Trends in Initial Systemic Therapy for Elderly Patients with Metastatic Clear Cell Renal Cell Carcinoma.

Background: The treatment landscape for metastatic clear cell renal cell carcinoma (mRCC) is rapidly changing. It is unknown how adoption of new types of therapies may differ by patient age.

Objective: To compare trends in first-line therapy use for older (≥70 years) and younger (< 70) patients with mRCC before and after approval of nivolumab in 2015.

Methods: Using the National Cancer Database, we assessed trends in first-line therapy use by calculating the proportion of patients receiving targeted therapy, immunotherapy, or no systemic therapy by year of diagnosis. Initial systemic treatment was compared for patients diagnosed in 2016 with patients diagnosed in 2011 as a control group prior to nivolumab approval. Multivariable regression analysis was used to evaluate the interaction between year of diagnosis and elderly status for use of first-line immunotherapy or targeted therapy.

Results: From 2006 to 2016, the proportion of patients receiving any type of systemic therapy increased from 43.7% to 56.5%. On stratified multivariable regression analysis, older patients diagnosed in 2016 were 17.3 times more likely to receive first-line immunotherapy compared to those diagnosed in 2011, while younger patients were 2.3 times more likely. There was no change in targeted therapy use over this time regardless of patient age.

Conclusions: The rate of adoption of first-line immunotherapy was particularly pronounced for elderly compared to younger patients. While first-line use of immunotherapy may have allowed elderly patients to receive systemic therapy that they otherwise would not, the efficacy of these drugs in elderly patients deserves further study.