Publications by authors named "Gozde Yazici"

47 Publications

The evolution of bone marrow signal changes at the skull base in nasopharyngeal carcinoma patients treated with radiation therapy.

Radiol Med 2021 Mar 31. Epub 2021 Mar 31.

Department of Radiology, University of Illinois at Chicago, Chicago, IL, USA.

Background: Clival infiltration is frequently seen in nasopharyngeal carcinoma (NPC) and the resultant bone marrow signal changes (BMSC) can persist even after complete tumor response to the radiation therapy (RT). The differentiation of those residual BMSC from recurrent/persistent disease may be challenging. We performed serial analysis of the clival BMSC after RT, to define an expected temporal evolution of those signal changes during the follow-up.

Materials And Methods: Serial MRI studies of 50 NPC patients (with or without initial clival infiltration) who had undergone RT were retrospectively examined. Abnormal clival BMSC and contrast enhancement (CE) were evaluated on each follow-up scan. Duration of BMSC/CE was correlated with the degree of baseline clival involvement (BCID), RT dose, and primary mass volume (PMV).

Results: Clival BMSC persisted without any evidence of recurrence, for a mean of 66.5 (max. 137) months (with accompanying CE for up to 125 months) in 26 patients with clival infiltration at diagnosis. Duration of BMSC and CE showed statistical correlations with PMW (p < 0.05), but not with RT dose or BCID. The rate of recurrence in clivus was 14%. New clival lesions that occurred within the first 12 months after RT (in six patients) did not develop recurrence suggesting radiation osteitis (12%).

Conclusion: After RT, residual clival medullary signal change/enhancement is seen in most NPC patients and can persist even years without recurrence.
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http://dx.doi.org/10.1007/s11547-021-01342-yDOI Listing
March 2021

In regard to Sahebjam et al.

Neuro Oncol 2021 Apr;23(4):702

Department of Radiation Oncology, Hacettepe University Medical School, Ankara, Turkey.

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http://dx.doi.org/10.1093/neuonc/noaa289DOI Listing
April 2021

In Regard to Helm et al.

Int J Radiat Oncol Biol Phys 2021 Apr;109(5):1658

Hacettepe University Faculty of Medicine, Department of Radiation Oncology, Ankara, Turkey.

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http://dx.doi.org/10.1016/j.ijrobp.2020.12.017DOI Listing
April 2021

A novel inverse optimization based three-dimensional conformal radiotherapy technique in craniospinal irradiation.

Phys Eng Sci Med 2021 Mar 8;44(1):265-275. Epub 2021 Feb 8.

Department of Radiation Oncology, Faculty of Medicine, Hacettepe University, 06100, Ankara, Turkey.

Our aim was to develop a novel inverse optimization-based three-dimensional conformal radiotherapy (i3DCRT) technique for craniospinal irradiation. The imaging data of 20 patients with medulloblastoma were used retrospectively. The first group included 10 pediatric patients with supine position treated under anesthesia/sedation, and the second group included 10 young adult/adult patients treated with prone position. Three different treatment plans were created for each patient via i3DCRT, forward-planned three-dimensional conformal radiotherapy (f3DCRT) and intensity-modulated radiotherapy (IMRT) techniques. A total dose of 36 Gy was prescribed in 20 fractions for all plans. The comparative evaluation was conducted by using the parameters of conformity-index, homogeneity-index, and doses to the target volumes and organs at risk (OARs). The plans created with i3DCRT technique achieved better conformity and homogeneity compared to f3DCRT. In terms of OARs sparing, we found pronounced dose reductions in esophagus and heart in i3DCRT compared to f3DCRT plans. i3DCRT technique also provided a well-conformed dose distribution not superior, but comparable, to IMRT without increase in the total monitor unit per fraction (MU/fx) with respect to f3DCRT. The average monitor unit per fraction (MU/fx) for i3DCRT, f3DCRT and IMRT plans were found as 379.3, 378.0 and 1051.7 MU for the first group and 577.4, 563.5 and 1368.7 MU for the second group, respectively. Novel i3DCRT technique solves the problems associated with field junctions and beam edge matching encountered in f3DCRT plans. Additionally, i3DCRT technique can create almost similar plans as with IMRT with lower total MU/fx.
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http://dx.doi.org/10.1007/s13246-021-00976-6DOI Listing
March 2021

A hesitated approach: primary radiotherapy for keloids-a case series.

Strahlenther Onkol 2021 Jan 4. Epub 2021 Jan 4.

Department of Radiation Oncology, Hacettepe University Medical School, 06100, Ankara, Turkey.

Purpose: To assess the efficacy and toxicity of hypofractionated radiotherapy (RT) alone in treatment-resistant symptomatic keloids.

Methods: Six patients with a total of 13 inoperable large keloid lesions and no response to previous treatments were admitted to our department between 2017 and 2019. All patients were examined for detailed wound localization, size, contour, and color assessment, and for objective and subjective symptoms. Response to treatment was graded as "complete remission" in case of full symptomatic relief and >75% decrease in lesion size, as "partial remission" in case of partial symptomatic relief and 25-75% decrease in lesion size, and as "stable disease" in case of no symptomatic relief or <25% decrease in lesion size. Patients were followed up monthly for the first 3 months and every 3 months thereafter by physical examination.

Results: A total dose of 37.5 Gy external RT in five fractions was prescribed by 6‑MeV electrons in 4 patients and 6‑MV photons in 2 patients. Complete response was obtained in all patients at the 6‑month control. All patients were satisfied with cosmetic results at their last control. Grade 2 dermatitis developed in all patients during the second week of RT but resolved completely in all after 6 months following the end of RT.

Conclusion: In keloids that are unresponsive to standard treatment, hypofractionated RT using a total dose of 37.5 Gy in five fractions is feasible.
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http://dx.doi.org/10.1007/s00066-020-01736-3DOI Listing
January 2021

Single shot echo planar imaging (ssEPI) single shot turbo spin echo (ssTSE) DWI of the orbit in patients with ocular melanoma.

Br J Radiol 2021 Feb 22;94(1118):20200825. Epub 2020 Dec 22.

Department of Radiology, Hacettepe University, School of Medicine, Ankara, Turkey.

Objectives: Diffusion weighted imaging (DWI) has become important for orbital imaging. However, the echoplanar imaging (EPI) DWI has inherent obstacles due to susceptibility to magnetic field inhomogeneities. We conducted a comparative study assessing the image quality of orbits in a patient cohort with uveal melanoma (UM). We hypothesized that single shot turbo spin echo (ssTSE) DWI would have better image quality in terms of less distortion and artifacts and yield better tissue evaluation compared to ssEPI-DWI.

Methods: ssEPI-DWI and ssTSE-DWI of orbits were obtained from 50 patients with uveal melanoma who were prospectively enrolled in the study. Distortion ratio (DR), signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), diffusion signal properties, and apparent diffusion coefficient (ADC) values were collected and compared between ssEPI-DWI and ssTSE-DWI. Two reviewers evaluated and compared the geometric distortion, susceptibility and ghosting artifacts, resolution, demarcation of ocular mass, and overall quality.

Results: A higher DR was found in ssEPI-DWI compared to ssTSE-DWI ( < 0.001). SNR and CNR were lower for the temporal lobe cortex ( ≤ 0.004), but higher for melanoma in ssEPI-DWI than ssTSE-DWI ( ≤ 0.037). Geometric distortion and artifacts were more common in ssEPI-DWI ( < 0.001). Resolution ( ≤ 0.013) and overall quality ( < 0.001) were better in ssTSE-DWI. Ocular masses were demarcated better on ssEPI-DWI ( ≤ 0.002). Significant negative correlations between T1 and T2 signal intensities ( = -0.369, ≤ 0.008) and positive correlations between T2 and both DWI signal intensities ( = 0.686 and < 0.001 for ssEPI-DWI, = 0.747 and < 0.001 for ssTSE-DWI) were revealed.

Conclusion: With less geometric distortion and susceptibility artifacts, better resolution, and overall quality, ssTSE-DWI can serve as an alternative to ssEPI-DWI for orbital DWI.

Advances In Knowledge: ssTSE-DWI can be a better alternative of diffusion imaging of orbits with less susceptibility artifact and geometric distortion compared to ssEPI-DWI.
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http://dx.doi.org/10.1259/bjr.20200825DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7934310PMC
February 2021

Parotid gland stem cells: Mini yet mighty.

Head Neck 2021 Apr 27;43(4):1122-1127. Epub 2020 Nov 27.

Department of Radiation Oncology, Faculty of Medicine, Hacettepe University, Ankara, Turkey.

Background: Our aim was to evaluate the correlation between the radiation doses to parotid gland (PG) stem cells and xerostomia.

Methods: Patients diagnosed with head and neck cancer (HNC) were retrospectively evaluated, and xerostomia inventory (XI) was applied to these patients. PG stem cells were delineated on the treatment planning CT, and the mean doses to the PG stem cells calculated.

Results: The total test score and mean doses to bilateral PGs were significantly correlated (r = .34, P = .001), and the mean doses to bilateral PG stem cell niches were significantly correlated with the total test score (r = .32, P = .002).

Conclusions: In this study, we found that the mean dose to PG stem cells can predict dry mouth as much as the mean dose to the PG.
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http://dx.doi.org/10.1002/hed.26556DOI Listing
April 2021

Characterization of 3D-printed bolus produced at different printing parameters.

Med Dosim 2020 Nov 7. Epub 2020 Nov 7.

Department of Radiation Oncology, Faculty of Medicine, Hacettepe University, 06100, Ankara, Turkey.

We aimed to analyze the effects of printing parameters on characterization of three-dimensional (3D) printed bolus used in external beam radiotherapy. Two sets of measurements were performed to investigate the dosimetric and physical characterization of 3D-printed bolus at different printing parameters. In the first step, boluses were produced at different infill-percentages, infill-patterns and printing directions. Two-dimensional (2D) dose measurements were performed in Elekta Versa HD linear accelerator using 6 MV photon energy. Measured 2D dose maps for both printed and reference bolus materials were compared using the 2D gamma analysis method. Additionally, patient-specific bolus was produced with defined optimum printing parameters for anthropomorphic head and neck phantom. Then, point dose measurements were performed to evaluate the feasibility of printed bolus in clinical use. In the second step, physical measurements were carried out to evaluate the printing accuracy, the mean hounsfield unit (HU) value and the weight of 3D-printed boluses. According to our measurement, infill-percentage, infill-pattern and printing direction significantly changed the dosimetric and physical properties of the 3D-printed bolus independently. Maximum gamma passing rate at 1.5 and 5 cm depths were found as 93.8% and 98.8%, respectively, for 60% infill-percentage, sunglass fill infill-pattern and horizontal printing direction. The printing accuracy of the products was within 0.4 mm. Dosimetric and physical properties of the printed bolus material changed significantly with the selected printing parameters. Therefore, it is important to note that each combination of these printing parameters that will be used in the production of patient-specific bolus should be investigated separately.
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http://dx.doi.org/10.1016/j.meddos.2020.10.005DOI Listing
November 2020

A systematic review and practical considerations of stereotactic body radiotherapy in the treatment of head and neck cancer.

Br J Radiol 2021 Jan 24;94(1117):20200332. Epub 2020 Sep 24.

Department of Clinical Oncology, Northern Centre for Cancer Care, The Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, United Kingdom.

Objectives: Stereotactic radiotherapy (SBRT) is gaining popularity although its use in head and neck cancer (HNC) is not well defined. The primary objective was to review the published evidence regarding the use of stereotactic radiotherapy in HNC.

Methods: A literature search was performed by using MEDLINE and EMBASE databases for eligible studies from 2000 to 2019 and 26 relevant studies were identified.

Results: Literature demonstrates a heterogeneous use of this technique with regards to patient population, primary or salvage treatment, dose fractionation regimens, outcomes and follow-up protocols. Carotid blow out syndrome is a risk as with other forms of reirradiation but alternative treatment regimens may reduce this risk.

Conclusion: At present there is a lack of evidence regarding SBRT as a primary treatment option for HNC and definitive answers regarding efficacy and tolerability cannot be provided but there is growing evidence that SBRT reirradiation regimens are safe and effective. In lieu of evidence from large Phase III trials, we define appropriate organ at risk constraints and prescription doses, with accurate plan summation approaches. Prospective randomised trials are warranted to validate improved treatment outcomes and acceptable treatment morbidity.

Advances In Knowledge: This article provides a comprehensive review of evidence of use of stereotactic radiotherapy in HNC site (either as a primary treatment or as reirradiation). We also provide an evidence-based approach to the implementation and practical consideration of stereotactic radiotherapy in HNC.
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http://dx.doi.org/10.1259/bjr.20200332DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7774675PMC
January 2021

Role of Hypofractionated Stereotactic Radiosurgery in Recurrent Pineal Parenchymal Tumors of Intermediate Differentiation: A Case Report and Review of the Literature.

Cureus 2020 Aug 13;12(8):e9709. Epub 2020 Aug 13.

Radiation Oncology, Hacettepe University Medical School, Ankara, TUR.

A pineal parenchymal tumor of intermediate differentiation (PPID) is a rare entity, and optimal treatment is still unclear. Combined multimodality treatment should be considered in PPID due to high recurrence rates. Gross total resection is the first choice of treatment, however, it may not be feasible in every case due to location. Stereotactic radiosurgery (SRS) can be considered for the treatment of primary and recurrent disease, as it enables us to deliver a high radiation dose to the target while minimizing radiation exposure to normal tissue. In this report, we present a case treated with hypofractionated SRS for recurrent/metastatic PPID after the primary tumor was controlled with the combination of surgery and conventionally fractionated radiotherapy.
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http://dx.doi.org/10.7759/cureus.9709DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7489324PMC
August 2020

In Regard to Mignot et al.

Int J Radiat Oncol Biol Phys 2020 04;106(5):1109-1110

Department of Radiation Oncology, Hacettepe University Medical School, Ankara, Turkey.

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http://dx.doi.org/10.1016/j.ijrobp.2019.12.029DOI Listing
April 2020

FLASH-radiotherapy: A new perspective in immunotherapy era?

Radiother Oncol 2020 04 19;145:137. Epub 2020 Jan 19.

Hacettepe University Faculty of Medicine, Department of Radiation Oncology, Ankara, Turkey.

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http://dx.doi.org/10.1016/j.radonc.2019.12.015DOI Listing
April 2020

Comments on "Prognostic factors for survival in patients with metastatic malign melanoma treated with ipilimumab: Turkish Oncology Group study".

J Oncol Pharm Pract 2019 12 21;25(8):2060-2062. Epub 2019 Jun 21.

Faculty of Medicine, Department of Radiation Oncology, Hacettepe University, Ankara, Turkey.

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http://dx.doi.org/10.1177/1078155219858177DOI Listing
December 2019

In Regard to Bondiau et al.

Int J Radiat Oncol Biol Phys 2019 07;104(3):694

Department of Radiation Oncology, Faculty of Medicine, Hacettepe University, Ankara, Turkey.

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http://dx.doi.org/10.1016/j.ijrobp.2019.03.019DOI Listing
July 2019

Abscopal Effect, From Myth to Reality: From Radiation Oncologists' Perspective.

Cureus 2019 Jan 9;11(1):e3860. Epub 2019 Jan 9.

Radiation Oncology, Hacettepe University Medical School, Ankara, TUR.

The abscopal effect is mediated by a systemic anti-tumor immune response and reflects the regression of non-irradiated metastatic lesions at a distance from the primary site of irradiation. This review will focus on understanding the biological rationale behind the abscopal effect of radiotherapy (RT), which has a recently renewed interest as a result of the successes achieved with immunotherapy and RT in combination. Both RT and immunotherapy are standard components of modern treatment regimens. Combination of these two modalities results in an increased response in the irradiated lesions themselves and the metastatic regions distant from the site of irradiation. We will summarize the abscopal effect of radiotherapy, in particular, the synergistic effect of RT and immunotherapy.
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http://dx.doi.org/10.7759/cureus.3860DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6414182PMC
January 2019

The Synergistic Effect of Immune Checkpoint Blockade and Radiotherapy in Recurrent/Metastatic Sinonasal Cancer.

Cureus 2018 Oct 29;10(10):e3519. Epub 2018 Oct 29.

Radiation Oncology, Hacettepe University Medical School, Ankara, TUR.

Treatment options for recurrent/metastatic sinonasal cancer (RMSNC) patients are limited. We present two cases with RMSNC treated with a combination of immune checkpoint blockade and hypo-fractionated stereotactic radiotherapy (HSRT).  Case 1 presented with RMSNC three months after the primary treatment. The patient progressed under first-line chemotherapy and pembrolizumab was offered. The disease progressed after the sixth cycle. We performed reirradiation with HSRT to the primary site. Case 2 presented with local recurrence eight years after the primary treatment for maxillary sinus cancer. He refused surgery and chemotherapy and was offered nivolumab treatment. After two doses, we performed reirradiation with HSRT. Case 1 showed regression at both the local and the metastatic sites after radiotherapy. The second patient's symptoms resolved completely three months after radiotherapy. The HSRT and immune checkpoint blockade combination is a promising treatment option for patients with RMSNC.
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http://dx.doi.org/10.7759/cureus.3519DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6318133PMC
October 2018

A Novel Missense LIG4 Mutation in a Patient With a Phenotype Mimicking Behçet's Disease.

J Clin Immunol 2019 01 8;39(1):99-105. Epub 2019 Jan 8.

Department of Pediatrics, Division of Rheumatology, Hacettepe University Faculty of Medicine, 06100, Ankara, Turkey.

DNA ligase IV (LIG4) syndrome is a rare autosomal recessive disorder, manifesting with variable immune deficiency, growth failure, predisposition to malignancy, and cellular sensitivity to ionizing radiation. The facial features are subtle and variable, as well. Herein, we described an 18-year-old boy, the first child of consanguineous parents who presented with Behçet's disease (BD)-like phenotype, developmental delay, and dysembryoplastic neuroepithelial tumor (DNET). Whole-exome sequencing revealed a homozygous p.Arg871His (c.2612G > A) mutation in LIG4. To date, 35 cases have been reported with LIG4 syndrome. Peripheral blood mononuclear cells of the patient displayed notable sensitivity to ionizing radiation. Flow cytometric annexin V-propidium iodide (PI) and eFluor670 proliferation assays showed accelerated radiation-induced apoptosis and diminished proliferation, respectively. To our knowledge, this is the first case presenting with a BD-like phenotype. This case provides further evidence that rare monogenic defects could be the underlying cause of atypical presentations of some well-described disorders. Moreover, this clinical report further expands the phenotypical spectrum of LIG4 deficiency.
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http://dx.doi.org/10.1007/s10875-018-0587-7DOI Listing
January 2019

The role of ABO blood groups in glial neoplasms.

Br J Neurosurg 2019 Feb 4;33(1):43-46. Epub 2018 Nov 4.

b Radiation Oncology , Hacettepe University School of Medicine , Ankara , Turkey.

Introduction: There are numerous diseases that are claimed to have a correlation with AB0 blood groups. Analysis on distribution of blood groups in primary brain tumors and clinical value has revealed conflicting results. The purpose of this study is to evaluate the association between AB0 blood groups and glial neoplasms (GN) and their effects on prognosis.

Methods: A retrospective cross sectional study was performed. Patients admitted between 2000-2014 and had a diagnosis of GN were evaluated. Blood groups of patients were analyzed and compared with the National blood group data obtained from Turkish Red Crescent Society. The prognostic significance of AB0 blood groups was analyzed within glioblastoma multiforme (GBM), anaplastic astrocytoma and grade 1-2 astrocytoma.

Results: 759 patients with a diagnosis of glial neoplasia were evaluated. Distribution of AB0 blood groups in the different grades of Glial neoplasia was similar with the national blood group frequencies. There was not a statistically significant difference between grades of glial neoplasia and healthy control patients. Median overall survival (mOS) of GBM patients were 12.9 months in A (95% CI, 10.2-15.5), 13.4 months in B (95% CI, 7.3-19.5), 5.7 months in AB (95% CI, 0.8-10.6), 12.8 months in 0 blood groups (95% CI, 8.6-16.8) (p = .46). mOS of anaplastic astrocytoma patients were 24.4 months in A (95% CI, 15.2-33.6), 47.2 months in B (95% CI, 9.9-84.5), 37.8 months in AB (95% CI, 10.2-80.3), 29.2 months in 0 blood groups (95% CI, 21.2-33.4) (p = .96). mOS in grade 1-2 were 84.2, 90.6 and 144 months for A, AB and 0 blood groups respectively.

Conclusions: In our patient group, when compared with general population, there seems to be no association between frequencies of AB0 blood groups and Glial Neoplasia. In addition, the AB0 blood groups have no prognostic impact on glial neoplasms.
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http://dx.doi.org/10.1080/02688697.2018.1522415DOI Listing
February 2019

Comments on "High lymphocyte count during neoadjuvant chemoradiotherapy is associated with improved pathologic complete response in esophageal cancer".

Radiother Oncol 2019 02 17;131:239. Epub 2018 Oct 17.

Hacettepe University, Faculty of Medicine, Department of Radiation Oncology, Ankara, Turkey.

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http://dx.doi.org/10.1016/j.radonc.2018.10.001DOI Listing
February 2019

Fitting NTCP models to SBRT dose and carotid blowout syndrome data.

Med Phys 2018 Oct 31;45(10):4754-4762. Epub 2018 Aug 31.

Department of Radiation Oncology, Hacettepe University, Faculty of Medicine Sihhiye, Ankara, Turkey.

Purpose: To estimate the radiobiological parameters of three popular NTCP models, which describe the dose-response relations of carotid blowout syndrome (CBOS) after stereotactic body radiotherapy (SBRT). To evaluate the goodness-of-fit and the correlation of those models with CBOS.

Methods: The study included 61 patients with inoperable locally recurrent head and neck cancer treated with SBRT using CyberKnife (Accuray, Sunnyvale, CA) at the Department of Radiation Oncology, Hacettepe University, Ankara, Turkey between June 2007 and March 2011. The dose-volume histograms of the internal carotid were exported from the plans of all the patients. The follow-up results regarding the end point of carotid blowout syndrome were collected retrospectively. Initially, univariable analyses (Wilcoxon rank-sum or Chi-square tests) and a multivariate logistic regression analysis were performed between the outcome data and a list of clinical and treatment factors to identify significant correlations. Additionally, the Lyman-Kutcher-Burman (LKB), Relative Seriality (RS), and Logit NTCP models were used to fit the clinical data. The fitting of the different models was assessed through the area under the receiver operating characteristic curve (AUC), Akaike information criterion (AIC), and Odds Ratio methods.

Results: The clinical/treatment factors that were found to have a significant or close to significant correlations with acute CBOS were Age at the time of CK (P-value = 0.03), Maximum carotid dose (P-value = 0.06), and CK prescription dose (P-value = 0.08). Using D , physical DVH, and EQD -DVH as the dosimetric metrics in the NTCP models, the derived LKB model parameters were: (a) D  = 45.8 Gy, m = 0.24, n = n/a; (b) D  = 44.8 Gy, m = 0.28, n = 0.01; and (c) D  = 115.8 Gy, m = 0.45, n = 0.01, respectively. The AUC values for the dosimetric metrics were 0.70, 0.68, and 0.61, respectively. The differences in AIC between the different models were less than 2 and ranged within ±0.9.

Conclusion: The maximum dose to the internal carotid less than 34 Gy appears to significantly reduce the risk for CBOS. Age at the time of CK, Maximum carotid dose, and CK prescription dose were also found to correlate with CBOS. The values of the parameters of three NTCP models were determined for this endpoint. A threshold of gEUD <34.5 Gy appears to be significantly associated with lower risks of CBOS.
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http://dx.doi.org/10.1002/mp.13121DOI Listing
October 2018

Effectiveness of Platinum-Based Treatment for Triple Negative Metastatic Breast Cancer: a Meta-Analysis

Asian Pac J Cancer Prev 2018 May 26;19(5):1169-1173. Epub 2018 May 26.

Medstar Antalya Hospital, Department of Radiation Oncology, Antalya Education and Research Hospital, Antalya,Turkey. Email:

Background: Triple-negative breast cancer (TNBC) is a sub-group of breast cancers with a particularly poor prognosis. The results of studies investigating the role of platinum-based chemotherapy (PBC) in metastatic TNBC (mTNBC) have been conflicting. In this meta-analysis, our aim was to assess the effectiveness of PBCs for mTNBCs. Methods: The PubMed, Cochrane Controlled Trials Register Databases, and EBSCOhost databases were accessed. The English language was used as the search language and only human studies were included. The Newcastle–Ottawa Quality Assessment Scale and the Jadad scoring system were used to evaluate the quality of the included randomized controlled studies. Results: Seven studies and 1,571 patients were included in this meta-analysis. The pooled hazard ratio (HR) for overall survival (OS), evaluated on the basis of six studies, showed the use of PBC regimes to be related to OS in mTNBCs (HR 0.620; 95% CI 0.513-0.749; p:<0.001). Four studies containing HR and abstract statistics used for HR calculation were included in the meta-analysis for progression-free survival (PFS). The pooled HR again indicated a significant relation (HR, 0.628; 95% CI, 0.501-0.786; p:<0.001). Conclusions: In this meta-analysis, we confirmed that PBC regimes provide OS and PFS advantages compared to non-PBC regimes. The use of PBC regimes could be a good choice in mTNBC patients for better quality of life and survival.
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http://dx.doi.org/10.22034/APJCP.2018.19.5.1169DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6031818PMC
May 2018

Prognostic Significance of Indicators of Systemic Inflammatory Responses in Glioblastoma Patients

Asian Pac J Cancer Prev 2017 Dec 29;18(12):3287-3291. Epub 2017 Dec 29.

Medstar Antalya Hospital, Department of Radiation Oncology, Antalya, Turkey. Email:

Background: High-grade gliomas, with glioblastomas as the most frequently observed histologic subtype, are the most common primary brain tumours in adults. It is considered that inflammatory responses play a major role in malignancies, including tumour progression. This study aimed to determine the prognostic significance of the neutrophil to lymphocyte ratio (NLR) and the thrombocyte to lymphocyte ratio (PLR) as indicators of systemic inflammatory response (SIR) in glioblastoma patients. Methods: A total of 90 patients treated for glioblastoma were retrospectively evaluated. Absolute counts were used to generate NLR and PLR. A SIR was considered to be present with an NLR ≥5 and/or PLR ≥150. Results: Median follow-up time was 11.3 months (range: 1-70 months). The 1-year and 2-year overall survival rates were 55.2% and 19.5%, respectively. Univariate analysis showed that there was no correlation between overall survival and gender (p=0.184), comorbid disease (p = 0.30), clinical presentation (p = 0.884), or tumour lateralization (p = 0.159). Multivariate analysis showed that overall survival was significantly correlated with SIR based on NLR (HR: 2.41), and ECOG performance status (HR: 1.53). The prognostic factors that affected survival, other than SIR, were Eastern Cooperative Oncology Group (ECOG) performance status (p = 0.003), and tumour localization (p = 0.006). Conclusion: The present findings confirm that NLR based on peripheral blood counts prior to treatment can be used as a prognostic factor in patients with glioblastoma. Since tumour aggression increases and survival decreases as the NLR value rises, choice of treatment modality is facilitated for glioblastoma patients.
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http://dx.doi.org/10.22034/APJCP.2017.18.12.3287DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5980885PMC
December 2017

Stereotactic Radiosurgery and Fractionated Stereotactic Radiation Therapy for the Treatment of Uveal Melanoma.

Int J Radiat Oncol Biol Phys 2017 05 17;98(1):152-158. Epub 2017 Feb 17.

Department of Radiation Oncology, Faculty of Medicine, Hacettepe University, Ankara, Turkey. Electronic address:

Purpose: To evaluate treatment results of stereotactic radiosurgery or fractionated stereotactic radiation therapy (SRS/FSRT) for uveal melanoma.

Methods And Materials: We retrospectively evaluated 181 patients with 182 uveal melanomas receiving SRS/FSRT between 2007 and 2013. Treatment was administered with CyberKnife.

Results: According to Collaborative Ocular Melanoma Study criteria, tumor size was small in 1%, medium in 49.5%, and large in 49.5% of the patients. Seventy-one tumors received <45 Gy, and 111 received ≥45 Gy. Median follow-up time was 24 months. Complete and partial response was observed in 8 and 104 eyes, respectively. The rate of 5-year overall survival was 98%, disease-free survival 57%, local recurrence-free survival 73%, distant metastasis-free survival 69%, and enucleation-free survival 73%. There was a significant correlation between tumor size and disease-free survival, SRS/FSRT dose and enucleation-free survival; and both were prognostic for local recurrence-free survival. Enucleation was performed in 41 eyes owing to progression in 26 and complications in 11.

Conclusions: The radiation therapy dose is of great importance for local control and eye retention; the best treatment outcome was achieved using ≥45 Gy in 3 fractions.
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http://dx.doi.org/10.1016/j.ijrobp.2017.02.017DOI Listing
May 2017

The effect of glutamine and arginine-enriched nutritional support on quality of life in head and neck cancer patients treated with IMRT.

Clin Nutr ESPEN 2016 Dec 13;16:30-35. Epub 2016 Sep 13.

Hacettepe University, Faculty of Medicine, Department of Radiation Oncology, Ankara, Turkey.

Background And Aims: Oral mucositis and esophagitis are common acute toxicities of radiotherapy (RT) for head and neck cancer (HNC). In order to decrease the rates of these toxicities, we compared quality of life in HNC patients that did and did not receive a glutamine and arginine-enriched solution (GAES) during RT.

Methods: A total of 29 patients received intensity-modulated radiotherapy (IMRT); 15 used GAES b.i.d. during the treatment, and a matched cohort of 14 patients did not. Patients were administered the EORTC QLQ-C30, QLQ-H&N35 and QLQ-OES18 questionnaires on the 1st, 15th, and last days of IMRT.

Results: The global health status, functional and symptom scale scores were similar in both groups on the 1st day of IMRT. On the 15th and last days, the scores of social functions (p = 0.01 and p = 0.012), pain (p = 0.002 and p = 0.002), appetite (p = 0.01 and p = 0.02), dry mouth (p = 0.001 and p = 0.03), sticky saliva (p = 0.003 and p = 0.04), trouble with taste (p = 0.001 and p = 0.03), trouble with social eating (p = 0.004 and p = 0.006), and swallowing problems (p = 0.002 and p = 0.046) were significantly worse in the control group.

Conclusions: Quality of life is negatively affected by IMRT; however, use of GAES may mediate this negative effect.
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http://dx.doi.org/10.1016/j.clnesp.2016.08.003DOI Listing
December 2016

In Regard to Chadha et al.

Int J Radiat Oncol Biol Phys 2017 06;98(2):484-485

Department of Radiation Oncology, Hacettepe University Medical School, Ankara, Turkey.

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http://dx.doi.org/10.1016/j.ijrobp.2017.02.025DOI Listing
June 2017

Reirradiation of Pediatric Tumors Using Hypofractionated Stereotactic Radiotherapy.

Technol Cancer Res Treat 2017 04 8;16(2):195-202. Epub 2016 Jul 8.

1 Department of Radiation Oncology, School of Medicine, Hacettepe University, Ankara, Turkey.

Background: This study aimed to evaluate the efficacy and safety of hypofractionated stereotactic radiotherapy for reirradiation of recurrent pediatric tumors.

Methods And Materials: The study included 23 pediatric patients who were reirradiated using hypofractionated stereotactic radiotherapy in the radiation oncology department between January 2008 and November 2013. In total, 33 tumors were treated-27 (82%) cranial and 6 (18%) extracranial. Hypofractionated stereotactic radiotherapy was administered due to recurrent disease in 31 (94%) tumors and residual disease in 2 (6%) tumors. The median total dose was 25 Gy (range: 15-40 Gy), and the median follow-up was 20 months (range: 2-68 months).

Results: The 1-year and 2-year local control rates in the entire study population were 42% and 31%, respectively. The median local control time was 11 months (range: 0-54 months) following hypofractionated stereotactic radiotherapy. The patients with tumor response after hypofractionated stereotactic radiotherapy had significantly longer local control than the patients with post-hypofractionated stereotactic radiotherapy tumor progression (21 vs 3 months, P < .001). Tumor volume <1.58 cm was correlated (not significantly) with better local control (23 vs 7 months, P = .064).

Conclusion: Reirradiation of pediatric tumors using hypofractionated stereotactic radiotherapy is a safe and effective therapeutic approach. This treatment modality should be considered as a treatment option in selected pediatric patients.
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http://dx.doi.org/10.1177/1533034616655952DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5616030PMC
April 2017

The dosimetric impact of implants on the spinal cord dose during stereotactic body radiotherapy.

Radiat Oncol 2016 May 25;11:71. Epub 2016 May 25.

Department of Radiation Oncology, Hacettepe University, Faculty of Medicine, Ankara, Turkey.

Background: The effects of spinal implants on dose distribution have been studied for conformal treatment plans. However, the dosimetric impact of spinal implants in stereotactic body radiotherapy (SBRT) treatments has not been studied in spatial orientation. In this study we evaluated the effect of spinal implants placed in sawbone vertebra models implanted as in vivo instrumentations.

Methods: Four different spinal implant reconstruction techniques were performed using the standard sawbone lumbar vertebrae model; 1. L2-L4 posterior instrumentation without anterior column reconstruction (PI); 2. L2-L4 anterior instrumentation, L3 corpectomy, and anterior column reconstruction with a titanium cage (AIAC); 3. L2-L4 posterior instrumentation, L3 corpectomy, and anterior column reconstruction with a titanium cage (PIAC); 4. L2-L4 anterior instrumentation, L3 corpectomy, and anterior column reconstruction with chest tubes filled with bone cement (AIABc). The target was defined as the spinous process and lamina of the lumbar (L) 3 vertebra. A thermoluminescent dosimeter (TLD, LiF:Mg,Ti) was located on the measurement point anterior to the spinal cord. The prescription dose was 8 Gy and the treatment was administered in a single fraction using a CyberKnife® (Accuray Inc., Sunnyvale, CA, USA). We performed two different treatment plans. In Plan A beam interaction with the rod was not limited. In plan B the rod was considered a structure of avoidance, and interaction between the rod and beam was prevented. TLD measurements were compared with the point dose calculated by the treatment planning system (TPS).

Results And Discussion: In plan A, the difference between TLD measurement and the dose calculated by the TPS was 1.7 %, 2.8 %, and 2.7 % for the sawbone with no implant, PI, and PIAC models, respectively. For the AIAC model the TLD dose was 13.8 % higher than the TPS dose; the difference was 18.6 % for the AIABc model. In plan B for the AIAC and AIABc models, TLD measurement was 2.5 % and 0.9 % higher than the dose calculated by the TPS, respectively.

Conclusions: Spinal implants may be present in the treatment field in patients scheduled to undergo SBRT. For the types of implants studied herein anterior rod instrumentation resulted in an increase in the spinal cord dose, whereas use of a titanium cage had a minimal effect on dose distribution. While planning SBRT in patients with spinal reconstructions, avoidance of the rod and preventing interaction between the rod and beam might be the optimal solution for preventing unexpectedly high spinal cord doses.
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http://dx.doi.org/10.1186/s13014-016-0649-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4880816PMC
May 2016

High-grade glioma in children and adolescents: a single-center experience.

Childs Nerv Syst 2016 Feb 17;32(2):291-7. Epub 2015 Dec 17.

Department of Radiation Oncology, School of Medicine, Hacettepe University, Sihhiye, 06100, Ankara, Turkey.

Purpose: The aim of this study was to report the outcome in children with high-grade astrocytoma outside the brain stem and spinal cord that were treated at a single center.

Materials And Methods: The study included 26 patients with anaplastic astrocytoma and 37 patients with glioblastoma; all patients were aged ≤18 years. At initial diagnosis, 18 of the patients with glioblastoma received only temozolomide (TMZ), 14 received other chemotherapies, and 5 did not receive any chemotherapy. Among the patients with anaplastic astrocytoma, 9 received TMZ, 9 received other chemotherapy regimens, and 8 patients did not receive any chemotherapy. The median radiotherapy dose in all patients was 60 Gy.

Results: Median age of the patients was 12.5 years. Median overall survival was 20 months and mean progression-free survival was 4.7-11.3 months (median: 8 months) in all patients. Patients with a Karnofsky performance score (KPS) ≥70 had median overall survival of 32 months, versus 7 months in those with a KPS < 70. Patients aged <15 years had median survival of 38 months, versus 16 months in those aged 15-18 years. Patients with anaplastic astrocytoma that received TMZ, other chemotherapy regimens, and no chemotherapy had median survival of 21 months, 132 months, and 11 months, respectively. Patients with glioblastoma that received TMZ, other chemotherapy regimens, and no chemotherapy had median survival of 32 months, 12 months, and 8 months, respectively.

Conclusion: In the present study, patients with anaplastic astrocytoma treated with chemotherapy protocols other than TMZ had the longest OS; however, in the glioblastoma group, OS was 32 months in those treated with standard TMZ and 12 months in those treated with other protocols (P = 0.493). Although TMZ is less toxic than PCV, it was not shown to be superior.
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http://dx.doi.org/10.1007/s00381-015-2980-3DOI Listing
February 2016

Comparison of three different induction regimens for nasopharyngeal cancer.

Asian Pac J Cancer Prev 2015 ;16(1):59-63

Department of Medical Oncology, Faculty of Medicine, Hacettepe University, Ankara, Turkey E-mail :

Background: The standard treatment of local advanced nasopharyngeal cancer is chemoradiotherapy. There is a lack of data concerning induction therapy. In this study we retrospectively examined patients treated with induction therapy and chemoradiotherapy.

Materials And Methods: Locally advanced nasopharyngeal cancer patients treated between 1996 and 2013 in our clinic were included in the study. Three different induction regimens were administered to our patients in different time periods. The regimen dosages were: CF regimen, cisplatin 50mg/m2 1-2 days, fluorouracil 500mg/m2 1-5 days; DC, docetaxel 75mg/m2 1 day, cisplatin 75mg/m2 1 day; and DCF, docetaxel 75mg/m2 1 day, cisplatin 75mg/m2 1 day, 5-Fu 750mg/m2 1-5 days. Most of the patients were stage III (36.4%) and stage IV (51.7%).

Results: Median follow-up time was 50 months (2-201 months). Three-year progression-free survival (PFS) was 79.3%, and 5-year PFS 72.4% in all patients. Three-year overall survival (OS) was 87.4% and 5-year OS 76% in all patients. In terms of induction therapies, 3-year OS was 96.5% in the DCF group, 86.6% in the DC group and 76.3% in the CF group (p=0.03).

Conclusions: There was no significant differences in response rate and PFS between the three regimens. OS in the DCF group was significantly higher than in the other groups. However, this study was retrospective and limited toxicity data were available; the findings therefore need to be interpreted with care.
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http://dx.doi.org/10.7314/apjcp.2015.16.1.59DOI Listing
October 2015