Görkem Köymen

Dr. Görkem Köymen

orcid

Research Focus & Metrics

Academic Career Length

5Years (2022-Present)

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

Representative Publications

View All Publications
22 February 2026 in Journal of Clinical Medicine
Verified
Journal Article
Open access
PDF file
BKBaris Koksal
Baris Koksal
HYHasan Çağrı Yıldırım
Hasan Çağrı Yıldırım
DGDeniz Can Guven
Deniz Can Guven
FKFatih Köse
Fatih Köse
GKGörkem Köymen
Görkem Köymen
ZAZafer ARIK
Zafer ARIK
Background: Poly(ADP-ribose) polymerase (PARP) inhibitors have been established as a first-line maintenance therapy in advanced epithelial ovarian cancer (EOC) following platinum-based chemotherapy. While phase III trials have demonstrated significant progression-free survival (PFS) benefits with olaparib and niraparib, real-world data remain limited. Methods: This retrospective, multicenter real-world study included 179 patients with newly diagnosed epithelial ovarian treated with first-line maintenance olaparib or niraparib across 33 centers in Türkiye between January 2014 and March 2025. Clinical, pathological, and molecular data—including BRCA (Breast Cancer Susceptibility Gene) mutation status, origin, and variant classification—was collected. The primary endpoint was PFS, and secondary endpoints included overall survival (OS) and safety. Survival outcomes were analyzed using Kaplan–Meier methods. Results: Of 179 patients, 110 received olaparib and 69 received niraparib. BRCA mutations were present in 88.3% of patients, while 11.7% had unknown HRD status. Median follow-up was 16.5 months, and median PFS was not reached. Estimated PFS rates for the overall cohort were 91.0% at 6 months, 83.0% at 12 months, and 64.0% at 24 months. In the olaparib cohort, BRCA-mutant patients demonstrated PFS rates of 89%, 78%, 73%, and 64% at 6, 12, 18, and 24 months, respectively. In the niraparib cohort, corresponding PFS rates among BRCA-mutant patients were 87% at 6 months and 75% at 12 months. Patients harboring pathogenic BRCA variants experienced longer PFS compared with those with likely pathogenic variants. Any-grade adverse events occurred in 73.7% of patients, and grade 3–4 events in 29.6%, with hematologic toxicities predominating. Dose interruptions were more frequent with niraparib, while treatment discontinuation rates were low in both groups. No cases of myelodysplastic syndrome or acute myeloid leukemia were observed. Conclusions: In this large multicenter real-world cohort, first-line maintenance therapy with olaparib and niraparib provided durable PFS benefit in patients with advanced EOC, particularly among those with pathogenic BRCA mutations, confirming their effectiveness and manageable safety profiles in routine clinical practice.

1 July 2022 in Experimental and Clinical Transplantation
Verified
Journal Article
Closed access
GKGörkem Köymen
Görkem Köymen
ACAygul Celtik
Aygul Celtik
ACAkin Cinkooglu
Akin Cinkooglu
STSeray Toz
Seray Toz
GAGulay Asci
Gulay Asci
MEMunevver Erdinc
Munevver Erdinc
Pneumocystis jirovecii pneumonia is an opportunistic infection in kidney transplant recipients. It may be complicated by hypercalcemia. Here, we discuss a 59-year-old man who presented with respiratory symptoms and hypercalcemia. He had undergone a deceased donor kidney transplant 2 years previously. The patient had persistent hyperparathyroidism, but his serum calcium level was normal. At the time of admission, his serum calcium level had increased and his parathyroid hormone level was suppressed. He was diagnosed with Pneumocystis jirovecii pneumonia. Serum calcium and parathyroid hormone levels returned to baseline values after treatment. Pneumocystis jirovecii pneumonia is an important infection that can present with hypercalcemia among kidney transplant recipients.