Yasin AKTAŞ, Mücahit GELMİŞ
Meandros Medical and Dental Journal - 2026;27(3):403-413
Objective: Small cell carcinomas of the kidney (SCCK) and the upper urinary tract (SCC UUT) are exceedingly rare and aggressive malignancies. This study aimed to compare survival outcomes of these two conditions using a large population-based database. Materials and Methods: Data from the Surveillance, Epidemiology, and End Results (SEER) database (2000-2022) were analysed. Patients with histologically confirmed SCCK (n = 41) and SCC UUT (n = 54) were included. Clinicopathological variables and treatment modalities were evaluated. Cancer-specific survival (CSS) was estimated using the Kaplan-Meier method and Cox proportional hazards models were employed to identify independent prognostic factors. Results: The study cohort consisted of 95 patients. Patients with SCCK exhibited significantly higher rates of distant metastasis than the UUT group (58.5% vs. 40.7%, p = 0.029). The median CSS was 9 months for the UUT group and 6 months for the kidney group (p = 0.068). Multivariate analysis in the kidney group identified surgical intervention (HR: 0.18, p<0.001) and radiotherapy (HR: 0.35, p=0.020) as factors significantly associated with improved survival. Conversely, in the UUT group, distant stage and liver metastasis (HR: 3.94, p = 0.007) were significant predictors of poor prognosis. In the SCCK, lung metastasis was associated with poorer survival outcomes. Conclusion: SCCK and SCC UUT are characterised by early mortality and aggressive clinical courses. Survival in UUT tumours is largely determined by tumour stage and visceral metastasis. Surgical resection and radiotherapy were associated with prolonged survival in patients with kidney tumours. These findings suggest that site-specific, multimodal treatment strategies involving local control and systemic therapy may be beneficial.
