), primarily in liver and bones changing the intent of treatment from surgery to systemic therapy.

Conclusion: Ga-NOC-PET detects asymptomatic distant metastatic disease in a sizeable number of patients (11.7%) with pulmonary carcinoid and thus contribute to clinical management by precluding futile surgeries. It shows a high sensitivity for tumor detection and can help differentiate between typical and atypical carcinoid variants by virtue of their variable tracer uptake. PET/CT using Ga-labeled DOTA peptides should be an integral part of diagnostic workup of patients with lung carcinoid.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/MNM.0000000000001248DOI Listing
October 2020

Diagnostic Yield of Extensive Systemic Staging Including Whole-body 18F-fluoro-deoxy-glucose Positron Emission Tomography With or Without Computed Tomography in Patients With Primary Central Nervous System Lymphoma: Systematic Review and Meta-analysis.

Clin Lymphoma Myeloma Leuk 2020 Nov 6;20(11):e836-e845. Epub 2020 Jul 6.

Department of Nuclear Medicine and Molecular Imaging, ACTREC/TMH, Tata Memorial Centre, Homi Bhabha National Institute (HBNI), Mumbai, India.

The extent of staging required to evaluate for systemic involvement in patients with primary central nervous system lymphoma (PCNSL) remains controversial. Eligible studies reporting on diagnostic yield of extensive systemic staging, including pre-treatment whole-body 18F-fluoro-deoxy-glocose positron emission tomography with or without computed tomography, in immuno-competent adults with PCNSL were identified through systematic literature search. Diagnostic yield was defined as the proportion of patients with abnormal test results outside the neuraxis that led to detection of concordant systemic high-grade lymphoma on an individual patient basis (true positives). Data were pooled using random-effects model to produce summary estimates with 95% confidence intervals (CIs). Weighted-mean pooled analysis involving 1099 patients from 14 primary studies provided an overall diagnostic yield of 6% (95% CI, 4%-8%) for extensive systemic staging in PCNSL with implications for diagnosis, prognosis, and therapy. Summary estimates of false positivity were just marginally lower at 5% (95% CI, 3%-8%) for such systemic staging.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.clml.2020.06.019DOI Listing
November 2020

Outcomes of T-lymphoblastic lymphoma treated with pediatric ALL-like protocol.

Indian J Cancer 2020 Jul-Sep;57(3):262-266

Department of Radiation Oncology, Tata Memorial Hospital, Mumbai, Maharashtra, India.

Background: The management of T-lymphoblastic lymphoma (T-LBL) in adults poses uncertainties, including optimal chemotherapy regimen, need for radiotherapy, and the benefit of stem cell transplant. This retrospective case series investigated the efficacy of the pediatric BFM-90 regimen in adult patients and evaluated the role of early response assessment by positron emission tomography with computed tomography (PET-CT) in predicting outcomes.

Methods: Patients aged 15 years or older with T-LBL diagnosed at Tata Memorial Hospital, Mumbai, India were given chemotherapy according to the European BFM-90 protocol (n = 38). The patients were evaluated for early response by interim PET-CT, post-induction and monitored for toxicity and long-term outcomes.

Results: Thirty-eight consecutive patients (median age 23.5 years) were analyzed. After a median follow-up of 33.5 (1-77) months, following induction, 35 out of 38 patients (92.1%) had achieved complete response (CR) on PET-CT. Thirty (78.9%) patients treated according to BFM-90 were alive in first remission. Three-year event-free survival for those with CR on PET-CT was 78%, against no survivors for those who remained PET-positive.

Conclusion: This study demonstrates the feasibility and efficacy of BFM-90 approach in adults with T-LBL. We found an early PET response to be highly predictive of outcome.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.4103/ijc.IJC_616_18DOI Listing
December 2020

Prognostic value of metabolic parameters measured by F-fluorodeoxyglucose positron emission tomography-computed tomography in surgically resected non-small cell lung cancer patients.

World J Nucl Med 2020 Jan-Mar;19(1):8-14. Epub 2020 Feb 27.

Department of Nuclear Medicine and Molecular Imaging, Tata Memorial Hospital, Homi Bhabha National Institute, Mumbai, Maharashtra, India.

F-fluorodeoxyglucose positron emission tomography-computed tomography-derived metabolic parameters can play a role in prognostication. We investigated the prognostic value of various metabolic parameters such as maximum standardized uptake value (SUV), mean SUV (SUV), whole-body metabolic tumor volume (WBMTV), and whole-body total lesion glycolysis (WBTLG) in surgically resected non-small cell lung cancer (NSCLC) patients. We retrospectively reviewed 153 patients with NSCLC who underwent surgical resection. The SUV, SUV, WBMTV, and WBTLG of the tumor were measured. Continuous PET parameters were stratified by receiver operating characteristic curve analysis. Prognostic factors were estimated using the Kaplan-Meier method and Cox proportional hazards model. The median follow-up was 36.9 months. Fifty-six patients died and 78 patients had recurrence. On univariate analysis, tumor-node-metastasis (TNM) stage; male sex; no adjuvant treatment; and higher SUV, SUV, WBMTV, and WBTLG were statistically significant and were associated with poor overall survival (OS). TNM stage; no adjuvant treatment; and higher SUV, SUV mean, WBMTV, and WBTLG were statistically significant and were associated with poor disease-free survival (DFS). On multivariate analysis, higher WBTLG (hazard ratio [HR] = 3.08, = 0.007) for DFS and higher WBTLG (HR = 2.70, = 0.041) and TNM staging (HR = 1.63, = 0.035) for OS were statistically significant. Whole-body tumor burden assessment with TLG has independent prognostic value in patients with operated lung cancer. Incorporation of TLG into clinical practice can identify patients benefitted from additional therapy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.4103/wjnm.WJNM_26_19DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7067134PMC
February 2020

Renal granulomas mimicking as malignant renal masses on F18 FDG PET/CT in a case of urothelial carcinoma.

Eur J Nucl Med Mol Imaging 2020 11 10;47(12):2930-2931. Epub 2020 Mar 10.

Department of Nuclear Medicine and Molecular Imaging, Tata Memorial Hospital, Homi Bhabha National Institute, E. Borges Road, Parel, Mumbai, 400 012, India.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00259-020-04728-8DOI Listing
November 2020

Study protocol of a randomised controlled trial of prostate radiotherapy in high-risk and node-positive disease comparing moderate and extreme hypofractionation (PRIME TRIAL).

BMJ Open 2020 02 28;10(2):e034623. Epub 2020 Feb 28.

Division of Uro-Oncology, Tata Memorial Centre, Mumbai, India.

Introduction: There has been an interest in studying the efficacy of extreme hypofractionation in low and intermediate risk prostate cancer utilising the low alpha/beta ratio of prostate. Its role in high-risk and node-positive prostate cancer, however, is unknown. We hypothesise that a five-fraction schedule of extreme hypofractionation will be non-inferior to a moderately hypofractionated regimen over 5 weeks in efficacy and will have acceptable toxicity and quality of life while reducing the cost implications during treatment.

Methods And Analysis: This is an ongoing, non-inferiority, multicentre, randomised trial (NCT03561961) of two schedules for National Cancer Control Network high-risk and/or node-positive non-metastatic carcinoma of the prostate. The standard arm will be a schedule of 68 Gy/25# over 5 weeks while the test arm will be extremely hypofractionated radiotherapy with stereotactic body radiation therapy to 36.25 Gy/5# (7 to 10 days). The block randomisation will be stratified by nodal status (N0/N+), hormonal therapy (luteinizing hormone-releasing hormone therapy/orchiectomy) and centre. All patients will receive daily image-guided radiotherapy.The primary end point is 4-year biochemical failure free survival (BFFS). The power calculations assume 4-year BFFS of 80% in the moderate hypofractionation arm. With a 5% one-sided significance and 80% power, a total of 434 patients will be randomised to both arms equally (217 in each arm). The secondary end points include overall survival, prostate cancer specific survival, acute and late toxicities, quality of life and out-of-pocket expenditure.

Discussion: The trial aims to establish a therapeutically efficacious and cost-efficient modality for high-risk and node-positive prostate cancer with an acceptable toxicity profile. Presently, this is the only trial evaluating and answering such a question in this cohort.

Ethics And Dissemination: The trial has been approved by IEC-III of Tata Memorial Centre, Mumbai.

Trial Registration Number: Registered with CTRI/2018/05/014054 (http://ctri.nic.in) on 24 May 2018.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1136/bmjopen-2019-034623DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7050316PMC
February 2020

Prognostic Value of 18F-FDG PET/CT-Metabolic Parameters at Baseline and Interim Assessment in Pediatric Anaplastic Large Cell Lymphoma.

Clin Nucl Med 2020 Mar;45(3):182-186

From the Departments of Nuclear Medicine and Molecular Imaging.

Introduction: The event-free survival in pediatric anaplastic large cell lymphoma (ALCL) remains at 70% irrespective of the diverse chemotherapy regimens used. There is lack of valid prognostic factors identifying high-risk patients. We investigated the prognostic value of baseline metabolic parameters and interim response on F-FDG PET/CT in pediatric ALCL patients.

Methods: We retrospectively reviewed 40 pediatric ALCL patients with paired F-FDG PET/CT and treated uniformly on vinblastine-based institution protocol. The SUVmax, SUVmean, metabolic tumor volume (MTV), and total lesion glycolysis of the lymphomatous lesion were measured. Continuous PET parameters were stratified by their median values. Deauville scoring system was used to assess response to chemotherapy in the interim scan. Prognostic factors for overall survival (OS) and disease-free survival (DFS) were estimated using the Kaplan-Meier method, log-rank test, and Cox proportional hazards model.

Results: At median follow-up of 52 months, 13 patients died and 13 had recurrence. On univariate analysis, higher whole-body MTV (WBMTV) and partial response on interim scan were statistically associated with OS. High-risk features, WBMTV, and partial response were statistically associated with DFS. On multivariate analysis combining baseline characteristics and interim response, interim response (hazard ratio, 3.56; P = 0.034) was statistically significant for OS. Multivariate analysis for DFS using only baseline characteristics revealed WBMTV as statistically significant (hazard ratio, 4.08; P = 0.035), but none of the parameters was statistically significant when baseline characteristics and interim response were evaluated together.

Conclusions: Whole-body tumor burden assessment with MTV and interim response may help to identify high-risk patients who might get benefitted from intensive therapy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/RLU.0000000000002927DOI Listing
March 2020

Role of positron emission tomography-contrast enhanced computed tomography in locally advanced gallbladder cancer.

J Hepatobiliary Pancreat Sci 2020 Apr 17;27(4):164-170. Epub 2020 Feb 17.

Department of Radiation Oncology, Tata Memorial Hospital, Mumbai, India.

Introduction: This study aims to define the role of flurodeoxyglucose ( -FDG) positron emission tomography-contrast enhanced computed tomography (PETCECT) scan in upstaging disease in patients with locally advanced gallbladder cancer (LAGBC).

Methods: An analysis of a prospectively maintained database of gallbladder cancer (GBC) patients was performed. Patients found to have locally advanced (T3 and/or T4 or N+) but non-metastatic disease on initial imaging, either a contrast enhanced computed tomography (CECT) or a magnetic resonance imaging (MRI) scan, underwent an additional PETCECT for staging and the results impacting treatment decision were recorded.

Results: One hundred and three patients of LAGBC underwent CECT/MRI and PETCECT. 48/103 (46.6%) were found to be upstaged to stage IV after PETCECT. The most common metastatic site was non-regional retroperitoneal lymph nodes (12 patients, 11.7%) followed by satellite lesions in liver (11, 10.7%). Fourteen (13.6%) patients had equivocal findings on PET scan that required confirmation by tissue sampling out of which 10 (71.4%) were subsequently found to have metastatic disease. The only statistically significant factor predicting distant spread on PETCECT was the presence of loco-regional nodes on CT scan (odds ratio 6.15, P = .006).

Conclusion: PETCECT is a valuable tool to rule out metastatic disease in patients presenting with LAGBC.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/jhbp.712DOI Listing
April 2020

Differentiating dural metastases from meningioma: role of 68Ga DOTA-NOC PET/CT.

Nucl Med Commun 2020 Apr;41(4):356-362

Departments of Nuclear Medicine and Molecular Imaging.

Objective: To assess the ability of Ga DOTA-NOC PET/computed tomography (CT) to differentiate dural metastases from meningioma.

Patients And Methods: Patients who underwent a Ga DOTA-NOC PET/CT for differentiating meningiomas from dural metastases were included in the study. A visual score was assigned to the dural lesions (visual score - 1 to 3) in relation to the uptake in liver and spleen and variation in the visual score was evaluated. SUVmax of the dural lesions was also noted and difference in the values of the two pathologies were compared for statistical significance using nonparametric statistical tests. Final diagnosis was decided by histopathological confirmation whenever available.

Results: Imaging, histopathology or follow-up data of 42 patients was available for analysis. Meningioma was the final diagnosis in 31 (73.8%) patients, whereas dural metastases were diagnosed in 9 (21.4%) patients. In two patients, histopathology revealed inflammatory pseudotumor and hemangioblastoma. Meningiomas showed intense tracer uptake in 30/31 patients (visual score 3). All metastatic lesions showed some degree of tracer uptake though the intensity was lesser compared to meningioma (visual score 1, 2). Meningiomas showed a significantly higher median SUV max value compared to metastases (12.7 vs. 6.0, P = 0.001).

Conclusion: Meningiomas can be differentiated from dural metastases by virtue of their higher uptake of Ga-labeled DOTA peptides reflecting higher SSTR expression. An asymptomatic meningeal based lesion with a high visual score (Visual score 3) has a very high probability to be a meningioma rather than dural metastasis.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/MNM.0000000000001155DOI Listing
April 2020

Software development for hepatopulmonary shunt estimation by gamma camera method in transarterial radioembolization.

World J Nucl Med 2019 Oct-Dec;18(4):366-372. Epub 2019 Dec 18.

Department of Nuclear Medicine and Molecular Imaging, Tata Memorial Hospital, Mumbai, Maharashtra, India.

Trans-arterial radioembolization (TARE) is an established treatment for inoperable hepatocellular carcinoma and liver metastases from Carcinoma of gastrointestinal tract. Radiation-induced toxicity to the lung parenchyma is the dose-limiting factor in TARE. Pretreatment hepatopulmonary shunt (HPS) is estimated by gamma camera method by transarterial administration of 370MBq Tc macro aggregated albumin. We have developed HPS software on XELERIS-1.123 workstation, GE medical systems, Milwaukee, USA, for accurate calculation of HPS. This software has also been tested on a higher version of XELERIS workstation, and it has been found to work well in all versions.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.4103/wjnm.WJNM_115_18DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6945361PMC
December 2019

Performance characteristic evaluation of a bismuth germanate-based high-sensitivity 5-ring discovery image quality positron emission tomography/computed tomography system as per National Electrical Manufacturers Association NU 2-2012.

World J Nucl Med 2019 Oct-Dec;18(4):351-360. Epub 2019 Dec 18.

Department of Nuclear Medicine and Molecular Imaging, Tata Memorial Hospital, Mumbai, Maharashtra, India.

National Electrical Manufacturers Association (NEMA) provides guidelines to assess the performance of Positron Emission Tomography (PET). A PET/CT scanner, Discovery IQ, GE Medical systems, Milwaukee, USA was installed in our department which has high a sensitivity PET component. We have performed the NEMA NU-2 2012 quality control tests to evaluate this system on site before clinical use. Performance measurements of the PET scanner were made using the NEMA NU2-2012 procedures for spatial resolution, scatter fraction, sensitivity, count rate loss and random coincidence estimation, Noise Equivalent Count Rate (NECR) and image quality. As per NU2 2012, spatial resolution was measured at 1 cm, 10 cm and 20 cm vertically from the centre and at each of these points resolution was measured at tangential, radial and axial directions. Sensitivity was measured at centre and 10 cm off center vertically from the center. The system sensitivity is reported as an average of the two measured values. Scatter fraction and NECR measurements, Image quality test was also performed. The tangential, radial and axial FWHM were 4.99 mm, 4.20 mm and 4.79 mm at 1 cm off centre, 5.49 mm, 4.69 mm and 4.81 mm at 10 cm off centre and 7.99 mm, 5.07 mm and 4.95 mm at 20 cm off centre respectively. The absolute sensitivity of this scanner was found to be 20.1 cps/kBq. The scatter fraction calculated from the decay method was 37.94% and NECR was 125 kcps. The peak NECR was achieved at activity concentration of 8.7 KBq/ml and the count loss below the peak NECR was found to be 0.68%. Image quality test for, contrast recovery, background variability and lung error residual mean met all specifications. Overall PET performance of Discovery IQ whole-body scanner was satisfactory and the scanner met all the performance specifications required by NEMA 2012.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.4103/wjnm.WJNM_72_18DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6945355PMC
December 2019

FDG PET/CT of Primary Ewing Sarcoma of IVC.

Clin Nucl Med 2020 Feb;45(2):e112-e114

From the Department of Nuclear Medicine and Molecular Imaging, Tata Memorial Hospital, Mumbai, India.

Secondary involvement of inferior vena cava is a common presentation in aggressive solid malignancies, especially arising from kidneys, adrenals, and hepatobiliary system, mostly resulting from local infiltration. Rarely, primary tumors are seen arising from vascular tissue. The Ewing family of tumors commonly arises from bone, but there is a high propensity of these tumors to originate from nonosseous sites of mesenchymal cell origin. We would herewith demonstrate a rare presentation of Ewing sarcoma, seen originating from inferior vena cava, presenting as extensive intravascular tumor thrombosis, evaluated on FDG PET/CT imaging in a 12-year-old girl.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/RLU.0000000000002878DOI Listing
February 2020

Utility of flouro-deoxy-glucose positron emission tomography/computed tomography in the diagnostic and staging evaluation of patients with primary CNS lymphoma.

CNS Oncol 2019 12 29;8(4):CNS46. Epub 2019 Nov 29.

Department of Radiation Oncology, TMH/ACTREC, Tata Memorial Centre, Homi Bhabha National Institute (HBNI), Mumbai 400012, India.

To prospectively assess the clinical utility of pretreatment flouro-deoxy-glucose positron emission tomography/computed tomography (18F-FDG-PET/CT) in patients with primary central nervous system (CNS) lymphoma (PCNSL). Patients with suspected/proven PCNSL underwent baseline whole-body 18F-FDG-PET/CT. Maximum standardized uptake value and tumor/normal tissue ratios were compared between CNS lymphoma and other histological diagnoses. The mean maximum standardized uptake value (27.5 vs 18.2; p = 0.001) and mean tumor/normal tissue ratio (2.34 vs 1.53; p < 0.001) of CNS lymphoma was significantly higher than other histologic diagnoses. Five of 50 (10%) patients with biopsy-proven CNS lymphomas had pathologically increased FDG-uptake at extraneuraxial sites uncovering systemic lymphoma. Pretreatment whole-body 18F-FDG-PET/CT provides valuable complementary information in the diagnostic and staging evaluation of patients with PCNSL to guide therapeutic decision-making.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2217/cns-2019-0016DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6912853PMC
December 2019

Assessment of the impact of 2015 American Thyroid Association guidelines in management of differentiated thyroid cancer patients.

Eur J Nucl Med Mol Imaging 2020 03 9;47(3):547-553. Epub 2019 Nov 9.

Department of Nuclear Medicine and Molecular Imaging, Tata Memorial Hospital, Homi Bhaba National Institute (HBNI), E. Borges Road, Parel, Mumbai, 400 012, India.

The 2015 American Thyroid Association (ATA) guideline have suggested modifications in the risk stratification (RS) for differentiated thyroid cancer (DTC) patients, introduced the concept of dynamic risk stratification (DRS) and redefined the role of radioactive iodine (RAI) in treatment algorithm. The aim of this retrospective audit was to assess the practical implications of these modifications in management of DTC.

Methods: A total of 138 DTC patients were stratified according to ATA 2009 and 2015 guidelines into low (LR), intermediate (IR) and high (HR) risk groups. Change in RS and in intention of RAI use was calculated. Deviation in administered RAI dosage from the guidelines was assessed. 1-year follow-up data was audited to assess how the DRS modified the initial risk estimate.

Results: A total of 11.6% of patients changed their RS categories in 2015 guidelines. A total of 10.1% got upstaged to HR, and 1.4% got downstaged to LR. In 2.17% of patients' intention of RAI use changed to remnant ablation from adjuvant therapy and 65% of the LR patients won't require any RAI therapy. A total of 26.7% of patients had received significantly more RAI dosage according to ATA 2015. At 1-year follow-up according to DRS 84% of LR, 75% of IR and 44% of HR patients showed excellent response (ER).

Conclusion: More patients changed RS to HR than to LR. Intention of RAI use changed in only a small number of patients. Significantly higher dosage of RAI is being administered to patients in current practice. The effect of DRS in modifying the initial RS was most prominent in IR, with most showing ER to initial therapy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00259-019-04582-3DOI Listing
March 2020

68Ga-prostate-specific membrane antigen PETCT-based response to androgen deprivation therapy in patients with prostate cancer.

Nucl Med Commun 2019 Dec;40(12):1283-1288

Nuclear Medicine, Tata Memorial Centre and Advanced Centre for Treatment Research and Education in Cancer (ACTREC), Homi Bhabha National Institute, Mumbai, India.

Objective: To assess the response of castration-naïve prostate cancer to androgen deprivation therapy (ADT) in Ga-PSMA PETCT, and test the hypothesis of differential response in primary, nodal and metastatic lesions.

Materials/methods: Patients with adenocarcinoma prostate with baseline Ga-prostate-specific membrane antigen (PSMA) PETCT scan, and response scan after 3-12 months of ADT from 2014 to 2017 were analyzed. Change in radiotracer uptake in the prostate, involved regional nodes and distant metastasis was semiquantitatively assessed in paired scans using maximum standardized uptake value (SUVmax). Response was categorized into complete or partial response (CR, PR) or stable disease or progressive disease (SD, PD), and correlated with known prognostic factors.

Results: Total 86 scans of 43 patients (17 metastatic, M+) were analyzed. After median 6 months of ADT, 0% primary, 23.3% nodes and 17.6% metastases showed CR; 18.6% primary, 8.3% nodes and 35% metastases showed PD. Prostate response was not significantly associated with any prognostic factor. Nodal response was higher in M0 than in M+ disease (CR 37 vs 4%, P = 0.003). Oligometastases responded better than polymetastases (CR/PR 62.5 vs 11.1%, P = 0.05). Decline in SUVmax of primary tumor correlated with decline in serum prostate-specific antigen (PSA) (90% of partial responders showed >80% decline in serum PSA vs 50% with PD, P = 0.06).

Conclusion: Primary prostatic tumor seems less likely to respond to ADT than nodal or metastatic lesions. Residual primary uptake may guide patient selection for local therapy in (oligo) metastatic prostate cancer.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/MNM.0000000000001105DOI Listing
December 2019

Granulomatous hepatitis masquerading as metastases on FDG PET/CT.

Eur J Nucl Med Mol Imaging 2020 04 22;47(4):1013-1014. Epub 2019 Oct 22.

Department of Nuclear Medicine and Molecular Imaging, Tata Memorial Hospital, E. Borges Road, Parel, Mumbai, 400012, India.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00259-019-04544-9DOI Listing
April 2020

Lung Masses of Unusual Histologies Mimicking Malignancy: Flurodeoxyglucose Positron Emission Tomography-Computed Tomography Appearance.

Indian J Nucl Med 2019 Oct-Dec;34(4):295-301

Department of Nuclear Medicine and Molecular Imaging, Tata Memorial Hospital, Homi Bhabha National Institute, Mumbai, Maharashtra, India.

18F flurodeoxyglucose positron emission tomography-computed tomography (18F FDG PET-CT) is widely used in the evaluation of patients with lung mass suspicious for malignancy. In addition to malignancy, a variety of benign neoplasms and inflammatory lesions can arise in the lungs, many of which show increased FDG concentration, thereby mimicking malignancy. Awareness of the common mimics of lung cancer and a thorough understanding of their key imaging characteristics on CT as well as FDG PET is helpful in narrowing the differential diagnosis, eventually leading to appropriate therapy. In this article, we enlist these mimics and discuss their metabolic and morphologic characteristics and provide a pathophysiological basis for their FDG uptake.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.4103/ijnm.IJNM_116_19DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6771216PMC
October 2019

Utility of FET-PET in detecting high-grade gliomas presenting with equivocal MR imaging features.

World J Nucl Med 2019 Jul-Sep;18(3):266-272

Department of Nuclear Medicine and Molecular Imaging, Tata Memorial Hospital, Homi Bhabha National University, Mumbai, Maharashtra, India.

High-grade gliomas, metastases, and primary central nervous system lymphoma (PCNSL) are common high-grade brain lesions, which may have overlapping features on magnetic resonance (MR) imaging. Our objective was to assess the utility of 18-fluoride-fluoro-ethyl-tyrosine positron emission tomography (FET-PET) in reliably differentiating between these lesions, by studying their metabolic characteristics. Patients with high-grade brain lesions suspicious for glioma, with overlapping features for metastases and PCNSL were referred for FET-PET by Neuroradiologists from Multidisciplinary Neuro-Oncology Joint Clinic. Tumor-to-contralateral white mater ratio (T/Wm) at 5 and 20 min was derived and compared to histopathology. Receiver operating characteristic curve analysis was used to find the optimal T/Wm cutoff to differentiate between the tumor types. T/Wm was higher for glial tumors compared to nonglial tumors (metastases, PCNSL, tuberculoma, and anaplastic meningioma). A cutoff of 1.9 was derived to reliably diagnose a tumor of glial origin with a sensitivity and specificity of 93.8% and 91%, respectively. FET-PET can be used to diagnose glial tumors presenting as high-grade brain lesions when MR findings show overlapping features for other common high-grade lesions.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.4103/wjnm.WJNM_89_18DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6714153PMC
September 2019

Initial experience of Ga-68 prostate-specific membrane antigen positron emission tomography/computed tomography imaging in evaluation of biochemical recurrence in prostate cancer patients.

World J Nucl Med 2019 Jul-Sep;18(3):244-250

Department of Nuclear Medicine and Molecular Imaging, Uro-Oncology Disease Management Group, Tata Memorial Hospital, Mumbai, Maharashtra, India.

Gallium-68 labeled prostate-specific membrane antigen (Ga-68 PSMA) ligand (HBED-CC) is a novel tracer used for prostate cancer imaging. The aim of the study was to investigate the performance of Ga-68 PSMA positron emission tomography/computed tomography (PET/CT) in patients with biochemical recurrence (BCR) after definitive treatment. Scans of 96 consecutive patients were analyzed. Sixty-two patients received external beam radiotherapy, 34 underwent radical prostatectomy (RP), and 20 patients were on androgen deprivation therapy. Patients with prostate-specific antigen (PSA) level ≥>0.2 ng/mL following RP and PSA rise by 2 ng/mL or more above the nadir PSA following RT (Phoenix criteria) was considered as BCR, respectively. All patients underwent contrast-enhanced PET/CT after injection of 67-111 MBq Ga-68 PSMA ligand. Detection rates were correlated with serum PSA level. Detection rate for nodal metastases was compared with CT. Results of the scan were validated by using either biopsy or follow-up imaging or clinical follow-up. Seventy-four (77%) patients showed abnormal finding in Ga-68 PSMA PET/CT. The median serum PSA level of the population was 5.5 ng/ml (range 0.2-123 ng/ml). The median PSA of the positive scans was higher than that of the negative scans (6 vs. 1.7 ng/ml) and was statistically significant ( = 0.001 by Mann-Whitney U-test). In post-RP group, the detection rates were 23%, 50%, and 82% for PSA <1, 1-2, and >2 ng/ml, respectively. For post-RT, the detection was 86%, 85%, and 95% for PSA 2-5, 5.1-10, and >10 ng/ml, respectively. PSMA PET/CT revealed nodal metastases in 52 (54%) patients while CT showed pathological nodes only in 27 (28%) patients. Overall PSMA PET/CT revealed more number of nodes than CT (111 vs. 48 nodal station). PSMA PET/CT showed relapse in prostate/prostatic bed in 26 (27%) patients, nodal metastases in 50 (52%), skeletal metastases in 20 (21%), and other sites in 4 (4%) patients. Ga-68 PSMA PET/CT has high detection rate for localizing the site of recurrence in patients with biochemical failure and is superior to CT scan in the detection of nodal disease.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.4103/wjnm.WJNM_47_18DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6714163PMC
September 2019

Evaluation of quantitative imaging parameters in head and neck squamous cell carcinoma.

Q J Nucl Med Mol Imaging 2019 Sep 5. Epub 2019 Sep 5.

Department of Radiation Oncology, Advanced Centre for Treatment Research & Education in Cancer (ACTREC), Tata Memorial Hospital (TMH), Tata Memorial Centre, Mumbai, India.

Background: Functional imaging such as 18F-fluoro-deoxy-glucose positron emission tomography/computed tomography (FDG-PET/CT), 18F-fluoro-misonidazole (F-MISO)-PET/CT, and diffusion-weighted magnetic resonance imaging (DW-MRI) can assess complex biological phenomena in tumors reflecting underlying disease biology. The aim of this prospective observational study was to correlate quantitative imaging parameters derived from pre-treatment biological imaging such as FDG-PET/CT, F-MISO-PET/CT, and DW-MRI with each other andì with clinical outcomes in patients with head and neck squamous cell carcinoma (HNSCC) treated with definitive radio(chemo)therapy.

Methods: Twenty patients with pharyngo-laryngeal cancers underwent pre-treatment biological imaging. Gross tumor volume (GTV) was delineated on axial planning CT (GTVCT). Quantitative FDG-PET/CT parameters included maximum, mean, minimum standardized uptake values (SUVmax-FDG, SUVmean-FDG, SUVmin-FDG); metabolic tumor volume (MTV); and total lesion glycolysis (TLG). F-MISO-PET/CT parameters included hypoxic tumor volume (HTV); maximum, mean, minimum SUV; and fractional hypoxic volume (FHV). Mean apparent diffusion coefficient (ADCmean) was derived from DW-MRI.

Results: There was moderately strong positive correlation (r=0.616, p=0.005) between GTVCT and MTV. HTV derived from F-MISO-PET/CT at 3-hours (HTV3hrs-F-MISO) showed strong positive correlation with GTVCT (r=0.753, p<0.0001) and MTV (r=0.796, p<0.0001) respectively. ADCmean showed strong positive correlations with SUVmean-5hrs-F-MISO (r=0.713, p=0.021) and SUVmin-5hrs-FMISO (r=0.731, p=0.016) respectively. A moderate negative correlation (r=-0.500, p=0.049) was observed between ADCmean and MTV. At a median follow up of 44 months, the 5-year Kaplan-Meier estimates of loco-regional control, disease-free survival, and overall survival were 53%, 43%, and 40% respectively. Larger volume of primary tumor (GTVCT>22cc and MTV>7.9cc) and increasing hypoxia (HTV3hr-F-MSO>4.9cc) were associated with worse outcomes.

Conclusions: Functional imaging represents an attractive and non-invasive modality to assess complex biological phenomena in solid tumors. Larger tumor volume and increasing hypoxia emerged as putative prognostic imaging biomarkers in HNSCC.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.23736/S1824-4785.19.03179-0DOI Listing
September 2019

Incidental Detection of Pleomorphic Sarcoma on 68Ga-PSMA PET/CT in a Patient With Prostate Cancer.

Clin Nucl Med 2020 Feb;45(2):e120-e121

From the Departments of Nuclear Medicine and Molecular Imaging.

Ga prostate-specific membrane antigen (PSMA) PET/CT is used in the staging, evaluation of biochemical recurrence, and response assessment of patients with prostate cancer. In addition to the PSMA-expressing prostate cancer cells, Ga-PSMA binds to the neovasculaature of various other solid tumors and benign lesions. We report a case of a 72-year-old man with recently diagnosed adenocarcinoma of prostate, incidentally found to have pleomorphic sarcoma on the staging Ga-PSMA PET/CT.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/RLU.0000000000002760DOI Listing
February 2020