Prognostic impact of non-urothelial carcinoma of the upper urinary tract: Analysis of hospital-based cancer registry data in Japan.

Abstract

To identify the prognosis of patients with non-urothelial carcinoma of the upper urinary tract and compare it with that of patients with urothelial carcinoma. We used hospital-based cancer registry data in Japan to extract histologically confirmed non-urothelial carcinoma and urothelial carcinoma cases of the upper urinary tract diagnosed in 2008-2009. We estimated the 5-year overall survival by a Kaplan-Meier analysis. The Cox proportional hazards regression analysis was used to evaluate prognostic factors. A total of 2567 upper urinary tract cancer patients with confirmed histological subtypes were identified. The most common histology of non-urothelial carcinoma was squamous cell carcinoma (n=88, 3.4%) followed by adenocarcinoma (n=33, 1.3%) and small cell carcinoma (n=10, 0.4%). The proportion of advanced stage in the squamous cell carcinoma patients was significantly higher than that in the urothelial carcinoma patients (P=0.003). In stageIV, the proportion of patients who received a combination of surgery+chemotherapy in the urothelial carcinoma group was higher than that in the non-urothelial carcinoma group (34% vs 16%, respectively). The 5-year overall survival rates of the non-urothelial carcinoma patients at stagesI-III and stageIV were significantly worse than those of the urothelial carcinoma patients (P=0.003, P<0.001, respectively). In multivariate analyses, age ≥73years, advanced stage (stageIV), tumor location (ureter) and the presence of non-urothelial carcinoma histology were independent poor prognosis factors. The prognosis of non-urothelial carcinoma patients is worse than that of urothelial carcinoma patients, especially for non-urothelial carcinoma patients at stageIV. More effective systemic therapies are required to improve these patients' oncological outcomes.