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Item Prostate Mucinous Carcinoma Treated with Definitive Radiotherapy and Hormonal Therapy: Case Report and Review of the Literature(2014) Guler, Ozan Cem; Onal, Cem; Erbay, Gurcan; https://orcid.org/0000-0001-6908-3412; https://orcid.org/0000-0002-2742-9021; https://orcid.org/0000-0002-1706-8680; 24365124; AAC-5654-2020; HOC-5611-2023; AAK-5370-2021Prostate mucinous carcinoma (MC) is a rare variant of prostate adenocarcinoma that is characterized by large pools of extracellular mucin, which by definition compose at least 25% of the tumor volume. Prostate MC has 3 subtypes. The most common variant is pure MC; primary signet ring cell carcinoma and MC with signet ring cell are less common variants and are more aggressive than pure MC. Because of the rarity of prostate MC and conflicting reports regarding the behavior of the disease, the optimal treatment strategy is not clear. Most series report the efficacy of surgery. We report a rare case of a patient with a large prostate MC that was treated successfully with hormone therapy (HT) and radiotherapy (RT). Treatment response was assessed by dynamic contrast-enhanced magnetic resonance imaging (MRI). (C) 2014 Elsevier Inc. All rights reserved.Item Treatment Outcomes of Patients with Cervical Cancer with Complete Metabolic Responses After Definitive Chemoradiotherapy(2014) Onal, Cem; Reyhan, Mehmet; Guler, Ozan C.; Yapar, Ali Fuat; https://orcid.org/0000-0002-2742-9021; https://orcid.org/0000-0001-8550-3368; https://orcid.org/0000-0001-6908-3412; https://orcid.org/0000-0003-1715-4180; 24562649; HOC-5611-2023; AAJ-5242-2021; AAC-5654-2020; AAI-8973-2021Purpose We sought to evaluate failure patterns and prognostic factors predictive of recurrences and survival in cervical cancer patients who are treated with definitive chemoradiotherapy (ChRT), who have a subsequent complete metabolic response (CMR) with (18) F-fluorodeoxyglucose positron-emission tomography (FDG-PET) after treatment. Methods The records of 152 cervical cancer patients who were treated with definitive chemoradiotherapy were evaluated. All patients underwent pre-treatment positron emission tomography (PET-CT), and post-treatment PET-CT was performed within a median of 3.9 months (range, 3.0-9.8 months) after the completion of ChRT. The prognoses of partial response/progressive disease (PR/PD) cases (30 patients, 18 %) and CMR cases (122 patients, %82) were evaluated. Univariate and multivariate analysis effecting the treatment outcome was performed in CMR cases. Results The median follow-ups for all patients and surviving patients were 28.7 (range, 3.3-78.7 months) and 33.2 months (range, 6.23-78.7 months), respectively. Four-year overall survival (OS) rate was significantly better in patients with CMR compared to patients with PR/PD (66.9 % vs. 12.4 %, p < 0.001, respectively). Patients with PR/PD had higher maximum standardized uptake value (SUVmax) of primary cervical tumor (26.4 +/- 10.1 vs. 15.9 +/- 6.3; p < 0.001) and larger tumor (6.4 cm +/- 2.3 cm vs. 5.0 cm +/- 1.4 cm; p < 0.001) compared to patients with CMR. Of the 122 patients with post-treatment CMRs, 25 (21 %) developed local, locoregional, or distant failure. In univariate analysis, tumor size a parts per thousand yen 5 cm, 'International Federation of Obstetricians and Gynecologists' (FIGO) stage a parts per thousand yenaEuro parts per thousand IIB, and pelvic and/or para-aortic lymph node metastasis were predictive of both overall survival (OS) and disease-free survival (DFS), while histology was predictive of only OS. In multivariate analysis, tumor size, stage and lymph node metastasis were predictive of OS and DFS. Conclusion Although CMR is associated with better outcomes, relapses remain problematic, especially in patients with bulky tumors (a parts per thousand yen 5 cm), extensive stage (a parts per thousand yen IIB) or pelvic and/or para-aortic lymph node metastasis. These findings could support the need for more aggressive treatment or adjuvant chemotherapy regimens.Item Multifocal Soft Tissue Langerhans' Cell Histiocytosis Treated with PET-CT Based Conformal Radiotherapy(2015) Onal, Cem; Oymak, Ezgi; Reyhan, Mehmet; Canpolat, Tuba; Ozyilkan, Ozgur; 0000-0002-2742-9021; 0000-0001-8550-3368; 0000-0001-8825-4918; 26211006; AGG-9214-2022; HOC-5611-2023; D-5195-2014; AAJ-5242-2021; AAD-2817-2021; AAK-8107-2021Langerhans' cell histiocytosis (LCH) is a proliferative disorder of Langerhans cells, which is seen extremely rarely in adults. Conventional imaging modalities, such as skeletal surveys and bone scans, were accepted to be standard methods for diagnosis; however, 18-fluorodeoxyglucose positron emission tomography (PET-CT) has been increasingly used. We report on a 33-year-old female patient with disseminated LCH treated with radiotherapy and systemic chemotherapy where PET-CT has been used for defining the extent of the disease, RT planning and assessment of treatment response during follow-up. The patient was treated with 24 Gy 3-dimensional conformal radiotherapy (RT), given as 2 Gy a day, 5 days a week. The patient was also treated with systemic prednisolone 20 mg/m(2), concurrently. The chemotherapeutic regimen switched to cytosine-arabinoside with a dose of 100 mg/m(2) subcutaneously daily for 4 days, vincristine 1.5 mg/m(2) given on the 1st day and prednisolone 20 mg/m(2) for 4 cycles. After local RT with adjuvant chemotherapy, the patient was alive for 54 months and remained disease-free at last visit. RT is a treatment choice in multi-system LCH as well as solitary lesions. Low-dose RT is adequate to control large masses of LCH including soft tissue and lymph nodes.Item Assessing the Quality of Life in Patients with Endometrial Cancer Treated with Adjuvant Radiotherapy(2015) Karabuga, Havva; Gultekin, Melis; Tulunay, Gokhan; Yuce, Kunter; Ayhan, Ali; Yuce, Deniz; Yildiz, Ferah; 0000-0003-0440-0725; 26207785; AAJ-5802-2021Objective The current study evaluates long-term quality of life (QOL) and sexual function of patients with endometrial cancer who received adjuvant pelvic external beam radiotherapy (EBRT) and/or vaginal brachytherapy (BRT). Materials and Methods One hundred forty-four endometrial cancer survivors who were treated between January 2000 and December 2009 in our department were included in this study. Median follow-up was 79 months (range, 31-138 months). Fifty-two patients were treated with 45 to 50.4 Gy EBRT, 76 were with BRT, and 16 were with both EBRT and BRT. Brachytherapy was in the form of vaginal cuff BRT with 5 x 550 cGy high dose rate BRT, prescribed to the first 4 cm and whole wall thickness of vagina. Quality of life was assessed using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 and subscales from the supplemental 24-item Cervical Cancer Module. Results Vaginal BRT patients reported better physical functioning (P = 0.01), role functioning (P = 0.03), and sexual enjoyment (P = 0.01) compared to EBRT group. Symptom score (P = 0.01), lymphedema (P = 0.03), pain (P = 0.02), and diarrhea (P = 0.009) scores were also higher with EBRT. Vaginal BRT did not worsen symptom scores or sexual functions when added to EBRT. Obese patients experienced higher rates of lymphedema (P = 0.008). Cognitive and role functioning scores were significantly higher in patients with normal body mass index. Conclusions External beam radiotherapy negatively affects long-term QOL and sexual functions in endometrial cancer survivors. Vaginal BRT provides higher QOL. Patients with body mass index within normal limits have improved QOL.Item Effective Resolution of Lung Cancer Related Tracheal and/or Bronchial Obstruction with External Beam Radiotherapy(2015) Topkan, Erkan; Yildirim, Berna Akkus; Ozdemir, Yurday; Guler, Ozan C.; Kose, Fatih; 0000-0001-6908-3412; 0000-0001-8120-7123; 0000-0002-2218-2074; 0000-0001-6661-4185; AAC-5654-2020; AAG-2213-2021; AAG-5629-2021; V-5717-2017Item Daily Workflow and Workload of Radiation Oncology Specialists in Turkey(2015) Akman, Fadime; Kamer, Serra; Onal, Cem; Agaoglu, Fulya; Guney, Yildiz; Hicsonmez, Ayse; Koc, Mehmet; Colpan Oksuz, Didem; Ozyigit, Gokhan; Ozkok, Serdar; 0000-0002-2742-9021; D-5195-2014OBJECTIVES This study aimed to research the effort required by patient evaluation, radiotherapy planning and treatment processes in the daily applications of radiation oncology in terms of time, and to use this effort as the primary source for human power and infrastructure planning required in radiotherapy. METHODS The surveys carried out by Turkish Radiation Oncology Association Proficiency Board, Curriculum Preparation and Evaluation Commission on Education Institutions, Surveys delivered to the officers of the center via electronic mail, were answered and evaluated in accordance with the data of 2012. RESULTS 26 University and 8 Ministry of Health Hospitals participated in the study. The total number of specialists employed in the participant centers, were 227. For per specialist, 383 hours in a year were spent for the patients at follow-up, 334 hours were spent for the patients that were in treatment, and 950 hours were spent for planning and treatment set-ups. It was determined that the time spent for per patient in intensity modulated radiotherapy technique, was 2-3 times more when compared to the location of tumor, which is a conformal technique. It was observed that this duration was much longer in special radiotherapy applications such as brachytherapy, total body irradiation and radiosurgery. CONCLUSION Technological advancements in radiotherapy, require more effort and working time for new job descriptions and in daily practice.Item Stereotactic Ablative Body Radiotherapy as a Bridge to Liver Transplant for Hepatocellular Carcinoma: Preliminary Results of Baskent University Experience(2022) Yavas, Guler; Soy, Ebru Hatice Ayvazoglu; Coskun, Mehmet; Onal, Cem; Boyvat, Fatih; Haberal, Mehmet; https://orcid.org/0000-0002-3462-7632; 35384806; HOC-5611-2023; AAJ-8097-2021Objectives: Hepatocellular carcinoma is the most common primary liver tumor, with curative treatment options being liver transplant and resection. However, approximately 20% to 30% of patients have substantial disease progression while awaiting transplant. Here, we report our initial experience on stereotactic ablative body radiotherapy as a bridge to liver transplant for patients with hepatocellular carcinoma. Materials and Methods: Seven patients with 9 lesions received stereotactic ablative body radiotherapy as a bridge treatment to transplant. All patients underwent radiofrequency ablation, transcatheter arterial chemoembolization, or hepatic resection before stereotactic ablative body radiotherapy. Magnetic resonance imaging was used to evaluate radiographic responses 1 month later. Results: Median age of patients was 65 years (range, 63-71 years), median stereotactic ablative body radiotherapy dose was 45 Gy (range, 30-54 Gy; delivered in 3-5 fractions), and median tumor diameter was 17 mm (range, 12-30 mm). Before stereotactic ablative body radiotherapy, all patients underwent liver-directed therapies, including transcatheter arterial chemoembolization for 3 lesions, transcatheter arterial chemoembolization and radiofrequency ablation for 4 lesions, surgical resection for 1 lesion, and surgical resection plus transcatheter arterial chemoembolization for the remaining lesion. Patients showed no evidence of gastrointestinal toxicity or radiation-induced liver disease. Acute toxicity was negligible; all patients completed the treatment course. One month after stereotactic ablative body radiotherapy administration, response rates were assessed with magnetic resonance imaging, with complete responses obtained in 5 lesions (55.5%), partial responses for 2 lesions, and stable disease for 2 lesions. No disease progression was shown following stereotactic ablative body radiotherapy application. Conclusions: Stereotactic ablative body radiotherapy is an effective, safe, and tolerable bridging therapy option. Although we observed an early response after treatment, exact response rates will not be known for at least 3 months following stereotactic ablative body radiotherapy. Thus, our findings should be confirmed through additional prospective studies with longer follow-up.Item How Does Radiotherapy Affect the Adhesion of Universal Adhesive to Enamel and Dentin? A Qualitative and Quantitative Analysis?(2022) Oglakci, Burcu; Burduroglu, Defne; Eri, Ali Hikmet; Mayadagli, Alpaslan; Arhun, NeslihanThis study investigated the shear bond strength (SBS) of a universal adhesive to enamel/dentin; 1) that had undergone radiotherapy (RT) and 2) that were readily restored and had undergone RT. Enamel and dentin surfaces were obtained from 90 intact human molars. They were randomly divided into six groups according to the presence and timing of irradiation (RTO:no radiotherapy/control, RT1:RT before restoration, RT2:RT after restoration groups) and adhesive application modes (etch&rinse/ER, self-etch/SE)(n=15). A universal adhesive and resin composites were applied. The radiotherapy protocol was conducted with 60 Gy. The SBS test was subjected (1mm/min) and failure type analysis was performed. The resin-enamel/ dentin interfaces were examined. Data were statistically analyzed. For enamel and dentin, the presence and timing of irradiation did not significantly influence the SBS values (p>0.05). For enamel, significantly higher SBS values were obtained using etch&rinse mode than self-etch mode (p<0.05). The predominant failure was mixed type. Loss of enamel prisms and obliterated irregular dentinal tubules were found for the radiotherapy-treated specimens. Resin tags were clearer in the irradiated enamel treated with ER than SE. Irradiation with different timings did not influence the bond strength to enamel and dentin, negatively. Irrespective of radiotherapy, the etch&rinse mode caused higher bond strength to enamel than self-etch mode.Item The Feasibility of Prostate-Specific Membrane Antigen Positron Emission Tomography(PSMA PET/CT)-Guided Radiotherapy in Oligometastatic Prostate Cancer Patients(2018) Guler, O. C.; Engels, B.; Onal, C.; Everaert, H.; Van den Begin, R.; Gevaert, T.; de Ridder, M.; https://orcid.org/0000-0001-6908-3412; https://orcid.org/0000-0001-9108-610X; https://orcid.org/0000-0002-2742-9021; https://orcid.org/0000-0003-3633-6203; https://orcid.org/0000-0003-4556-5681; https://orcid.org/0000-0003-4433-8807; 28795303; AAC-5654-2020; HOC-5611-2023; B-1285-2018; F-3248-2016; F-4794-2013To investigate the efficacy and toxicity of 68Ga-PSMA-HBED-CC (Ga-68-PSMA) PET-CT-guided RT in the treatment of oligometastatic prostate cancer retrospectively. A total of 23 prostate cancer patients with biochemical relapse, of which 13 were castration sensitive (CS) and 10 castration resistant (CR), were treated with intensity-modulated and image-guided RT (IMRT-IGRT) on 3 metastases detected by Ga-68 PSMA PET-CT. Androgen deprivation therapy was continued in CR patients. A total of 38 metastases were treated. The involved sites were pelvic bone (n = 16), pelvic lymph nodes (n = 11), paraaortic lymph nodes (n = 6), ribs (n = 3) and vertebral body (n = 2). The median PSA prior to RT was 1.1 ng/mL (range 0.1-29.0 ng/mL). A median dose of 43.5 Gy (range 30-64 Gy) was delivered by IMRT-IGRT in 12-27 fractions. At a median follow-up of 7 months (range 2-17 months), 19 patients (83%) were in remission. Four patients (17%) developed distant recurrences. The actuarial 1-year LC, PFS and OS rates were 100, 51 (95% CI 8-83%) and 100%. Univariate analysis demonstrated a statistically significantly better PFS in CS patients as compared to CR patients (1-year PFS 67 vs. 0%, p < 0.01). One patient experienced grade 2 acute gastrointestinal toxicity. Grade 3 or more toxicity events were not observed. By providing optimal LC, low toxicity and a promising PFS in CS patients, the current retrospective study illustrated that Ga-68 PSMA PET-CT-guided RT may be an attractive treatment strategy in patients with oligometastatic prostate cancer. Validation by randomized trials is eagerly awaited.Item Treatment Outcomes of Breast Cancer Liver Metastasis Treated with Stereotactic Body Radiotherapy(2018) Onal, Cem; Guler, Ozan Cem; Yildirim, Berna Akkus; https://orcid.org/0000-0002-2742-9021; https://orcid.org/0000-0001-6908-3412; https://orcid.org/0000-0001-6661-4185; 30296648; HOC-5611-2023; AAC-5654-2020; V-5717-2017Background: To assess the outcomes of breast cancer liver metastasis (BCLM) treated with stereotactic body radiotherapy (SBRT) and systemic treatment. Materials and methods: Patients with oligometastasis at the time of liver metastasis (LM) or who became oligometastatic (<= 5 metastases) after systemic treatment were assessed. Twenty-nine liver metastatic lesions were treated with a total of 54 Gy delivered in 3 fractions. The local control (LC), overall survival (OS), and progression-free survival (PFS) rates were calculated using Kaplan-Meier analyses. Results: A total of 22 patients with 29 liver metastatic lesions treated with liver SBRT between April 2013 and September 2017 were retrospectively analyzed. After a median follow-up time of 16.0 months (range 4.4-59.4 months), 18 patients (82%) had disease recurrence, median of 7.4 months (range 1.0-27.9 months) after completion of liver SBRT. The 1- and 2-year OS rates were 85% and 57%, and the 1- and 2-year PFS rates were 38% and 8%, respectively. The 1- and 2-year LC rates were 100% and 88%, respectively. No significant prognostic factors, including disease extension, size of metastasis, number of liver metastasis and timing of liver metastasis, hormonal status affecting OS, PFS and LC were found. No patients experienced Grade 4 or 5 toxicity; furthermore, only one patient experienced rib fracture 6 months after completion of treatment, and one patient had a duodenal ulcer. Conclusion: This study is the first to evaluate the feasibility of SBRT to BCLM patients. Liver SBRT is a conservative approach with excellent LC and limited toxicities. (C) 2018 Elsevier Ltd. All rights reserved.