Nedim Turan

Objective: Thymic epithelial tumors (TETs), including thymomas and thymic carcinomas, are rare mediastinal cancers with distinct prognoses, and long-term real-world data on survival and prognostic factors remain limited. Methods: In this retrospective single-center study, 42 patients diagnosed between 2006 and 2024 were analyzed. Data on clinicopathological features, treatments, and survival were obtained from records. Survival was assessed using the Kaplan–Meier method with the log-rank test, and prognostic factors were evaluated using univariable Cox proportional hazards regression analysis. Results: The median follow-up duration was 38 months (range, 2-197 months). The median age at diagnosis was 52 years. Thymoma accounted for 81% of cases and thymic carcinoma for 19%. Complete resection (R0) was achieved in 67.7% of operated patients and was strongly associated with better survival, with a 5-year overall survival (OS) of 94% compared to 33% in incompletely resected tumors. De novo metastatic disease (hazards ratio [HR] = 15.3; 95% CI: 3.39-69.20) and R2 resection (HR = 8.64; 95% CI: 2.65-28.18) were significantly associated with poorer OS. No statistically significant difference in survival was observed between patients who received mediastinal radiotherapy and those who did not. Conclusions: Complete resection remains the cornerstone of survival in TETs. Metastatic and incomplete resection are associated with poor outcomes. No statistically significant difference in survival was observed between patients who received mediastinal radiotherapy and those who did not. These findings provide real-world evidence to guide clinical management of these rare malignancies. Cite this article as: Türkoğlu E, Işık D, Buser NS, et al. Prognostic factors and survival in thymoma and thymic carcinoma: a retrospective cohort study. Cerrahpaşa Med J 2026, 50, 0089, doi: 10.5152/cjm.2026.26089.

Background: The optimal use of chemotherapy rechallenge in later-line metastatic colorectal cancer (mCRC) remains uncertain. We compared third-line FOLFOX plus bevacizumab rechallenge with regorafenib and examined whether the oxaliplatin-free interval was associated with treatment outcomes. Methods: This retrospective single-center study included 122 patients with metastatic left-sided, RAS (KRAS/NRAS) and BRAF wild-type, proficient mismatch repair (pMMR) colorectal adenocarcinoma treated between 2018 and 2025. All patients had received first-line FOLFOX plus cetuximab or panitumumab, followed by FOLFIRI plus bevacizumab after progression. In the third-line setting, 65 patients received FOLFOX plus bevacizumab as oxaliplatin rechallenge and 57 received regorafenib. The primary endpoint was progression-free survival (PFS). Cox regression, propensity score-based inverse probability of treatment weighting (IPTW), and treatment-by-oxaliplatin-free interval interaction analyses were performed. Results: Median third-line PFS was 7.33 months with FOLFOX plus bevacizumab rechallenge and 6.17 months with regorafenib (log-rank p < 0.001). FOLFOX plus bevacizumab rechallenge was associated with a lower hazard of progression in multivariable analysis (adjusted HR, 0.58; 95% CI, 0.39–0.88; p = 0.009), with consistent results in the propensity score-based IPTW sensitivity analysis (HR, 0.58; 95% CI, 0.40–0.86; p = 0.006). Restricted cubic spline analysis indicated a nonlinear association between OFI and PFS (p for nonlinearity = 0.005), while flexible modeling did not provide robust evidence of a treatment-by-OFI interaction (global p = 0.806). In exploratory subgroup analyses, FOLFOX plus bevacizumab rechallenge was associated with longer PFS than regorafenib among patients with an OFI of ≥6 months (adjusted HR, 0.39; 95% CI, 0.24–0.65; p < 0.001), whereas no significant difference was observed among those with an OFI of p = 0.199). Conclusions: FOLFOX plus bevacizumab rechallenge was associated with longer third-line PFS than regorafenib in this selected and uniformly treated mCRC cohort. OFI was associated with PFS in a nonlinear manner, but there was no robust evidence that it modified the relative treatment effect across its continuous range. Exploratory subgroup findings based on a 6-month cutoff require external validation.

Background: Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related mortality worldwide. Although the STRIDE regimen (durvalumab plus tremelimumab) has demonstrated an overall survival benefit in clinical trials, real-world evidence remains limited, particularly in Turkish clinical practice. This study aimed to evaluate the effectiveness and safety of first-line STRIDE therapy in patients with unresectable HCC treated in routine clinical practice. Methods: We conducted a retrospective multicenter study including patients with unresectable HCC who received first-line durvalumab plus tremelimumab through the Turkish national Early Access Program across 18 oncology centers. Progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan–Meier method, and exploratory Cox regression analyses were performed to evaluate baseline prognostic factors. Results: Thirty-two patients were included. The median PFS was 7.25 months (95% CI, 3.68–22.29), and the median OS was 11.43 months (95% CI, 4.50–not reached). The underlying liver disease etiology was non-viral in 53.1% of patients, hepatitis B virus in 40.6%, and hepatitis C virus in 6.3%. Grade ≥ 3 treatment-related adverse events occurred in fewer than 10% of patients. Conclusions: In this multicenter real-world cohort, first-line durvalumab plus tremelimumab appeared to be a feasible treatment option and was generally well tolerated in patients with unresectable HCC. However, given the retrospective design, small sample size, and absence of a control group, these findings should be interpreted cautiously and require confirmation in larger prospective comparative studies.

Objective: Metastatic gastric cancer is a biologically heterogeneous disease with a poor prognosis. Although the presence of distant metastasis defines advanced disease, the prognostic impact of specific metastatic patterns remains unclear. This study aimed to evaluate the association between metastatic patterns and overall survival in patients with metastatic gastric cancer. Methods: In this retrospective single-centre study, 292 patients with histopathologically confirmed metastatic gastric cancer were included. Metastatic sites were evaluated using computed tomography, magnetic resonance imaging, and/or positron emission tomography. Overall survival (OS) was analysed using the Kaplan–Meier method and compared using the log-rank test. Prognostic factors were assessed through univariate and multivariate Cox proportional hazards regression models. Results: The median OS for the entire cohort was 10 months (95% CI, 9.3–12.0). The most common sites of metastasis were non-regional lymph nodes (78.8%), liver (49.7%), and peritoneum (30.8%). Peritoneal metastasis was associated with significantly worse survival in unadjusted Kaplan–Meier analysis (9.5 vs 11 months, P<0.001), whereas other metastatic sites were not significantly associated with OS. No significant difference in OS was observed between patients with single-site and multiple-site metastases (P=0.31). In multivariate analysis, Eastern Cooperative Oncology Group performance status (ECOG) and prior gastrectomy were identified as independent prognostic factors, while the impact of metastatic site did not remain statistically significant. Conclusion: Metastatic gastric cancer exhibits substantial heterogeneity in survival outcomes according to the distribution of metastatic sites. Peritoneal involvement was associated with worse survival in unadjusted analyses and may represent a clinically relevant marker of adverse prognosis. Including site-specific metastatic information in prognostic assessments may contribute to improved risk stratification in addition to the conventional staging system.

Backround:Hepatocellular carcinoma (HCC) is the most common neoplasm to cause death. First line treatment options are still challenging for HCC. STRIDE regimen (durvalumab/tremelimumab) showed improved median overall survival (OS) rates however did not make differ significantly in median progression-free survival (PFS) rate. Method:We reviewed outcomes of patients with HCC who initiated durval-umab/tremelimumab between 2020 and 2024, across 18 institutions. OS and PFS were analyzed using the Kaplan–Meier and Cox models, adjusting for baseline characteris-tics. Results: A total of 32 patients were included in the study. Median PFS was was 7,25 months (%95 confidence interval (CI) 3,68-22,29) and the median OS was 11,43 months (%95 CI 4,5-NA). Non-viral, HBV and HCV constituted to etiology was re-spectively %53,1, %40,6 and %6,3 of patients. Grade ≥ 3 advers events were found less than %10 of populations. Conclusions: This real world retrospective study showed that STRIDE regimen was effective and safety for HCC in first line.

The present study aimed to assess whether the baseline pan‑immune‑inflammation value (PIV), a readily available blood‑based marker, is linked to benefits from nivolumab treatment (response and survival) in patients with metastatic non‑small cell lung cancer (mNSCLC) receiving second‑line or later therapy. The data of 303 patients diagnosed with mNSCLC who received nivolumab at Kartal Dr Lütfi Kırdar City Hospital (Istanbul, Türkiye) between January 2022 and December 2023 were retrospectively reviewed. After excluding 33 ineligible cases, 270 patients were included in the final analysis. PIV was calculated from pre‑treatment peripheral blood counts. The median overall survival (OS) and progression‑free survival (PFS) times were assessed from the start of nivolumab treatment. Programmed death‑ligand 1 expression data were unavailable in this real‑world cohort, reflecting routine clinical practice. The median age was 63 years, and 84.1% of patients were male. The median OS and PFS times were 16 and 7 months, respectively. The patient responses were as follows: Progressive disease in 41.1%, partial response in 30.4%, stable disease in 22.2% and complete response in 6.3% of patients. Receiver operating characteristic analysis identified an optimal PIV cut‑off of 604.5 for predicting nivolumab response. Patients with low PIV values had significantly longer median OS (25 vs. 11 months) and PFS (9 vs. 5 months) times, and a lower rate of nivolumab resistance (38.7 vs. 61.3%; P<0.001). Baseline PIV was confirmed as a significant predictor of nivolumab response (specificity, 62.9%; sensitivity, 61.3%; P<0.001). Upon multivariate logistic regression analysis, high PIV, blood group B antigen, Eastern Cooperative Oncology Group performance status 2 and lack of response to prior chemotherapy were identified as independent predictors of nivolumab resistance. In this real‑world cohort, results were consistent with the known activity of nivolumab in previously treated mNSCLC. Baseline PIV was associated with treatment outcomes and may serve as a convenient, blood‑based marker to inform immunotherapy decision‑making. Further prospective validation is needed before routine clinical use.

Background and Objectives: Positron emission tomography with 18F-FDG (PET-CT) provides a quantitative measure of tumor metabolic activity through the maximum standardized uptake value (SUVmax) of lung tumors—a measure of metabolic activity that may have prognostic value in non-small cell lung cancer (NSCLC). This study evaluated whether preoperative tumor SUVmax predicts outcomes in resected NSCLC. Materials and Methods: This single-center retrospective study included 209 consecutive patients with resected NSCLC who had preoperative FDG PET-CT. SUVmax of the primary tumor was recorded, and patients were stratified into low- and high-SUVmax groups to evaluate survival outcomes. Results: Median age was 62 years and 77% were male. Histologic subtypes were adenocarcinoma (44%), squamous carcinoma (43%), and others (13%), with stage I–III distribution of 39.7%, 33.5%, and 26.8%, respectively. SUVmax demonstrated moderate discrimination for mortality (AUC = 0.652), with an optimal cutoff of 11.14. Patients with SUVmax ≥ 11.14 had significantly worse OS and DFS. However, on multivariate analysis, SUVmax was not an independent predictor of outcomes, while extracapsular invasion (OS) and adjuvant chemotherapy (DFS) remained significant. Conclusions: In this cohort of resected NSCLC, high preoperative SUVmax (≥11.14) was associated with more advanced tumor stage and worse OS/DFS but was not an independent prognostic factor after accounting for other variables. Tumor invasiveness and use of adjuvant therapy were stronger outcome predictors. Preoperative SUVmax may help identify high-risk patients when considered alongside established clinicopathologic factors.

Background: Antibiotic exposure has been shown to negatively affect immune checkpoint inhibitor (ICI) efficacy in several cancers, possibly by disrupting gut microbiota. It represents a potentially modifiable clinical factor that may influence immunotherapy efficacy in RCC. However, data on renal cell carcinoma (RCC) remain limited, especially regarding prognostic risk groups. Methods: We conducted a retrospective cohort study of 120 RCC patients treated with ICIs between 2018 and 2024 at Kartal Dr. Lütfi Kırdar City Hospital. Patients were classified based on systemic antibiotic exposure within ±30 days of ICI start. Survival outcomes were compared using Kaplan–Meier and Cox regression analyses. Subgroup analyses were performed according to the International Metastatic RCC Database Consortium (IMDC) risk classification. Results: Of the 120 patients, 38 (31.7%) received antibiotics during the peri-ICI period. Median progression-free survival (PFS) was significantly shorter in the antibiotic-exposed group (5.1 vs. 9.4 months; p = 0.004), as was overall survival (OS) (14.8 vs. 22.5 months; p = 0.03). Antibiotic use remained an independent predictor of both PFS (HR = 1.87; 95% CI: 1.21–2.89) and OS (HR = 1.64; 95% CI: 1.04–2.59). In subgroup analyses, intermediate-risk patients had worse OS with antibiotics (13.5 vs. 20.6 months; p = 0.035), as did poor-risk patients (8.1 vs. 13.9 months; p = 0.049). Conclusions: Antibiotic exposure during the peri-immunotherapy period is linked to significantly poorer outcomes in RCC patients, especially those with intermediate and poor IMDC risk scores. These findings emphasize the importance of antimicrobial stewardship and suggest a potential role for microbiome-informed patient management in RCC.

Background: Body mass index (BMI) has been widely investigated as a potential prognostic factor in breast cancer; however, its clinical relevance in patients with hormone receptor-positive/human epidermal growth factor receptor 2-negative (HR+/HER2−) metastatic breast cancer treated with CDK4/6 inhibitors remains controversial, particularly in contemporary real-world settings. This study aimed to evaluate the association between baseline BMI and clinical outcomes, including survival and treatment-related toxicity, in a real-world cohort. Methods: This single-centre retrospective observational cohort study included patients with HR+/HER2− metastatic breast cancer treated with endocrine therapy and a CDK4/6 inhibitor (palbociclib or ribociclib) in the metastatic setting between January 2018 and May 2025. Patients were categorised by baseline BMI (2). Progression-free survival (PFS) and overall survival (OS) were assessed using the Kaplan–Meier method and Cox proportional hazards models. To minimise confounding, propensity score matching (PSM) with a 1:3 nearest-neighbour algorithm was performed. Non-linear associations between continuous BMI and survival outcomes were explored using restricted cubic spline analyses. Treatment-related adverse events were evaluated according to CTCAE v5.0. Results: A total of 456 patients were included; 321 (70.4%) had a BMI ≥ 25 kg/m², and 135 (29.6%) had a BMI < 25 kg/m². Propensity score matching produced a balanced cohort of 220 patients. The reduction in sample size after matching reflects the need to achieve close baseline comparability between groups. In the matched cohort, no statistically significant differences in PFS (log-rank p = 0.55) or OS (log-rank p = 0.31) were observed across BMI categories. BMI was not an independent predictor of PFS or OS in multivariable analyses. However, restricted cubic spline modelling revealed a non-linear relationship between continuous BMI and survival outcomes, with increased risk at extreme BMI values, underscoring the limitations of dichotomous BMI categorisation. Conclusions: In this real-world cohort of patients with HR+/HER2− metastatic breast cancer treated with CDK4/6 inhibitors, dichotomised BMI categories were not independently associated with survival outcomes. However, modelling BMI as a continuous variable revealed a non-linear (U-shaped) relationship, with increased risk at both the low and high ends of the BMI distribution. These findings suggest that the prognostic impact of BMI is non-linear and may be obscured by simple dichotomous categorisation.

Objective: The role of adjuvant chemoradiotherapy (CRT) following curative gastrectomy remains controversial, especially in the context of D2 dissection. This research evaluated survival indicators through an analysis of previous observational studies and it evaluated treatment outcomes between patients who underwent CRT and those who received CT as their sole therapy. Methods: The researchers performed a non-randomized retrospective cohort study which analyzed 206 patients who underwent R0–R1 resection for gastric adenocarcinoma and received either adjuvant CRT (n = 107) or CT alone (n = 99). A Kaplan–Meier analysis together with Cox regression methods were used to evaluate survival outcomes of patients. Inverse probability of treatment weighting (IPTW) was applied to adjust for baseline differences between groups at the beginning of the study. The median follow-up was 52.0 months. Results: The baseline characteristics differed markedly between groups, with CRT patients showing higher rates of T4 tumors (34.6% vs. 22.2%), N3 disease (47.7% vs. 26.3%), vascular invasion (72.9% vs. 50.5%), and R1 resection (10.3% vs. 1.0%). Unadjusted survival favored CT alone (median DFS 81.7 vs. 103.9 months; median OS 86.2 months vs. not reached). These differences lost significance after IPTW adjustment (DFS: HR 1.18, p = 0.428; OS: HR 1.24, p = 0.336). T3–T4 stage, N2–N3 nodal status, vascular invasion, and positive margins emerged as independent prognostic factors. Subgroup analyses revealed no treatment interactions (all p > 0.05). Conclusions: The research used a retrospective study design which showed substantial differences between treatment groups at the beginning of the study. The survival results that showed better outcomes for CT alone became attenuated after the researchers applied propensity score adjustment to adjust for confounding from treatment selection. The study established that advanced T–N stage, vascular invasion, and positive margins were identified as independent prognostic factors. The research results are hypothesis-generating and require randomized controlled trials to establish the exact difference in effectiveness between different treatments.