Surgical intervention in renal cell carcinoma patients with lung and bronchus metastasis is associated with longer survival time: a population-based analysis

BACKGROUND: As the most common metastasis site in renal cell carcinoma (RCC) patients, lung and bronchus metastasis (LBM) represents a late stage and a poor prognosis. The purpose of our study is to determine the impact of surgical intervention on prognosis of RCC patients with LBM by means of analysis the data from the Surveillance, Epidemiology and End Results (SEER) database. METHODS: test for the categorical variables. The survival analysis was estimated using the Kaplan-Meier (K-M) method and univariate comparison were performed using the log-rank test and unadjusted Cox proportional hazards regression models. Multivariate Cox proportional hazards regression survival models were adjusted. A second multivariate Cox proportional hazards regression survival model was created using the dataset after propensity score-matching approach (PSM). RESULTS: A total of 1,190 RCC patients with LBM were included, of whom 1,087 patients underwent surgery and 103 patients unperformed surgery. The median survival time was 56 months (95% CI, 54 to 59) for the surgery group, and 6 months (95% CI, 5 to 7) for non-surgery group. LBM patients underwent surgery had significantly longer survival time (log-rank test, P<0.001). In univariate analysis, the survival of RCC patients was significantly associated with surgery (P<0.001), grade II (P=0.014), grade III (P=0.001) and grade IV (P<0.001). Moreover, multivariate analysis indicated that surgery (P<0.001), grade II (P=0.018), grade III (P<0.001) and grade IV (P<0.001) were independent prognostic indexes for overall survival. Besides, in the subgroup of 1 years survival after diagnosis, longer survival times were seen in the surgery arms rather than non-surgery arms (P<0.001). In addition, longer survival times were observed in surgery arms in the subgroups of grade I, II, III and IV (all P<0.001). CONCLUSIONS: RCC patients with LBM who have surgical intervention might obtain a significantly longer survival time than non-surgical options. In consequence, surgery should be the preferred choice for eligible patients.