Birol Ocak

Dr. Birol Ocak

orcid

Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
14 September 2022 in Breast Care
Verified
Journal Article
Open access
PDF file
LELevent Emirzeoglu
Levent Emirzeoglu
SASerdar Arici
Serdar Arici
ASAhmet Bilgehan Sahin
Ahmet Bilgehan Sahin
BOBirol Ocak
Birol Ocak
NANaziye Ak
Naziye Ak
ABAhmet Bilici
Ahmet Bilici
Purpose: The aim of the study was 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 the completion of NACT. A 90% or greater reduction in tumor cellularity was considered a 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, Ki-67 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 pathological 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 NACT 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.

12 February 2021 in Bosnian Journal of Basic Medical Sciences
Verified
Journal Article
Open access
PDF file
SOSibel Oyucu Orhan
Sibel Oyucu Orhan
AŞAhmet Bilgehan Bilgehan Şahin
Ahmet Bilgehan Bilgehan Şahin
ECErdem Cubukcu
Erdem Cubukcu
ADadem deligonul
adem deligonul
BOBirol Ocak
Birol Ocak
TETürkkan Evrensel
Türkkan Evrensel
Kaposi sarcoma is a rare disease and there is a gap in the literature about which chemotherapeutics should be applied, especially for the classical type. We aimed to present our institutional data on the demographic characteristics, treatment, and treatment efficacy in 16 Kaposi sarcoma (KS) patients treated with chemotherapy. We retrospectively analyzed the demographic and clinical characteristics, and the chemotherapeutic agents administered to the 16 KS patients diagnosed in our center and treated with chemotherapy, based on the medical records obtained. The median age, gender, type of KS, site of involvement, cytotoxic agents administered, progression-free survival (PFS), overall survival (OS), objective response rate (ORR), disease control rate (DCR), and safety profiles of the patients were evaluated. The median age at disease onset was 61.07 years (range, 39.4–85.8 years). Among the patients, 1 had immunosuppression-related KS, 4 had AIDS-related KS, and 11 had classical KS. In the first-line cytotoxic therapy, 7 patients received pegylated-liposomal doxorubicin (PLD), 6 patients received paclitaxel, 2 patients received oral etoposide, and 1 patient received the adriamycin, bleomycin, and vincristine regimen. In the Kaplan–Meier analysis, the PFS was 39.9 months (95% CI, 7.7–72.0). In the first-line setting, a significant difference in terms of PFS was observed between the PLD- and paclitaxel-treated groups (not reached vs. 12.8 months, p = 0.033). The OS was 66.1 months (95% CI, 30.2–102.0). The ORR of the 16 patients was 43.8%, and their DCR was 81.3%. No grade 3 or 4 toxicity was observed. This retrospective study showed that PLD seems better than paclitaxel in terms of PFS and response rates and it has shown to have a good safety profile in KS patients.

18 February 2021 in Bosnian Journal of Basic Medical Sciences
Verified
Journal Article
Open access
PDF file
BOBirol Ocak
Birol Ocak
FAFatma Öz Atalay
Fatma Öz Atalay
AŞAhmet Bilgehan Bilgehan Şahin
Ahmet Bilgehan Bilgehan Şahin
MOMine Ozsen
Mine Ozsen
BDBahar Dakiki
Bahar Dakiki
TETürkkan Evrensel
Türkkan Evrensel
Endometrial endometrioid carcinoma (EEC) represents approximately 75–80% of endometrial carcinoma cases. Three hundred thirty-six patients with EEC followed-up in the authors’ medical center between and 2010–2018 were included in our study. Two hundred 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, 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.

28 February 2022 in Ginekologia Polska
Verified
Journal Article
Closed access
PDF file
BOBirol Ocak
Birol Ocak
ASAhmet Bilgehan Sahin
Ahmet Bilgehan Sahin
FAFatma Oz Atalay
Fatma Oz Atalay
MOMine Ozsen
Mine Ozsen
BDBahar Dakiki
Bahar Dakiki
TETurkkan Evrensel
Turkkan Evrensel
Objectives: 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 ECC, 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. Objectives: 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 ECC, 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.

21 February 2022 in Journal of Oncology Pharmacy Practice
Verified
Journal Article
Closed access
BCBurcu Caner
Burcu Caner
HEHulya Ertas
Hulya Ertas
BOBirol Ocak
Birol Ocak
ECErdem Cubukcu
Erdem Cubukcu
Introduction: Hyperprogression is a specific type of response seen with immunotherapy that is observed in all malignancies with a frequency of 9% - 29%, characterized by a rapid increase in tumor burden. Many possible related factors and possible markers have been evaluated but a clinical or laboratory parameter associated with hyperprogression has not yet been established. For renal cell carcinoma, hypercalcemia is known to be a poor prognostic factor but it has not been linked to hyperprogression. Case report: We retrospectively evaluated 52 patients diagnosed with renal cell carcinoma who had nivolumab treatment in any line. 3 of 9 patients who had hyperprogression were noticed to have hypercalcemia preceding hyperprogression. Here we present those 3 cases who developed hypercalcemia after nivolumab and had hyperprogression at follow-up. Management and outcome: All cases had less than 4 courses of nivolumab and showed hyperprogression in assessment. Nivolumab was discontinued. However, patients’ survival was extremely poor, as expected. Discussion: The development of hypercalcemia may help predict hyperprogression in patients with renal cell carcinoma who receive immunotherapy. In such cases, early evaluation of progression and cessation of nivolumab may be considered.

18 October 2024 in Journal of Clinical Medicine
Verified
Journal Article
Open access
PDF file
TOTuğba OCAK
Tuğba OCAK
BYBurcu Yagiz
Burcu Yagiz
BOBirol Ocak
Birol Ocak
ÖYÖzge Yoğurtçu
Özge Yoğurtçu
FBFatma Başıbüyük
Fatma Başıbüyük
YPYavuz Pehlivan
Yavuz Pehlivan
Background: Secukinumab is a monoclonal antibody against interleukin 17 approved for patients with axial spondyloarthritis (axSpA), psoriatic arthritis (PsA), and psoriasis. Treating axSpA and PsA patients with a history of malignancy is a challenge. While initial results on the applicability of secukinumab in this patient group are positive, the number of studies on this topic remains limited. This study aimed to investigate the drug’s survival time and the efficacy and safety of secukinumab treatment in this specific patient group. Methods: This retrospective study included 30 patients with a history of malignancy who were followed up in rheumatology outpatient clinics in 12 centers throughout Turkey and treated with secukinumab between May 2018 and March 2024 with a diagnosis of axSpA and PsA. Results: The mean follow-up time was 29.8 ± 19.3 months. The drug retention rate was 89.7% after 12 months and 80.6% after 24 months. The most common tumor in our study was papillary thyroid carcinoma (n = 5, 16.7%). During follow-up, local tumor recurrence was observed in a patient with urothelial carcinoma of the bladder. Conclusions: In the largest cohort reported to date, treatment with secukinumab in axSpA and PsA patients with a history of malignancy was not shown to cause oncologic recurrence except for one local tumor recurrence. Drug retention rates were also high, and disease activation and function improved compared to baseline. Therefore, secukinumab could be a safe and effective option for this patient group.