Determinants of treatment in patients with stage IV renal cell carcinoma

BACKGROUND: Advances in systemic targeted therapies afford treatment opportunities in patients with metastatic renal cell carcinoma (RCC). Elderly patients with metastatic RCC present a subpopulation for consideration owing to competing causes of mortality and benefits seen with new therapeutic agents. We investigate treatment patterns for elderly patients with stage IV RCC and determine factors associated with not receiving treatment. METHODS: The Surveillance Epidemiology and End Results (SEER) Medicare linked data set contained 949 stage IV RCC patients over age 65 diagnosed between 2007 and 2011. Treatment approach was modeled using multinomial logistic regression. Landmark analysis at 6 months accounted for early death as a potential explanation for no treatment. RESULTS: Of the 949 patients with stage IV RCC, 26.2% received surgery and 34.1% received systemic therapy within 6 months of diagnosis. Among our entire cohort, over half (51.2%) had no evidence of receiving surgery or systemic therapy. Among the 447 patients who survived at least 6 months, 26.6% did not receive treatment during this time. Older patients and those with a higher Charlson Comorbidity Index (CCI) had lower odds of being treated with surgery, systemic therapy, or both. Conversely, married patients had higher odds of receiving these therapies. These associations were largely sustained in the 6-month landmark analyses. CONCLUSIONS: Elderly patients with metastatic RCC present a unique subpopulation for consideration owing to competing causes of mortality. Many elderly patients with stage IV RCC did not receive surgery or systemic therapy up to 6 months from diagnosis. Several clinical and demographic factors were associated with this observation. Further investigation is needed to understand the rationale underlying the underutilization of systemic therapy in elderly patients.