[Statistical analysis of tumors of the renal pelvis and the ureter--determinants of prognostic significance].

Sixty-two patients with epithelial tumors of the renal pelvis and the ureter were studied with respect to 16 clinicopathological factors and their relationship to the patients survival. The cumulative survival curves are depicted by the Kaplan-Meier method and the statistical difference in the survival rates were detected in 11 factors, age, tumor number, multicentricity, tumor size, histological tumor type, stage, grade, growth pattern, infiltration pattern, lymphatic invasion and venous invasion. Cox's proportional hazard model was applied to evaluate the contribution of these 11 factors to survival. With the univariate analysis, lymphatic invasion showed the greatest hazard ratio followed by growth pattern, stage, venous invasion, age, and grade in this order. Stepwise selection of these factors based on the relative magnitude of their contribution to the survival with Cox's proportional hazard model revealed the most important factor for survival as the lymphatic invasion (hazard ratio 5.29), followed by growth pattern (hazard ratio 2.89). In conclusion, patients with tumor lymphatic invasion and tumor of non-papillary growth pattern showed poor prognosis, and adjuvant chemotherapy should be performed on them to improve their survival.