A prospective study evaluating the clinical relevance of a chemoresponse assay for treatment of patients with persistent or recurrent ovarian cancer

Objective. Use of in vitro chemoresponse assays for informing effective treatment selection is a compelling clinical question and a topic of debate among oncologists. A prospective study was conducted evaluating the use of a chemoresponse assay in recurrent ovarian cancer patients. Methods. Women with persistent or recurrent ovarian cancer were enrolled under an IRE-approved protocol, and fresh tissue samples were collected for chemoresponse testing. Patients were treated with one of 15 protocol-designated treatments empirically selected by the oncologist, blinded to the assay results. Each treatment was classified by the assay as: sensitive (S), intermediate (I), or resistant (R). Patients were prospectively monitored for progression-free survival (PFS) and overall survival (OS). Associations of assay response for the physician-selected treatment with PFS and OS were analyzed. Results. A total of 262 evaluable patients were enrolled. Patients treated with an assay-sensitive regimen demonstrated significantly improved PFS and OS while there was no difference in clinical outcomes between I and R groups. Median PFS was 8.8 months for S vs. 5.9 months for I + R (hazard ratio [HR] = 0.67, p = 0.009). The association with assay response was consistent in both platinum-sensitive and platinum-resistant tumors (HR: 0.71 vs. 0.66) and was independent of other covariates in multivariate analysis (HR = 0.66, p = 0.020). A statistically significant14-month improvement in mean OS (37.5 months for S vs. 23.9 months for I + R, HR = 0.61, p = 0.010) was demonstrated. Conclusions. This prospective study demonstrated improved PFS and OS for patients with either platinum-sensitive or platinum-resistant recurrent ovarian cancer treated with assay-sensitive agents. (C) 2013 The Authors. Published by Elsevier Inc All rights reserved.