Prognostic Value of Site-Specific Metastases and Therapeutic Roles of Surgery and Chemotherapy for Patients With Metastatic Renal Pelvis Cancer: A SEER Based Study

BACKGROUND AND AIMS: There is a lack of research on metastatic renal pelvis cell carcinoma in the current literature. In this study, we aimed to detect distant metastatic patterns in renal pelvis cell carcinoma, and illustrated the affection of different metastatic sites, surgery to primary site and chemotherapy on prognosis outcomes in patients with diverse conditions. METHODS: We collected data between 2010 and 2015 from the Surveillance, Epidemiology and End Results database. Kaplan–Meier analysis with log-rank test was used for survival comparisons. Multivariate Cox regression model was employed to analyze the effect of distant metastatic sites on overall survival (OS) and cancer-specific survival (CSS). RESULTS: A total of 424 patients were included in the analysis, the median follow-up time was 5 months (interquartile range (IQR): 2-12) and 391 deaths (92.2%) in all patients were recorded. Among them, 192 (45.3%), 153 (36.1%), 137 (32.3%) and 127 (30.0%) patients were diagnosed with lung, bone, liver and brain metastases, respectively, while only 12 (2.8%) patients had brain metastases. The bi-organ, tri-organ and tetra-organ metastatic pattern was found in 135 (31.8%), 32 (7.5%) and 11 (2.6%) patients, respectively. The multivariate Cox analyses showed that distant lymph nodes (DL) metastases was not an independent prognostic factor for both OS and CSS (OS: Hazard ratios (HR) = 1.1, 95% CI = 0.8-1.4, P = 0.622; CSS: HR = 1.0, 95% CI = 0.8-1.3, P = 0.906). Besides, there was no significant difference of survival in patients with T3-T4 stage (OS: HR = 0.8, 95% CI = 0.5–1.2, P = 0.296; CSS: HR = 0.8, 95% CI = 0.5–1.2, P = 0.224), N2-3 stage (OS: HR = 0.8, 95% CI = 0.5–1.3, P = 0.351; CSS: HR = 0.7, 95% CI = 0.4–1.2, P = 0.259) and multi-organ metastases (OS: HR = 0.8, 95% CI = 0.5–1.3, P = 0.359; CSS: HR = 0.7, 95% CI = 0.4–1.2, P = 0.179) between surgery to primary site group and no-surgery to primary site group. CONCLUSION: we described the metastatic patterns of mRPCC and the prognosis outcomes of DL metastases, surgery to primary site and chemotherapy. Our findings provide more information for clinical therapeutic intervention and translational study designs.