Duration of First-line Treatment with Molecular Targeted-Therapy Is a Prognostic Factor in Metastatic Renal Cell Carcinoma

Aim: We investigated the prognostic factors associated with overall survival (OS) in patients with metastatic renal cell carcinoma (mRCC) who received molecular targeted-therapies.

Material and methods: A total of 66 patients underwent molecular targeted-therapies at the Kurume University between May 2008 and April 2014. Medical records were retrieved and analyzed retrospectively.

Results: The median OS was 25.9 [95% confidence interval (CI)=18.3-33.7] months. The median OS stratified by the Memorial Sloan Kettering Cancer Center risk classification was 49.3, 28.6 and 18.3 months for the favorable-, intermediate- and poor-risk groups, respectively. Univariate analyses for various factors revealed gender, pre-treatment C-reactive protein (CRP) level, best response to first-line treatment, the number of molecular targeted agents and the duration of first-line treatment with a median of 6 months, as prognostic variables. Multivariate analyses showed than two or more than three molecular targeted agents [two: hazard ratio (HR)=0.351, 95% CI=0.121-0.901; more than three: HR=0.193, 95% CI=0.069-0.495] and a duration of first-line treatment of more than 6 months (HR=0.203, 95% CI=0.078-0.498) to be independent prognostic factors.

Conclusion: Our results suggest that the duration of first-line treatment with molecular targeted-therapies is the strongest prognostic factor in patients with mRCC.