Metastatic renal cell carcinoma: Patterns and predictors of metastases-A contemporary population-based series.

OBJECTIVE: To assess the patterns and predictors of metastatic disease in renal cell carcinoma (RCC) at the time of diagnosis in a contemporary series.

METHODS: The Surveillance, Epidemiology, and End Results database was queried for all patients with kidney RCC from 2010 to 2013 (N = 50,815). Distribution and predictors of distant metastases at diagnosis were assessed. Multivariate logistic regression hazard analyses were performed to determine covariates associated with the likelihood of having metastases at diagnosis, whereas competing risks regression analysis was used to assess predictors of cancer-specific mortality (CSM) in patients with metastatic disease.

RESULTS: Lung (7.73%) and bone (5.17%) metastases were the most common. The strongest predictors of metastatic disease were disease-specific factors, such as clinical T-stage (cT4 vs. cT1; odds ratio = 43.08; P<0.01) and higher Fuhrman grade (FG4 vs. FG1; odds ratio = 5.09; P<0.01). Papillary RCC and chromophobe RCC were associated with localized disease at the time of diagnosis. For CSM, the presence of brain and liver metastases were associated with worse CSM than lung or bone metastases. Although patient factors did not contribute to the presence of metastases at diagnosis, lower socioeconomic status and being widowed/divorced predicted worse CSM.

CONCLUSION: Understanding the distribution of distant metastases and associated CSM is important to counseling patients with newly diagnosed metastatic RCC. Although pathologic factors drive the presence of metastases at diagnosis, health care deficits in treatment remain.