Gonca Çoban
Başkent University
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Publication
Featured researches published by Gonca Çoban.
Journal of The Turkish German Gynecological Association | 2015
Erhan Şimşek; Esra Bulgan Kilicdag; Pinar Caglar Aytac; Gonca Çoban; Seda Yüksel Şimşek; Tayfun Cok; Bulent Haydardedeoglu
OBJECTIVE Luteal phase is defective in in vitro fertilization (IVF) cycles, and many regimens were tried for the very best luteal phase support (LPS). Gonadotropin releasing hormone (GnRH) agonist use, which was administered as an adjunct to the luteal phase support in IVF cycles, was suggested to improve pregnancy outcome measures in certain randomized studies. We analyzed the effects of addition of GnRH agonist to standard progesterone luteal support on pregnancy outcome measures, particularly the live birth rates. MATERIAL AND METHODS This is a retrospective cohort study, including 2739 IVF cycles. Long GnRH agonist and antagonist stimulation IVF cycles with cleavage-stage embryo transfer were included. Cycles were divided into two groups: Group A included cycles with single-dose GnRH agonist plus progesterone LPS and Group B included progesterone only LPS. Live birth rates were the primary outcome measures of the analysis. Miscarriage rates and multiple pregnancy rates were the secondary outcome measures. RESULTS Live birth rates were not statistically different in GnRH agonist plus progesterone (Group A) and progesterone only (Group B) groups in both the long agonist and antagonist stimulation arms (40.8%/41.2% and 32.8%/34.4%, p<0.05 respectively). Moreover, pregnancy rates, implantation rates, and miscarriage rates were found to be similar between groups. Multiple pregnancy rates in antagonist cycles were significantly higher in Group A than those in Group B (12.0% and 6.9%, respectively). CONCLUSION A beneficial effect of a single dose of GnRH agonist administration as a luteal phase supporting agent is yet to be determined because of the wide heterogeneity of data present in literature. Well-designed randomized clinical studies are required to clarify any effect of luteal GnRH agonist addition on pregnancy outcome measures with different doses, timing, and administration routes of GnRH agonists.
Archives of Gynecology and Obstetrics | 2009
Polat Dursun; Ali Ayhan; N. Cagla Tarhan; Gonca Çoban; Esra Kuscu
IntroductionBrain metastasis is rarely seen in gynecologic cancers. It is more rarely encountered in vulvar carcinoma.Case historyA 56-year-old postmenopausal women referred our gynecologic oncology unit for the treatment of locally advanced vulvar carcinoma. Twenty-five days after the operation she developed vertigo and nistagmus. Cranial MRI investigation revealed that she had multiple cerebellar metastasis.ConclusionBrain metastasis might be seen in patient with vulvar carcinoma. To the best of our knowledge, this is the first reported case of vulvar carcinoma which developed cerebellar metastasis.
Journal of Gynecologic Oncology | 2017
Nazlı Topfedaisi Ozkan; Mehmet Mutlu Meydanli; Mustafa Erkan Sarı; Fuat Demirkiran; Ilker Kahramanoglu; Tugan Bese; Macit Arvas; Hanifi Şahin; Ali Haberal; Husnu Celik; Gonca Çoban; Tufan Oge; Omer T. Yalcin; Ozgur Akbayir; Baki Erdem; Ceyhun Numanoglu; Nejat Ozgul; Gokhan Boyraz; Mehmet Coskun Salman; Kunter Yuce; Murat Dede; Müfit Cemal Yenen; Salih Taşkın; Duygun Altın; Uğur Fırat Ortaç; Hülya Ayık; Tayup Şimşek; Tayfun Gungor; Kemal Güngördük; Muzaffer Sancı
Objective To determine factors influencing overall survival following recurrence (OSFR) in women with low-risk endometrial cancer (EC) treated with surgery alone. Methods A multicenter, retrospective department database review was performed to identify patients with recurrent “low-risk EC” (patients having less than 50% myometrial invasion [MMI] with grade 1 or 2 endometrioid EC) at 10 gynecologic oncology centers in Turkey. Demographic, clinicopathological, and survival data were collected. Results We identified 67 patients who developed recurrence of their EC after initially being diagnosed and treated for low-risk EC. For the entire study cohort, the median time to recurrence (TTR) was 23 months (95% confidence interval [CI]=11.5–34.5; standard error [SE]=5.8) and the median OSFR was 59 months (95% CI=12.7–105.2; SE=23.5). We observed 32 (47.8%) isolated vaginal recurrences, 6 (9%) nodal failures, 19 (28.4%) peritoneal failures, and 10 (14.9%) hematogenous disseminations. Overall, 45 relapses (67.2%) were loco-regional whereas 22 (32.8%) were extrapelvic. According to the Gynecologic Oncology Group (GOG) Trial-99, 7 (10.4%) out of 67 women with recurrent low-risk EC were qualified as high-intermediate risk (HIR). The 5-year OSFR rate was significantly higher for patients with TTR ≥36 months compared to those with TTR <36 months (74.3% compared to 33%, p=0.001). On multivariate analysis for OSFR, TTR <36 months (hazard ratio [HR]=8.46; 95% CI=1.65–43.36; p=0.010) and presence of HIR criteria (HR=4.62; 95% CI=1.69–12.58; p=0.003) were significant predictors. Conclusion Low-risk EC patients recurring earlier than 36 months and those carrying HIR criteria seem more likely to succumb to their tumors after recurrence.
Journal of Obstetrics and Gynaecology Research | 2018
Halis Özdemir; Hakan Kalaycı; Selçuk Yetkinel; Tayfun Cok; Gonca Çoban; Ebru Tarim
We aimed to define the normal values of second‐trimester fetal prenasal thickness and nasal bone length ratio (PNT/NBL) in a low‐risk Turkish population and investigate the relationship between the increased PNT and nuchal fold (NF).
Journal of Gynecologic Oncology | 2018
Ali Ayhan; Nazlı Topfedaisi Ozkan; Murat Oz; Gunsu Kimyon Comert; Zeliha Firat Cuylan; Gonca Çoban; Osman Turkmen; Baki Erdem; Hanifi Şahin; Ozgur Akbayir; Murat Dede; Ahmet Taner Turan; Husnu Celik; Tayfun Gungor; Ali Haberal; Macit Arvas; Mehmet Mutlu Meydanli
Objective The purpose of this study was to investigate the prognostic value of lymph node ratio (LNR) in women with stage IIIC endometrioid endometrial cancer (EC). Methods A multicenter, retrospective department database review was performed to identify patients with stage IIIC pure endometrioid EC at 6 gynecologic oncology centers in Turkey. A total of 207 women were included. LNR, defined as the percentage of positive lymph nodes (LNs) to total nodes recovered, was stratified into 2 groups: LNR1 (≤0.15), and LNR2 (>0.15). Kaplan-Meier method was used to generate survival data. Factors predictive of outcome were analyzed using Cox proportional hazards models. Results One hundred and one (48.8%) were classified as stage IIIC1 and 106 (51.2%) as stage IIIC2. The median age at diagnosis was 58 (range, 30–82) and the median duration of follow-up was 40 months (range, 1–228 months). There were 167 (80.7%) women with LNR ≤0.15, and 40 (19.3%) women with LNR >0.15. The 5-year progression-free survival (PFS) rates for LNR ≤0.15 and LNR >0.15 were 76.1%, and 58.5%, respectively (p=0.045). An increased LNR was associated with a decrease in 5-year overall survival (OS) from 87.0% for LNR ≤0.15 to 62.3% for LNR >0.15 (p=0.005). LNR >0.15 was found to be an independent prognostic factor for both PFS (hazard ratio [HR]=2.05; 95% confidence interval [CI]=1.07–3.93; p=0.03) and OS (HR=3.35; 95% CI=1.57–7.19; p=0.002). Conclusion LNR seems to be an independent prognostic factor for decreased PFS and OS in stage IIIC pure endometrioid EC.
Journal of Obstetrics and Gynaecology | 2017
Elif Didem Özdemir; Cem Yalcinkaya; Gonca Çoban; Tuba Canpolat; Aylin Okçu Heper; Husnu Celik
Blue naevi (BN) are rare benign pigmented lesions originating from the dermal melanocytes. BN and their variants are classified as cellular blue naevus (CBN), atypical cellular blue naevus (ACBN) and malignant blue naevus (melanoma arising in BN) according to histological features. ACBN is extremely rare and it was reported to appear in oral mucosa, vertex, scalp and buttocks (Barnhill et al. 2008). To the best of our knowledge, this is the first description of an atypical cellular blue naevus of clitoris.
Gynecological Endocrinology | 2016
Pinar Caglar Aytac; Esra Bulgan Kilicdag; Bulent Haydardedeoglu; Erhan Simsek; Tayfun Cok; Gonca Çoban
Abstract Objective: To evaluate the effect of luteal phase support (LPS) using progesterone vaginal gel on pregnancy rate (PR) and live birth rate (LBR) during cycles in which controlled ovarian stimulation (COH) was performed using gonadotropins with intrauterine insemination (IUI) cycles in patients with unexplained infertility and polycystic ovarian syndrome. Materials and methods: From 2010 to 2015, all IUI cycles in which COH was performed using gonadotropins were evaluated retrospectively. LPS was not used until July 2013, after which vaginal progesterone gel was applied in the luteal phase of IUI cycles. Both groups of patients were evaluated in terms of the effect of LPS on PR and LBR. Results: In total, 1578 IUI cycles were evaluated, of which 481 were LPS (+) and 1097 LPS (−). PR and LBR per cycle were 10.6% and 7.4%, respectively, in the LPS (+) group, and 11.6% and 7.7%, respectively, in the LPS (−) group (p = 0.31 and p = 0.25). PR and LBR per patient were 17% and 12%, respectively, in the LPS (+) group, and 17.4% and 12.3%, respectively, in the LPS (−) group (p = 0.48 and p = 0.82). Conclusions: We found no difference in PR and LBR per cycle and per patient according to the use of LPS in IUI cycles in which COH was performed using gonadotropins. Thus, routine use of LPS in gonadotropin-stimulated cycles requires further research involving larger numbers of patients.
Journal of Ovarian Research | 2018
Hanifi Sahin; Mehmet Mutlu Meydanli; Mustafa Erkan Sarı; Ibrahim Yalcin; Gonca Çoban; Nazlı Topfedaisi Ozkan; Zeliha Firat Cuylan; Baki Erdem; Kemal Güngördük; Ozgur Akbayir; Murat Dede; Mustafa Coşkun Salman; Tayfun Gungor; Ali Ayhan
Archives of Gynecology and Obstetrics | 2018
Hanifi Sahin; Mustafa Erkan Sarı; Zeliha Firat Cuylan; Asuman Nihan Haberal; Levent Sirvan; Gonca Çoban; Ibrahim Yalcin; Tayfun Gungor; Husnu Celik; Mehmet Mutlu Meydanli; Ali Ayhan
Turkiye Klinikleri Gynecology Obstetrics - Special Topics | 2015
Gonca Çoban; Husnu Celik