Person: OCAK, BİROL
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Publication Clinical and laboratory outcomes of solid cancer patients reinfected with sars-cov-2(Elsevier, 2021-09-21) Yazici, O.; Unsal, O.; Ozdemir, N.; Uner, A.; Ozet, A.; Cubukcu, E.; ÇUBUKÇU, ERDEM; Ocak, B.; OCAK, BİROL; Tıp Fakültesi; Onkoloji Ana Bilim Dalı; 0000-0001-7537-1699; 0000-0001-8731-9636; ABC-9831-2021Publication The ki-67 proliferation index predicts recurrence-free survival in patients with dermatofibrosarcoma protuberans(Assoc Basic Medical Sci Federation Bosnia & Herzegovina Sarajevo, 2021-01-01) Tanriverdi, Ozgur; Ozsen, Mine; ÖZŞEN, MİNE; Deligonul, Adem; DELİGÖNÜL, ADEM; Yazici, Serkan; YAZİCİ, SERKAN; Cetintas, Sibel Kahraman; Yalcinkaya, Ulviye; YALÇINKAYA, ÜLVİYE; Sahin, Ahmet Bilgehan; ŞAHİN, AHMET BİLGEHAN; Orhan, Sibel Oyucu; OYUCU ORHAN, SİBEL; Ocak, Birol; OCAK, BİROL; Evrensel, Turkkan; EVRENSEL, TÜRKKAN; Kahveci, Ramazan; KAHVECİ, RAMAZAN; Cubukcu, Erdem; ÇUBUKÇU, ERDEM; Tıp Fakültesi; Onkoloji Ana Bilim Dalı; 0000-0001-6407-0962; 0000-0002-5771-7649; 0000-0002-7846-0870; 0000-0002-0598-7284; 0000-0001-7537-1699; AAJ-8314-2021; AEC-2238-2022; AAM-4927-2020; M-2172-2015Dermatofibrosarcoma protuberans (DFSP) is an uncommon soft tissue sarcoma that originates from the dermis or subcutaneous tissue in the skin. While its prognosis is generally favorable, disease recurrence is relatively frequent. Since morbidity after repeated surgery may be significant, an optimized prediction of recurrence-free survival (RFS) has the potential to improve current management strategies. The purpose of this study was to investigate the prognostic value of the Ki-67 proliferation index with respect to RFS in patients with DFSP We retrospectively analyzed data from 45 patients with DFSP. We calculated the Ki-67 proliferation index as the percentage of immunostained nuclei among the total number of tumor cell nuclei regardless of the intensity of immunostaining. We constructed univariate and multivariate Cox proportional hazards regression models to identify predictors of RFS. Among the 45 patients included in the study, 8 developed local recurrences and 2 had lung metastases (median follow-up: 95.o months; range: 5.2-412.4 months). The RFS rates at 60, 120, and 240 months of follow-up were 83.8%, 76.2%, and 65.3%, respectively. The median Ki-67 proliferation index was 14%. Notably, we identified the Ki-67 proliferation index as the only independent predictor for RFS in multivariate Cox proportional hazards regression analysis (hazard ratio = 1.106, 95% confidence interval = 1.019-1.200, p = 0.016). In summary, our results highlight the potential usefulness of the Ki-67 proliferation index for facilitating the identification of patients with DFSP at a higher risk of developing disease recurrences.Publication Platin-based chemotherapy does not improve survival in patients with non-metastatic resected typical carcinoid tumors(Spandidos Publ Ltd, 2022-10-01) Şahin, Ahmet Bilgehan; Melek, Hüseyin; Ocak, Birol; Oyucu Orhan, Sibel; Erkan, Buket; Caner, Burcu; Deligönül, Adem; Çubukcu, Erdem; Bayram, Ahmet Sami; Akyıldız, Elif Ülker; Evrensel, Türkkan; ŞAHİN, AHMET BİLGEHAN; MELEK, HÜSEYİN; OCAK, BİROL; OYUCU ORHAN, SİBEL; ERKAN ÖZMARASALI, BUKET; CANER, BURCU; DELİGÖNÜL, ADEM; ÇUBUKÇU, ERDEM; BAYRAM, AHMET SAMİ; AKYILDIZ, ELİF ÜLKER; EVRENSEL, TÜRKKAN; Tıp Fakültesi; Tıbbi Onkoloji Ana Bilim Dalı; 0000-0002-7846-0870; 0000-0003-0684-0900; 0000-0003-1822-8153; 0000-0001-8217-3471; 0000-0003-1591-3323; AAM-4927-2020; AAI-5039-2021; AEC-2238-2022; AAJ-8314-2021; CPN-8681-2022; HJH-6371-2023; ESM-4544-2022; ETP-1691-2022; ABB-7580-2020; ELN-4128-2022; EXZ-0745-2022Chemotherapy is controversial in non-metastatic typical carcinoid (TC) tumors. Therefore, it was aimed to evaluate the impact of platin-based chemotherapy on the survival of patients with lung TC. The medical records of patients who underwent surgical resection for non-metastatic TC from 2002 to 2020 at our institution were retrospectively reviewed. Multivariate regression analysis was performed for chemotherapy and prognostic factors in disease-free survival (DFS) in 72 patients. The pathological stages of patients were as follows: 73.6% of the patients were in stage I, 15.3% in stage II and 11.1% in stage III. A total of 5 patients (6.9%) received platin-based chemotherapy and 6 patients (8.3%) had recurrences. The DFS rates at 12, 36 and 60 months were 98.5, 95.1 and 92.5%, respectively. Log-rank testing showed that patients who received chemotherapy and had stage III disease had shorter DFS (P=0.021 for chemotherapy and P<0.001 for stage). However, multivariate analysis revealed that the pathological stage was the only statistically significant factor affecting DFS (P=0.016). Platin-based chemotherapy did not improve DFS, and the eighth edition of TNM (tumor, nodes, metastases) staging did have prognostic value for patients with non-metastatic TC. Although resection has satisfying long-term outcomes, studies on new agents are needed to decrease the recurrence rate, particularly in patients with stage III disease.Publication Chemo-immunotherapy with atezolizumab in extensive-stage small-cell lung cancer; single-center experience(Akad Doktorlar Yayınevi, 2020-01-01) Şahin, Ahmet Bilgehan; Çubukcu, Erdem; Ocak, Birol; Deligönül, Adem; Kaçan, Turgut; Orhan, Sibel Oyucu; Evrensel, Türkkan; ŞAHİN, AHMET BİLGEHAN; ÇUBUKÇU, ERDEM; OCAK, BİROL; DELİGÖNÜL, ADEM; OYUCU ORHAN, SİBEL; EVRENSEL, TÜRKKAN; Tıp Fakültesi; Tıbbi Onkoloji Ana Bilim Dalı; 0000-0002-7846-0870; 0000-0001-7537-1699; 0000-0001-8217-3471; 0000-0002-9732-5340; AAJ-8314-2021; AAJ-1027-2021; AAM-4927-2020; ETP-1691-2022; HHA-1866-2022; ESM-4544-2022Chemo-immunotherapy (CIT) with platin, etoposide and monoclonal antibodies targeting the PD-1/PDL-1 pathway has recently improved survival in extensive-stage small-cell lung cancer (SCLC) after decades. We aimed to investigate the efficacy and safety of CIT with atezolizumab in extensive-stage SCLC in chemotherapy naive patients. Eleven patients who were treated and followed in our center were included in this retrospective observational study. All the patients received carboplatin, etoposide and atezolizumab in the induction phase and atezolizumab in the maintenance phase. The Kaplan-Meier test was used to determine progression-free survival (PFS) and overall survival (OS), and the effects of the sites of metastasis were analyzed using the log-rank test. The median age was 69.9 years, and 81.8% were male. The median number of CIT and total atezolizumab cycles was 4 and 7, respectively. 63.6% received maintenance therapy. Median PFS was 5.2 months (95% CI: 3.4-6.9), and median OS was 11.3 months (95% CI: 1.0-21.5). The overall response rate was 63.6%. There was no significant difference between patients with and without liver metastasis in terms of PFS and OS. We observed toxicity higher than grade 2 in more than half of the patients, and hematological toxicities were prominent. CIT with carboplatin, etoposide and atezolizumab is efficient and safe in extensive-stage SCLC considering the PFS, OS, response rates, 12-month survival rate, and side effects. The progression of liver lesions was remarkable. Cranial and thoracic radiation are issues that should be discussed in the future with data from clinical studies.Publication The impact of ki-67 index, squamous differentiation, and several clinicopathologic parameters on the recurrence of low and intermediate-risk endometrial cancer(Assoc Basic Medical Sci Federation Bosnia & Herzegovina Sarajevo, 2021-01-01) Ocak, Birol; Atalay, Fatma Oz; Sahin, Ahmet Bilgehan; Ozsen, Mine; Dakiki, Bahar; Ture, Seray; Mesohorli, Merve; Odman, Hikmet Utku; Tanriverdi, Ozgur; Ocakoglu, Gokhan; Bayrak, Mehmet; Ozan, Hakan; Demiroz, Candan; Sali, Seda; Orhan, Sibel Oyucu; Deligönül, Adem; Çubukcu, Erdem; Evrensel, Turkkan; Ocak, Birol; OCAK, BİROL; Sahin, Ahmet Bilgehan; ŞAHİN, AHMET BİLGEHAN; Atalay, Fatma Oz; ÖZ ATALAY, FATMA; Ozsen, Mine; ÖZŞEN, MİNE; Dakiki, Bahar; DAKİKİ KORUCU, BAHAR; Ture, Seray; TÜRE AYDIN, SERAY; Mesohorli, Merve; Odman, Hikmet Utku; Ocakoglu, Gokhan; OCAKOĞLU, GÖKHAN; Bayrak, Mehmet; Ozan, Hakan; OZAN, HAKAN; Demiroz, Candan; DEMİRÖZ ABAKAY, CANDAN; Sali, Seda; SALİ, SEDA; Orhan, Sibel Oyucu; OYUCU ORHAN, SİBEL; Deligonul, Adem; DELİGÖNÜL, ADEM; Cubukcu, Erdem; ÇUBUKÇU, ERDEM; Evrensel, Turkkan; EVRENSEL, TÜRKKAN; Tıp Fakültesi; Onkoloji Ana Bilim Dalı; 0000-0001-7537-1699; 0000-0002-7188-6115; 0000-0002-7846-0870; 0000-0002-5771-7649; 0000-0001-9255-2475; 0000-0002-1114-6051; 0000-0003-1600-333X; AEC-2238-2022; ABA-2897-2021; AAH-5180-2021; AAM-4927-2020; AAJ-8314-2021Endometrial endometrioid carcinoma (EEC) represents approximately 75-80% of endometrial carcinoma cases. Three hundred and thirty-six patients with EEC followed-up in the authors' medical center between 2010 and 2018 were included in our study. Two hundred and seventy-two low and intermediate EEC patients were identified using the European Society for Medical Oncology criteria and confirmed by histopathological examination. Recurrence was reported in 17 of these patients. The study group consisted of patients with relapse. A control group of 51 patients was formed at a ratio of 3:1 according to age, stage, and grade, similar to that in the study group. Of the 17 patients with recurrent disease, 13 patients (76.5%) were Stage 1A, and 4 patients (23.5%) were Stage 1B. No significant difference was found in age, stage, and grade between the case and control groups (p > 0.05). Body mass index, parity, tumor size, lower uterine segment involvement, squamous differentiation (SqD), and Ki-67 index with p<0.25 in the univariate logistic regression analysis were included in the multivariate analysis. Ki-67 was statistically significant in multivariate analysis (p = 0.018); however, there was no statistical significance in SqD and other parameters. Our data suggest that the Ki-67 index rather than SqD needs to be assessed for recurrence in patients with low- and intermediate-risk EEC.Publication Why do some patients with stage 1a and 1b endometrial endometrioid carcinoma experience recurrence? A retrospective study in search of prognostic factors(Via Medica, 2022-01-01) Tanrıverdi, Özgür; Ocak, Birol; OCAK, BİROL; Şahin, Ahmet Bilgehan; ŞAHİN, AHMET BİLGEHAN; Atalay, Fatma Oz; ÖZ ATALAY, FATMA; Özsen, Mine; ÖZŞEN, MİNE; Dakiki, Bahar; DAKİKİ KORUCU, BAHAR; Türe, Seray; TÜRE AYDIN, SERAY; SALİ, SEDA; Bayrak, Mehmet; OZAN, HAKAN; DEMİRÖZ ABAKAY, CANDAN; Deligönül, Adem; DELİGÖNÜL, ADEM; Evrensel, Turkkan; ÇUBUKÇU, ERDEM; EVRENSEL, TÜRKKAN; Tıp Fakültesi; İç Hastalıkları Ana Bilim Dalı; 0000-0001-7537-1699; 0000-0002-7846-0870; 0000-0002-5771-7649; 0000-0001-9255-2475; 0000-0001-8407-0169; ABA-2897-2021; AEC-2238-2022; AAM-4927-2020Objectives: Endometrial endometrioid carcinoma (EEC) is the most encountered subtype of endometrial cancer (EC). Our study aimed to investigate the factors affecting recurrence in patients with stage 1A and 1B EEC. Material and methods: Our study included 284 patients diagnosed with the International Federation of Gynecology and Obstetrics stage 1A/1B EEC in our center from 2010 to 2018. The clinicopathological characteristics of the patients were obtained retrospectively from their electronic files. Results: The median age of the patients was 60 years (range 31-89). The median follow-up time of the patients was 63.6 months (range 3.3-185.6). Twenty-two (7.74%) patients relapsed during follow-up. Among the relapsed patients, 59.1% were at stage 1A EEC, and 40.9% were at stage 1B. In our study, the one-, three-, and five-year recurrence-free survival (RFS) rates were 98.9%, 95.4%, and 92.9%, respectively. In the multivariate analysis, grade and tumor size were found to be independent parameters of RFS in all stage 1 EEC patients. Furthermore, the Ki-67 index was found to affect RFS in stage 1A EEC patients, and tumor grade affected RFS in stage 1B EEC patients. In the time-dependent receiver operating characteristic curve analysis, the statistically significant cut-off values were determined for tumor size and Ki-67 index in stage 1 EEC patients. Conclusions: Stage 1 EEC patients in the higher risk group in terms of tumor size, Ki-67, and grade should be closely monitored for recurrence. Defining the prognostic factors for recurrence in stage 1 EEC patients may lead to changes in follow-up algorithms.Publication Pazopanib in metastatic soft tissue sarcoma (STS): Results of a multi-institutional observational study.(Lippincott Williams & Wilkins, 2022-06-01) Bilici, Ahmet; Koca, Sinan; Karaagac, Mustafa; Eraslan, Emrah; Ocak, Birol; Aydin, Sabin Goktas; Goksu, Sema Sezgin; Paydas, Semra; Derin, Sumeyye; Ergun, Yakup; Yekegunduz, Emre; Erol, Cihan; Ozyukseler, Deniz Tataroglu; Demiray, Atike Gokcen; Karaca, Mustafa; Guc, Zeynep Gulsum; Menekse, Serkan; Cinkir, Havva Yesil; Gumusay, Ozge; Sakin, Abdullah; OCAK, BİROL; Tıp Fakültesi; Tıbbi Onkoloji Ana Bilim Dalı; LLD-9901-2024Publication Clinical and laboratory outcomes of the solid cancer patients reinfected with sars-cov-2(Future Medicine, 2021-11-26) Unsal, Oktay; Yazici, Ozan; Ozdemir, Nuriye; Uner, Aytug; Ozet, Ahmet; Cubukcu, Erdem; ÇUBUKÇU, ERDEM; Ocak, Birol; OCAK, BİROL; Tıp Fakültesi; Onkoloji Ana Bilim Dalı; 0000-0001-7537-1699; 0000-0001-8731-9636; AEC-2238-2022Lay abstract Solid cancer patients are at a higher risk than general population in terms of Coronavirus disease 2019 (COVID-19) infectivity and COVID-19-associated death and disease. It is also known that COVID-19 infection has a more severe course in immunocompromised patients. Solid cancer patients may be a vulnerable subgroup of patients to reinfection with COVID-19. The rate of reinfection was 3.1% (n = 32) in our study population of 1024 solid cancer patients who were tested positive on a COVID-19 PCR test. The death rate of the patients with solid cancer was 34.3% (n = 11). In addition, we demonstrated that intensive care follow-up is significantly longer during the reinfection period. It was demonstrated that the time between the last dose of chemotherapy for the patients and the reinfection COVID PCR positivity did not affect the death rate. The COVID-19 pandemic has affected people's daily lives and treatments in many aspects. Owing to the high death rate of reinfection, even if cancer patients have reinfection, our approach is to continue cancer treatment as soon as the patient is cured. Finally, we support the priority vaccination of cancer patients.Introduction: The objective of this study was to evaluate the clinical and laboratory outcomes of solid cancer patients who were reinfected with COVID-19. Methods: Patients who were tested negative on the Coronavirus disease 2019 (COVID-19) PCR test and those with improved clinical conditions after infection with COVID-19 were enrolled in this study. Patients who received a positive COVID-19 PCR test 28 days after the initial positive PCR test were considered as reinfected. Results: A total of 1024 patients with the diagnosis of solid malignancy and COVID-19 PCR positivity were examined. The reinfection rate was 3.1%. Mortality rate of reinfection was 34.3%. The serum ferritin and creatinine values in reinfection were found to be significantly higher than the first infection (respectively; p = 0.015, p = 0.014). Conclusion: This study has demonstrated one of the first preliminary clinical results of COVID-19 reinfection in solid cancer patients.Publication The predictive importance of body-mass index on response to neoadjuvant chemotherapy in patients with breast cancer(Karger, 2022-09-14) Emirzeoğlu, Levent; Arıcı, Serdar; Şahin, Ahmet Bilgehan; Ocak, Birol; Ak, Naziye; Ay, Seval; Mammadov, Elkhan; Turna, Hande; Bilici, Ahmet; ŞAHİN, AHMET BİLGEHAN; OCAK, BİROL; Tıp Fakültesi; Tıbbi Onkoloji Ana Bilim Dalı; 0000-0002-7846-0870; 0000-0001-7537-1699; LLD-9901-2024; AAM-4927-2020Purpose: To investigate the effects of body mass index (BMI) on the response to neoadjuvant chemotherapy (NACT) in Turkish patients with local and locally advanced breast cancer.Methods: The pathological responses for the breast and axilla were assessed according to the Miller-Payne grading (MPG) system. Tumors were grouped into molecular phenotypes and classified as response rates according to the MPG system after completion of NACT. A 90% or greater reduction in tumor cellularity was considered as good response to treatment. Additionally, patients were grouped according to BMI into <25 (group A) and >= 25 (group B).Results: In total, 647 Turkish women with breast cancer were included in the study. In the univariate analysis, age, menopause status, tumor diameter, stage, histological grade, Ki-67, estrogen receptor (ER) status, progesterone receptor (PR) status, human epidermal growth factor receptor 2 (HER2) status, and BMI were assessed to determine which of these factors were associated with a >= 90% response rate. Stage, HER2 positivity, triple-negative breast cancer (TNBC; ER-negative, PR-negative, and HER2 negative breast cancer), grade, Ki67 levels, and BMI were found to be the statistically significant factors for a >= 90% response rate. In the multivariate analysis, grade III disease, HER2 positivity, and TNBC were found to be the factors associated with a high pathological response. Meanwhile, hormone receptor (HR) positivity and a higher BMI were associated with a decreased pathologic response in patients receiving NACT for breast cancer.Conclusion: Our results show that a high BMI and HR positivity are associated with a poor response to neoadjuvant chemotherapy in Turkish patients with breast cancer. The findings presented in this study may guide novel studies to examine the NACT response in obese patients with and without insulin resistance.Publication The ki-67 index and neutrophile-lymphocyte ratio are prognostic factors in patients with low-risk endometrial cancer(Mre Press, 2021-04-21) Çubukcu, Erdem; Şahin, Ahmet Bilgehan; Atalay, Fatma Öz; Ocak, Birol; Özşen, Mine; Abakay, Candan Demiröz; Özerkan, Kemal; Hasanzade, Ulviyya; Mesahorlı, Merve; Deligönül, Adem; Ozan, Hakan; Evrensel, Türkkan; ÇUBUKÇU, ERDEM; ŞAHİN, AHMET BİLGEHAN; ÖZ ATALAY, FATMA; OCAK, BİROL; ÖZŞEN, MİNE; DEMİRÖZ ABAKAY, CANDAN; ÖZERKAN, KEMAL; HASANZADE, ULVIYYA; Mesahorlı, Merve; DELİGÖNÜL, ADEM; OZAN, HAKAN; EVRENSEL, TÜRKKAN; Tıp Fakültesi; Patoloji Ana Bilim Dalı; 0000-0002-7846-0870; 0000-0001-7537-1699; 0000-0002-5771-7649; 0000-0001-5380-5898; AAH-9791-2021; K-2269-2016; AAM-4927-2020; ETP-1691-2022; JHC-4482-2023; HHA-1866-2022; AAI-1609-2021; AAH-3855-2021; EXU-7466-2022; FNB-4540-2022; ESM-4544-2022; DKZ-4159-2022; EXJ-0967-2022Objective: To investigate the prognostic factors comparing clinical, histopathological, and laboratory parameters in low-risk endometrial cancer (EC). Methods: In the present single-center study, multivariate Cox regression analysis was performed on retrospective clinical and laboratory data and histopathological features obtained from the re-evaluation of 253 patients with low-risk EC. Receiver operating characteristic curves (ROC) were plotted for neutrophile-lymphocyte ratio (NLR), platelet-lymphocyte ratio, lymphocyte-monocyte ratio and Ki-67 index for recurrence. Kaplan-Meier analysis was employed for survival rates. Results: The median age was 58.5 years (32.0-75.4). Most of the patients were obese and post-menopausal. In nearly half of the patients, lymphadenectomy was performed in addition to hysterectomy and oophorectomy. The median tumor size was 30 mm (range 2-80), and the median Ki-67 index was 25 (1-90). According to the ROC curve analysis, the cut-off values for the Ki-67 index, NLR, PLR, and LMR were determined as >= 22, >= 1.98, >= 115.3, and >= 4.71, respectively. The log-rank test revealed that the patients with a Ki67 index lower than 22% and NLR lower than 1.98 had statistically longer recurrence-free survival (RFS) (p = 0.002 for Ki-67 index and p = 0.004 for NLR). The multivariate analysis revealed that the Ki-67 index and NLR were statistically significant factors for RFS (p = 0.012 and p = 0.029, respectively). Conclusion: The present study highlights the prognostic implications of both the Ki-67 index and NLR in lowrisk EC.