Platinum versus platinum-combination chemotherapy in platinum-sensitive recurrent ovarian cancer: a meta-analysis using individual patient data

The majority of women with ovarian cancer develop recurrent disease. For patients with a platinum-free interval of > 6 months, platinum-based chemotherapy is a treatment of choice. The benefit of platinum-based combination chemotherapy in randomized trials varies, and a meta-analysis was carried out to gain more secure information on the size of the benefit of this treatment. We initiated a systematic review and meta-analysis following a pre-specified protocol to determine whether combination chemotherapy is superior to single-agent platinum chemotherapy in women with relapsed platinum-sensitive ovarian cancer. A total of five potentially eligible randomized trials were identified that had used combination-platinum chemotherapy versus single-agent platinum chemotherapy in women with relapsed platinum-sensitive ovarian cancer. For one trial (190 patients), adequate contact with the investigators could not be established. Therefore, four trials that randomly assigned 1300 patients were included, with a median follow-up of 36.1 months. Overall survival (OS) analyses were based on 865 deaths and demonstrated evidence for the benefit of combination-platinum chemotherapy (HR = 0.80; 95% CI, 0.64-1.00; P = 0.05). Progression-free survival (PFS) analyses were based on 1167 events and demonstrated strong evidence for the benefit of combination-platinum chemotherapy (HR = 0.68; 95% CI, 0.57-0.81; P < 0.001). There was no evidence of a difference in the relative effect of combination-platinum chemotherapy on either OS or PFS in patient subgroups defined by previous paclitaxel (Taxol) treatment (OS, P = 0.49; PFS, P = 0.66), duration of treatment-free interval (OS, P = 0.86; PFS, P = 0.48) or the number of previous lines of chemotherapy (OS, P = 0.21; PFS, P = 0.27). In this individual patient data (IPD) meta-analysis, we have demonstrated that combination-platinum chemotherapy improves OS and PFS across all subgroups. This provides the strongest evidence to date of the benefit of combination-platinum over single-agent platinum.