Factors associated with the survival of patients with primary small cell carcinoma of the kidney

Background: Primary small cell carcinoma (SCC) of the kidney is rare, and the factors associated with the survival of these patients are yet to be elucidated. Patients and methods: We collected data on patients who were admitted to our hospital for SCC of the kidney in the last 22 years and of those in studies in the literature. Clinical characteristics were summarized using descriptive statistics. The associations of these factors with survival were evaluated using Cox regression models, and the hazard ratio of death was calculated. Results: This study included 45 patients (8 admitted to our hospital and 37 from studies in the literature) with SCC of the kidney. The overall median survival time was 9.9 months (range 6.9-31.6). Data on demographics, clinical symptoms, tumor staging, and tumor characteristics recorded at the time of diagnosis were not associated with survival. Among the different treatment modalities applied, cisplatin-based chemotherapy afforded a strong survival advantage (hazard ratio = 0.35, p = 0.022). However, patients with early local recurrence (hazard ratio = 19.13, p = 0.012) and early distant metastasis (hazard ratio = 10.93, p = 0.003) after primary treatment showed significantly poor survival. Conclusions: Patients with primary SCC of the kidney generally presented with large, advanced-stage tumors and showed poor survival. Early detection of the tumor, use of cisplatin-based chemotherapy, and careful follow-up for local recurrence or frequent metastasis within 6 months after the primary treatment could be important for improving overall patient survival.