Impact of Metastasectomy on Cancer Specific and Overall Survival in Metastatic Renal Cell Carcinoma: Analysis of the REMARCC Registry.

BACKGROUND

Treatment paradigms for management of metastatic renal cell carcinoma (mRCC) are evolving. We examined impact of surgical metastasectomy on survival across in mRCC stratified by risk-group.

METHODS

Multicenter retrospective analysis from the Registry of Metastatic RCC database. The cohort was subdivided utilizing Motzer criteria (favorable-, intermediate-, high-risk). Primary outcome was all-cause mortality (ACM)/overall survival (OS); secondary outcome was cancer-specific mortality (CSM)/cancer-specific survival (CSS). Impact of metastasectomy was analyzed via Cox-Regression analysis adjusting for potential prognostic variables and Kaplan-Meier analysis (KMA) within each risk-group.

RESULTS

Four hundred thirty-one patients (59 favorable-risk, 274 intermediate-risk, 98 high-risk; median follow-up 27.2 months) were analyzed. Metastasectomy was performed in 22 (37%), 66 (24%), and 32 (16%) of favorable-, intermediate- and high-risk groups (P = .012). Median number of metastases at diagnosis differed significantly (favorable-risk 2, intermediate-risk 3.4, high-risk 5.1, P < .001). On Cox-regression, high-risk (HR = 1.72, P = .002) was associated with worsened ACM, while metastasectomy was associated with improved ACM (HR = 0.56, P = .005). On KMA, median OS (months) was longer with metastasectomy in favorable- (92.7 vs. 25.8, P = .003) and intermediate-risk (26.3 vs. 20.1, P = .038), but not high-risk (P = .911) groups. Metastasectomy was associated with longer CSS in favorable- (76.1 vs. 32.8, P = .004) but not intermediate- (P = .06) and high-risk (P = .595) groups.

CONCLUSIONS

Metastasectomy was independently associated with improved ACM and CSM, as well as improved CSS and OS in favorable- and intermediate-risk mRCC patients. Metastasectomy may be considered as component of multimodal management strategy in favorable and intermediate-risk subgroups. In high-risk patients, metastasectomy should be deferred except in select circumstances.