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Öğe Brain metastases from prostate cancer: A single-center experience(Aves, 2019) Kanyilmaz, Gul; Aktan, Meryem; Yavuz, Berrin Benli; Koc, MehmetObjective: Metastases from prostate cancer to the brain are very unusual and very few case series have been reported in the literature. Present study was performed to assess the proportion of brain metastasis from prostate cancer among other brain metastasis in men, to evaluate the distribution, pattern and magnetic resonance imaging (MRI) appearance of these metastatic lesions, and prognosis of brain metastasis in patients with prostate cancer. Material and methods: Between January 2010 and November 2016, 339 males who had received radiotherapy at our department were retrospectively reviewed. After the first evaluation of patients data, we reviewed only the patients with brain metastases from prostate cancer. We evaluated MRI characteristics of metastatic brain lesions and characteristics of the patients, tumor and treatment modalities. Results: Ten of 339 patients (2.9%) had brain metastases from prostate cancer. Sixty percent of the patients had pure intraparenchymal metastasis, 20% of the patients had pure extensive dural metastasis and 20% of them had both. Seventy-five percent of the patients with intraparenchymal metastasis had multiple metastatic lesions. The median prostate specific antigen (PSA) level was 49.40 ng/mL and the Gleason score was >= 7 in all patients. Sixty percent of the patients had distant metastasis at the time of the diagnosis of prostate cancer. Median survival time in patients with brain metastasis was 4.5 months. Conclusion: Lesions of brain metastasis from prostate cancer had a large variety of imaging presentation and it is very difficult to distinguish them from the other brain metastasis originating from other types of cancer. Presence of a disseminated disease, high PSA level and high Gleason score can be useful parameters for the prediction of brain metastasis from prostate cancer.Öğe Cancer among syrian refugees living in Konya Province, Turkey(Bmc, 2022) Kutluk, Tezer; Koc, Mehmet; Oner, Irem; Babalioglu, Ibrahim; Kirazli, Meral; Aydin, Sinem; Ahmed, FahadBackground With more than 3.6 million Syrian refugees Turkey hosts the world's largest number of Syrians. Considering the morbidity, mortality, and healthcare spending, cancer is one of the leading health and economic burden for patients and healthcare systems. However, very limited information available in the scientific literature to understand the burden and characteristics of cancer in countries hosting Syrian refugees. The aim of the present study is to evaluate the demographic and clinical characteristics, treatment outcome of Syrian cancer patients living in Konya, Turkey. Methods We retrospectively reviewed medical records of Syrian cancer patients at three major institutions from 2005 to 2020. The information regarding demographic and clinical characteristics of patients were identified. The number of days between the first symptom and diagnosis was considered as the diagnostic interval. Patients who failed to attend clinics within four weeks of appointment were assumed abandoned treatment. Survival curves were estimated using the Kaplan-Meier method. Results We identified 230 adult and 38 children refugee diagnosed with cancer during the study period. With regards to adult patients, there were 114 (49.6%) male and 116 (50.4%) female. The median age at diagnosis was 52.4, 47.3 years for male, female respectively. The five most common cancer by site among all were; breast (24.8%), colorectal (10.9%), lung (7.4%), central nervous system (CNS) (7.0%), and stomach (5.2%). 93 (40.4%) had metastatic disease at diagnosis. The overall survival probability was 37.5% at five years for the adult population. Data were extracted for 20 boys and 18 girls with childhood cancer. Their median age at diagnosis was 5.8 and 6.0 years respectively. The three most common childhood cancer were; leukemias (21.1%), lymphomas (21.1%), and CNS (13.2%). Excluding leukemia, 13 (43.3%) of childhood cancer cases had the advanced disease at diagnosis. Three year survival probality was 69.5%. The median diagnostic interval for adult and childhood cancer was 96.5 (IQR = 53-165) and 23 (IQR = 13.5-59) days respectively. Twenty-one adults and four children had treatment abandonment. Conclusion This study contributes to understanding the burden of cancer among Syrian refugees living in Konya, growing health issue for refugees. Larger and prospective studies will help to measure the real burden and compare the difference in cancer risk factors, care, and outcomes among the refugee and host populations.Öğe Cancer among syrian refugees living in Konya Province, Turkey(Bmc, 2022) Kutluk, Tezer; Koc, Mehmet; Oner, Irem; Babalioglu, Ibrahim; Kirazli, Meral; Aydin, Sinem; Ahmed, FahadBackground With more than 3.6 million Syrian refugees Turkey hosts the world's largest number of Syrians. Considering the morbidity, mortality, and healthcare spending, cancer is one of the leading health and economic burden for patients and healthcare systems. However, very limited information available in the scientific literature to understand the burden and characteristics of cancer in countries hosting Syrian refugees. The aim of the present study is to evaluate the demographic and clinical characteristics, treatment outcome of Syrian cancer patients living in Konya, Turkey. Methods We retrospectively reviewed medical records of Syrian cancer patients at three major institutions from 2005 to 2020. The information regarding demographic and clinical characteristics of patients were identified. The number of days between the first symptom and diagnosis was considered as the diagnostic interval. Patients who failed to attend clinics within four weeks of appointment were assumed abandoned treatment. Survival curves were estimated using the Kaplan-Meier method. Results We identified 230 adult and 38 children refugee diagnosed with cancer during the study period. With regards to adult patients, there were 114 (49.6%) male and 116 (50.4%) female. The median age at diagnosis was 52.4, 47.3 years for male, female respectively. The five most common cancer by site among all were; breast (24.8%), colorectal (10.9%), lung (7.4%), central nervous system (CNS) (7.0%), and stomach (5.2%). 93 (40.4%) had metastatic disease at diagnosis. The overall survival probability was 37.5% at five years for the adult population. Data were extracted for 20 boys and 18 girls with childhood cancer. Their median age at diagnosis was 5.8 and 6.0 years respectively. The three most common childhood cancer were; leukemias (21.1%), lymphomas (21.1%), and CNS (13.2%). Excluding leukemia, 13 (43.3%) of childhood cancer cases had the advanced disease at diagnosis. Three year survival probality was 69.5%. The median diagnostic interval for adult and childhood cancer was 96.5 (IQR = 53-165) and 23 (IQR = 13.5-59) days respectively. Twenty-one adults and four children had treatment abandonment. Conclusion This study contributes to understanding the burden of cancer among Syrian refugees living in Konya, growing health issue for refugees. Larger and prospective studies will help to measure the real burden and compare the difference in cancer risk factors, care, and outcomes among the refugee and host populations.Öğe Cutaneous Metastases of the Synchronous Primary Endometrial and Bilateral Ovarian Cancer: An Infrequent Presentation and Literature Review(Hindawi Ltd, 2016) Kanyilmaz, Gul; Aktan, Meryem; Koc, Mehmet; Findik, SiddikaThere are limited data about the cutaneous metastases of gynecological malignancies in the literature. Based on this limited number of studies, cutaneous metastases from gynecological malignancies are uncommon occurrences. Cutaneous metastases from the synchronous endometrioid carcinoma of the uterine corpus and bilateral ovaries arising from endometriosis are extremely rare. Herein, we report a 51-year-old woman with FIGO Stage 1A Grade 1 endometrial endometrioid-type adenocarcinoma and synchronous bilateral Stage 1B ovarian endometrioid-type adenocarcinoma who presented 34 months following total abdominal hysterectomy and bilateral salpingo-oophorectomy with skin metastases. After the patient underwent an excisional biopsy, we applied a palliative radiotherapy. The patient received the combination therapy with cisplatin and doxorubicin after the completion of radiotherapy but the disease evolution was rapidly fatal and the patient died 4 months after her admission to our department due to widely disseminated disease.Öğe Daily workflow and workload of radiation oncology specialists in Turkey(Kare Publ, 2015) Akman, Fadime; Kamer, Serra; Onal, Cem; Agaoglu, Fulya; Guney, Yildiz; Hicsonmez, Ayse; Koc, MehmetOBJECTIVES 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.Öğe Evaluation of the radioprotective effects of thymoquinone on dynamic thiol-disulphide homeostasis during total-body irradiation in rats(Oxford Univ Press, 2019) Deniz, Cigdem Damla; Aktan, Meryem; Erel, Ozcan; Gurbilek, Mehmet; Koc, MehmetIonizing radiation-induced free radicals cause functional and structural harmful effects. Thiol, an important antioxidant, plays a major role in the eradication of reactive oxygen molecules. Thiol/disulphide homeostasis is a marker of oxidative stress. The objective of this study was to assess the potential radioprotective effects of thymoquinone (TQ) on the dynamic thiol/disulphide homeostasis of rats receiving total-body irradiation (IR). Twenty-two rats were divided into three groups to test the radioprotective effectiveness of TQ. The sham control group did not receive TQ or IR. The IR group received only total-body IR. The TQ + IR group received IR plus TQ. Following IR, blood samples were taken. The thiol/disulphide homeostasis parameters were analysed by a newly established method. In the IR group, native thiol and the native thiol/total thiol ratio were significantly decreased (P = 0.003 and P = 0.003, respectively), whereas the disulphide/native thiol and disulphide/total thiol ratios were significantly increased when compared with those of the sham control group (P = 0.003 and P = 0.003, respectively). In the TQ + IR group, the mean disulphide, native thiol and total thiol levels and the disulphide/native thiol, disulphide/total thiol and native thiol/total thiol ratios were not found to be significantly different when compared with those of the sham control group (P > 0.05 for all). Thiol/disulphide homeostasis was found to be disturbed after IR exposure. The results showed that TQ had antioxidant effects and reduced the IR-induced oxidative stress, which was demonstrated through the dynamic thiol/disulphide homeostasis. Thus, the use of TQ before radiation treatment helped protect the rats from oxidant side effects.Öğe Evaluation of the relationship of erythrocyte membrane Na plus /K plus -ATPase enzyme activity and tumor response to chemoradiotherapy in patients diagnosed with locally advanced nonsmall cell lung cancer and glioblastoma multiforme(Wolters Kluwer Medknow Publications, 2018) Cetinkaya, Cigdem Damla; Gurbilek, Mehmet; Koc, MehmetContext: Radiotherapy is the commonly used therapeutic modality for inoperable cancer types. We investigated chemoradiotherapy (CRT) effects on the Na+/K+-ATPase enzyme. Aims: The aim of the present study was to determine the usefulness of Na+/K+-ATPase enzyme as a prognostic factor and as a potential target for increasing the CRT response of nonsmall cell lung cancer (NSCLC) and glioblastoma multiforme (GBM). Settings and Design: We prospectively evaluated 30 patients (all were treated with CRT) and 20 healthy controls. Subjects and Methods: Blood samples were taken before and after the completion of CRT from the patients and once from the control group. Erythrocyte membranes were isolated and Na+/K+-ATPase enzyme activities were measured. Statistical Analysis Used: The statistical significance was calculated using the one-way analysis of variance test and the Tukey's test. Results: Na+/K+-ATPase activity levels were increased in the patient groups before completion of CRT CRT, when compared to the control group. A significant decrease in Na+/K+-ATPase activity was noted in the patient groups after the completion of CRT when compared to before CRT, but the activity remained higher than in the control group. No relationship was noted between survival and Na+/K+-ATPase activity in NSCLC and GBM patients. Conclusion: Levels of Na+/K+-ATPase activity were initially high in patients with NSCLC and GBM, and decreased after the completion of CRT. This supports a linkage between the altered activity of Na+/K+-ATPase and the treatment effects of CRT. The observed change in Na+/K+-ATPase activity in cancer patients receiving CRT suggests that targeting this enzyme could represent a novel mean of combatting NSCLC and GBM.Öğe The Influence of Hormone Therapy on the Development of Pulmonary Fibrosis after Radiotherapy in Patients with Breast Cancer(Akad Doktorlar Yayinevi, 2022) Yavuz, Berrin Benli; Poyraz, Necdet; Kanyilmaz, Gul; Aktan, Meryem; Tuncez, Ismail H.; Koc, MehmetThe aim of the present study is to investigate the effects of hormone therapy on pulmonary fibrosis in patients who received curative conformal radiotherapy for breast cancer. Data of 469 patients were evaluated. Computerized tomography images were evaluated by a radiologist as blindly. The influence of hormone therapy (tamoxifen and aromatase inhibitors), age, menopause, radiotherapy fields, ipsilateral lung volume receiving 5 Gy (V5), ipsilateral lung volume receiving 20 Gy (V20), ipsilateral mean lung dose (MLD) and the effects of taxane group of chemotherapy on pulmonary fibrosis were investigated. The mean age was 51 (range 27-83) years. As hormone therapy, 159 patients (33.9%) used tamoxifen and 253 patients (53.9%) used aromatase inhibitors. A significant relationship was found between both 6th month lung fibrosis and 2nd year lung fibrosis, and V5, V20, MLD, regional lymphatic irradiation and hormone therapy use. More grade 2 fibrosis was detected in the patients who received tamoxifen compared to the patients who received aromatase inhibitors and the control group (p< 0.001). No association was found between menopausal status, age, and taxane group chemotherapy and lung fibrosis development. In multivariate analysis, V5, MLD, and using hormone therapy were shown to be independent predictors of the risk of developing fibrosis at both 6 months and 2 years. Use of tamoxifen increases early and late lung fibrosis more than aromatase inhibitors in patients who receive radiotherapy for breast cancer. However, V5, V20, MLD and regional lymph node irradiation also contribute to the prevalence of fibrosis.Öğe Outcomes of reirradiation in the treatment of patients with multiple brain metastases of solid tumors: a retrospective analysis(Ame Publ Co, 2015) Aktan, Meryem; Koc, Mehmet; Kanyilmaz, Gul; Tezcan, YilmazBackground: Patients with multiple brain metastases are often treated with whole brain radiation therapy (WBRT). Second course of WBRT is an important treatment option for patients with clinical or radiological intracranial disease progression. This study examines the outcomes in patients with multiple brain metastases who underwent reirradiation. Methods: We examined the medical records of 34 patients with multiple brain metastases who were treated WBRT. The median dose for the first course of WBRT was 30 Gy (range, 25-30 Gy) and for the second course 25 Gy (range, 20-30 Gy). Statistical analyses were performed with using Cox regression analyses, log-rank test and Kaplan-Meier method. Results: The median Karnofsky performance status (KPS) was 80 (range, 50-100) before reirradiation. Patients with KPS of >70 had a median survival of 11.4 months, compared to 2.2 months with KPS of <= 70 (P=0.012) and patients who have severe symptoms at the time of reirradiation with median survival 2.2 months while those with mild symptoms had a median of 4.8 months survival (P=0.08). The median overall survival for all patients after diagnosis of metastases was 24.7 months, after the re-irradiation WBRT (re-WBRT) it was 5.3 months (95% CI, 4.08-6.62) and from the diagnosis of primary tumor was 27.1 months (95% CI, 17.75-37.04). Conclusions: In select patients who have good performance status and who do not have severe symptoms might benefit from re-WBRT and re-WBRT seems to be associated with minimal toxicity in patients treated with lower palliation doses.Öğe Prognostic Importance of Ki-67 Labeling Index in Grade II Glial Tumors(Kare Publ, 2018) Kanyilmaz, Gul; Onder, Hatice; Aktan, Meryem; Koc, Mehmet; Bora, Huseyin; Karahacioglu, Eray; Erkal, Haldun SukruOBJECTIVE To date, several methods have been identified for predicting the prognostic subgroups of grade II gliomas; however, these methods have some limitations in predicting survival. So, we aimed to determine the predictive role of Ki-67 labeling, index (LI) on survival. METHODS Between 1995 and 2011, patients with grade II, gliomas were retrospectively analyzed. All patients received radiotherapy (RT). RESULTS This study included 78 patients with median 44 (range, 6-137) months follow-up. Patients aged >= 40 years had a poorer overall survival (OS) than those aged <10 years (p=0.04). Patients with gross total resection/ subtotal resection had a longer OS than those with biopsy/partial resection (p=0.001). If the disease had recurrence or progression during the follow-up period, the patients had a poorer OS (p=0.01). Patients with a Ki-67 LI >= 4% had a poorer OS than those with Ki-67 LI < 4%(p=0.001). The extent of resection, recurrence, or progression, and Ki-67 LI >= 4% were the independent prognostic factors for OS. CONCLUSION In our opinion, Ki-67 LI is an important prognostic factor for grade II gliomas, hut it cannot be used as a diagnostic measure alone. It must be used in combination with the other prognostic factors.Öğe Prognostic importance of PTEN, EGFR, HER-2, and IGF-1R in gastric cancer patients treated with postoperative chemoradiation(Tubitak Scientific & Technological Research Council Turkey, 2019) Benli Yavuz, Berrin; Koc, Mehmet; Kozacioglu, Sumeyye; Kanyilmaz, Gul; Aktan, MeryemBadcground/aim: This study aimed to describe the prognostic importance of epidermal growth factor (EGFR), phosphatase and tensin homolog (PTEN), human EGF receptor-2 (HER-2), and insulin-like growth factor 1 receptor (IGF-1R) in gastric cancer patients treated with postoperative chemoradiation therapy. Materials and methods: Sixty-nine patients treated with adjuvant chemoradiation therapy were retrospectively evaluated. Tumor samples were stained immunohistochemically. Results: All patients were treated with 3D conformal radiation therapy with concomitant and adjuvant chemotherapy. Perineural invasion (PNI) (P = 0.042), prechemoradiation therapy albumin levels below 3.5 mg/dL (P = 0.011), and EGFR positivity (P = 0.008) had negative effects on overall survival (OS). The median OS was 26 months for patients with PNI (+), 34.9 months for those with PNI (-), 19.5 months for those with albumin levels below 3.5 mg/dL, and 33.2 months for those with albumin levels above 3.5 mg/dL. IGF-1R (+) (P= 0.035) and history of cigarette smoking (P= 0.033) were observed to have a statistically significantly negative effect on disease-free survival (DFS). The median DFS was 29.2 months for IGF-1R (+) patients, 37.9 months for those with IGF-1R (-), and 26.3 and 40.59 months for smokers and nonsmokers, respectively. Condusion: IGF-1R and EGFR may be used for patient selection in future prospective studies that evaluate the prognostic importance of these receptors.Öğe Prognostic Value of IDH-1, PTEN and EGFR Expression in High Grade Gliomas(Akad Doktorlar Yayinevi, 2019) Aktan, Meryem; Findik, Sidika; Kanyilmaz, Gul; Yavuz, Berrin Benli; Koc, MehmetGliomas are the most common primary brain tumors in adults. Despite advances in modem diagnostic procedures and therapies, the prognosis is still poor. To improve survival and the knowledge about the biological and clinical presentation of gliomas, more individualised and targeted treatments are needed. The aim of this study was to correlate the immunostaining patterns of isocitrate dehydrogenase-1 (IDH-1), phosphatase and tensin homolog (PTEN) and epidermal growth factor (EGFR) with progression-free survival (PFS) and overall survival (OS) in high grade gliomas patients. We analized 60 high grade gliomas who underwent surgery and standard chemoradiotherapy. Immunohistochemical methods were used to classify the IDH-1 gene mutation presence, staining patterns of PTEN and EGFR in tumor samples of the diagnosis. Median follow-up time was 18.9 months. There was significant relation between IDH-1 mutation and OS. Median OS was 37.9 months for patients with IDH-1 mutation, 12.4 months for patients with no mutation (p< 0.001). Median PFS was 29.8 months for patients with no IDH-1 mutation and 70.4 months for patients with IDH-1 mutation (p= 0.03). There was no significant relation between PTEN and EGFR immunopattern and OS or PFS in univariate analysis. However, there was significant relation between immunoreactivity of PTEN and OS (p= 0.03), immunointensity of PTEN and OS (p= 0.02) in multivariate analysis. In conclusion, the relationship between EGFR mutation and OS and PFS can also be demonstrated by studies with more patients.Öğe Prognostic value of pre-treatment 18F-FDG-PET uptake in small-cell lung cancer(Springer, 2017) Aktan, Meryem; Koc, Mehmet; Kanyilmaz, Gul; Yavuz, Berrin BenliPurpose Small-cell lung cancer (SCLC) is an aggressive disease, despite an initially favorable response to treatment, and its prognosis is still poor. Multiple parameters have been studied as possible prognostic factors, but none of them are reliable enough to change the treatment approach. F-18-fluorodeoxyglucose-positron emission tomography (FDG-PET) is a novel imaging technique for staging of SCLC. The aim of this study was to evaluate the prognostic value of pre-treatment FDG-PET parameters on clinical outcome in limited stage (LS) SCLC patients treated with curative thoracic radiotherapy (RT) and chemotherapy. Clinical records of 46 LS-SCLC patients with pre-treatment FDG-PET imaging were retrospectively reviewed. Patients were treated with definitive RT for a total dose of 50-60 Gy and chemotherapy. The clinical endpoints were progression-free survival (PFS) and overall survival (OS). The median age was 59 (range 30-82) years, and median follow-up time was 23.2 months (range 5-82.8 months). Median OS was 30.9 months for pre-treatment tumor maximum standardized uptake value (SUVmax) < 9.3 and 20.6 months for SUVmax ae9.3 (p = 0.027) and PFS was 55.6 months for SUVmax < 9.3 and 38.6 months for SUVmax ae9.3 (p = 0.16). Median OS was 73 months for pre-treatment lymph node SUVmax < 5.8 and 21 months for ae5.8 (p = 0.01) and PFS was 38.6 months (range 6.8-70.3 months) for SUVmax-LN ae5.8; all patients with SUVmax-LN < 5.8 were alive (p = 0.07). Median survival time was 28.2 months (range 21.7-34.7 months) for patients younger than 65 and 8.7 months (range 5.7-11.8 months) for those ae65 years (p = 0.00). Pre-treatment FDG-PET uptake may be a valuable tool to evaluate prognosis in SCLC patients. Patients with a higher pre-treatment FDG uptake may be considered at increased risk of failure and may benefit from more aggressive treatment approaches.Öğe Radiation-induced hypothyroidism in patients with breast cancer: a retrospective analysis of 243 cases(Elsevier Science Inc, 2017) Kanyilmaz, Gul; Aktan, Meryem; Koc, Mehmet; Demir, Hikmettin; Demir, Lutfi SaltukThis study aims to estimate the incidence of hypothyroidism (HT) and to evaluate the predictors affecting the development of HT after radiotherapy (RT) for breast cancer, with a focus on radiation dose-volumetric parameters. Between 2009 and 2015, 243 patients undergoing RT for breast cancer were retrospectively analyzed. Free triiodothyronine (FT3), free thyroxin (FT4), and thyrotropin (TSH) were monitored before and after RT. The relation between the doses to thyroid gland (D-mean, D-max, D-min), percentage of thyroid volume receiving > 10 Gy, 20 Gy, 30 Gy, 40 Gy, and 50 Gy (V10 to V50), absolute thyroid volume, and HT were analyzed. The risk of HT according to radiation fields and the other clinic factors were also evaluated. The median follow-up was 41 (range; 6 to 130) months. Sixty-seven percent of the patients received RT to the breast/chest wall and ipsilateral supraclavicular fossa. Of 243 patients, 51 (21%) were diagnosed with HT. The median time to the onset of HT was 27 (range; 5 to 64) months. There were no significant relationships observed between Dmin or V10 to V50 and HT. The surgery type, clinical stage, nodal status, RT field, Dmean, and Dmax were statistically significant predictors for HT in univariate analysis. The Dmean was the only prognostic factor predicting HT in multivariate analysis, and Dmean > 21 Gy was a threshold value for the evolvement of HT. In this study, we present evidence that postoperative irradiation of patients with breast cancer may frequently lead to HT. Patients who have received RT for breast cancer, especially irradiation on the supraclavicular region, may require thyroid function screening after RT. (C) 2017 American Association of Medical Dosimetrists.Öğe The role of melatonin in preventing radiation-induced intestinal injury(Imprimatur Publications, 2021) Sezen, Orhan; Erdemci, Burak; Calik, Muhammet; Koc, MehmetPurpose: Despite the therapeutic effects of radiotherapy on tumor cells, it has potential severe adverse effects on the sur- rounding normal tissues. Acute or chronic intestinal adverse effects that are likely to occur in patients undergoing radio- therapy for pelvic and abdominal cancers lead to increased morbidity, significant impairment of the quality of life, and economic losses. Various biological, chemical and pharma- cological agents are being tested to protect from and to treat radiation enteritis. This experimental study aimed to inves- tigate the protective effects of melatonin against radiation induced intestinal injury when administered before radiation exposure in rats. Methods: In the present study, villus height and the number of villi in the ileum and jejunum of rats receiving two dif- ferent doses of intraperitoneal melatonin (5 and 10 mg/kg) prior to a single fraction of radiation given at a dose of 8 Gy to the abdominal region, was evaluated by histopathological examination 3 and 7 days after radiation exposure. Results: At a dose of 5 mg/kg, melatonin was found to be effective in preventing radiation-induced injury to villus height in the jejunum and the number of villi in the ileum and jejunum, and at a dose of 10 mg/kg it was also effective in preventing radiation-induced injury to villus height in the ileum. Conclusions: Melatonin is effective for the prevention of radiation-induced intestinal injury. This outcome can be considered an evidence to test melatonin in clinical trials.Öğe The role of radiotherapy after radical prostatectomy(Tubitak Scientific & Technological Research Council Turkey, 2015) Aktan, Meryem; Koc, Mehmet[Abstract Not Availabe]Öğe Survival following reirradiation using intensity-modulated radiation therapy with temozolomide in selected patients with recurrent high grade gliomas(Ame Publ Co, 2015) Aktan, Meryem; Koc, Mehmet; Kanyilmaz, GulBackground: High grade gliomas often recur after initial treatment. Despite so many treatment options, there is no standard treatment for recurrent gliomas. The aim of this study is to offer survival following reirradiation (re-RT) using intensity-modulated radiation therapy (IMRT) with temozolomide in selected patients with recurrent high grade gliomas. Methods: We examined the medical records of 21 adult patients with recurrent high grade gliomas who were reirradiated with IMRT at the time of tumor recurrence or progression. Tumor recurrence was shown by gadolinium-enhanced magnetic resonance imaging (MRI) and diagnosis was established by pathology review. Statistical analyses were performed with SPSS version 18.0.1 using Cox regression analyses, log-rank test and Kaplan-Meier method. Results: Eighteen patients presented by localized recurrence, three patients with diffuse recurrence. Median radiotherapy (RT) dose was 54 Gy. About 81% patients received temozolomide with re-RT. The time interval between two courses RT was median 39.3 months (range, 9.6-140.8 months). The response was checked by MRI. About 24% patients achieved complete response (CR) and 29% patient partial response (PR). Stable disease (SD) was observed in 47% patients. Median follow-up time from diagnosis was 41.4 months (range, 16.6-145.4 months) and 12.3 months (range, 2-27.6 months) from re-RT. Median time to recurrence was 39.3 months (range, 9.6-140.8 months). Median survival after re-RT was 18 months for anaplastic astrocytoma (AA), 14.1 months for glioblastoma multiforme (GBM) (range, 11-17.2 months) (P=0.1) and 7.1 months for patients with Karnofsky performance status (KPS) <70 before re-RT and 17.4 months for KPS >70 (P=0.02). Conclusions: re-RT is one of the treatment options for recurrent high grade gliomas and IMRT can be an effective treatment modality for recurrent high grade brain tumors with only mild side effects. Survival is better in patients with good performance status and in recurrent anaplastic tumors after re-RT.Öğe Two cases of gastrointestinal stromal tumor of the small intestine with liver and bone metastasis(Ame Publ Co, 2015) Aktan, Meryem; Koc, Mehmet; Yavuz, Berrin Benli; Kanyilmaz, GulGastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of the gastrointestinal tract. These tumors most commonly occur in the stomach (60%), jejunum and ileum (30%). Metastasis is characteristically the malignant behavior of the GISTs. GISTs most frequently metastasize to the liver and peritoneum, whereas bone and lung metastases are uncommon sites. Here, we described two cases of bone and liver metastases in patients with advanced GISTs. Both of them showed liver metastasis at disease presentation and bone metastasis in early time after the diagnosis. Bone metastases involved the lumber spine and right femur in first patient and L2 vertebral body in the second case. All of the lesions presented a lytic pattern. These cases are presented because of the rare incidence of bone metastasis to femur and vertebral bodies. More attention should be paid to the diagnosis of bone metastases from GISTs in clinical practice despite the shortage of available data on the sensitivity and specificity of bone scintigraphy and PET-CT.Öğe Unplanned irradiation of internal mammary lymph nodes in breast cancer(Springer-Verlag Italia Srl, 2017) Kanyilmaz, Gul; Aktan, Meryem; Koc, Mehmet; Demir, Hikmettin; Demir, Lutfi SaltukTo evaluate the incidental dose to the internal mammary chain (IMC) in patients treated with three-dimensional conformal radiotherapy, to estimate the predictors affecting the magnitude of IMC receiving dose and to determine the predictive role of clinical parameters on survival. Between 2009 and 2015, 348 patients undergoing RT for breast cancer were retrospectively analyzed. All patients underwent our department's routine procedure for breast cancer. The internal mammary lymph nodes were contoured according to Radiation Therapy Oncology Group (RTOG) concensus. Based on each patient's dose-volume histograms, the mean doses (D (mean)) to internal mammary gland were analyzed. Overall survival and disease-free survival were also evaluated. The median follow-up time was 38 (range 3-80) months. The D (mean) to IMC was 32.8 Gy and the dose delivered to IMC showed a greater coverage in modified radical mastectomy (MRM) group compared with breast conserving surgery (34.6 vs 26.7 Gy). The T-stage of tumor and the N-stage of tumor affected the incidental dose to IMC. The tumor size, the number of involved lymph nodes, the percentage of involved lymph nodes, hormonal status, advanced T-stage and advanced N-stage were the prognostic factors that affect survival. The IMC received meaningful incidental irradiation dose when treated with two opposite tangential fields and ipsilateral supraclavicular fossa with a single anterior field. The real effect of incidental dose on survival and the hypothesis about the benefit of incidental irradiation of IMC should be examined in clinical studies.Öğe THE USE OF ACUTE-PHASE PROTEINS APACHE II AND SOFA TO PREDICT THE MORTALITY OF COVID-19 PATIENTS(Nobel Ilac, 2023) Deniz, Cigdem Damla; Visneci, Emin Fatih; Eryilmaz, Mehmet Ali; Tutar, Mahmut Sami; Iyisoy, Mehmet Sinan; Ugur, Ayse Ruveyda; Koc, MehmetObjective: Acute-phase proteins are a family of proteins synthesized by the liver. With this study, we aimed to investigate the effects of COVID-19 infection on acute phase reactants (AFR) and determine the usability of AFRs as prognostic factors in COVID-19 disease.Material and Method: Serum samples taken for routine analysis of the patients admitted to the Emergency Department and diagnosed with COVID-19, were used. AFR levels of 30 patients who resulted in mortality and 30 recovered patients were evaluated. C-reactive protein (CRP), ferritin (FER), ceruloplasmin (Cp), albumin (Alb), prealbumin (Prealb), transferrin (Trf), lactate, Acute Physiology and Chronic Health Evaluation (APACHE), and Sequential Organ Failure Assessment (SOFA) assessment was performed.Results: The hazard ratio and 95% confidence interval for FER, CRP, lactate, Alb, Cp, Prealb, Trf, Age, SOFA, and APACHE were 1.001 (1.000-1.001), 1.005 (1.001- 1.008), 1.141 (1.016-1.243), 1.016 (0.740-1.399), 1.016 (0.740-1.399), 1.056 (1.017-1.100), 0.978 (0.917-1.035), 1.000 (0.995-1.006), 1.032 (1.004- 1.064), 1.104 (0.971-1.247), and 1.012 (0.974-1.051), respectively, in univariable model. Only CRP, lactate, and FER found significant in multivariable model. In addition, patients in the nonsurvivors group had significantly higher FER, CRP, lactate, APACHE, age, and SOFA. Nonsurvivors also had lower Alb, Prealb, and serum Trf level compared to survivors.Conclusion: CRP, lactate, and FER, which we have shown to be significantly higher in severe COVID-19 patients, will be valuable parameters that will contribute to clinical improvement if they are used in the follow-up of patients due to their easy measurement and predictive values.
