The rapid development of new drugs, the overall survival of patients with metastatic renal cell carcinoma (mRCC) has increased over the last decade. However, resistance to these agents would acquire inevitably. Two of the important strategies to overcome the drug resistance is the optimization of the drug sequence and combination therapy with a variety of novel drugs. In this study, we aimed to describe and analyze the drug sequence and the survivals on a real-world basis.
Since 2005 to 2015, we retrospectively analyzed patients with mRCC who received at least 2 lines of anticancer therapies in Chang Gung Memorial hospital at Linkou in Taiwan. Basic characteristics were collected from medical records. Student t test, Kaplan-Meier survival analysis with log-rank test and Cox-regression model analysis were used.
A total of 74 patients were retrieved for analysis from the databank. The most common first-line treatment was sunitinib (n = 44, 59.5%) and median progression-free survival 1(PFS1) of sunitinib was 7.9 (95% confidence interval [CI]: 5.8-10.8) months. The most common second-line treatment was everolimus, and its median PFS2 was 6.4 (95% CI: 1.2-11.6) months. Most intriguingly, no matter which line of immunotherapy (interleukin-2) or cytokine therapy (interferon) was used; patients exposed to one line of cytokine/immunotherapy would have significant better survivals than those who never exposed to it. (Log rank test, P = 0.003) In addition, patients having a PFS1 less than 6.7 months would have worse overall survivals (OS). (Log rank test, P = 0.0028) Patients who fit the sequence of sunitinib followed by everolimus have a PFS1 + PFS2 of 16.9 and a OS of 30.4 months, respectively.
Our data suggested adding cytokine/immunotherapy into current sequential targeted therapies as any line of treatment might improve overall survivals.
Clinical trial identification
All authors have declared no conflicts of interest.