Cytokine use and survival in the first-line treatment of ovarian cancer: a Gynecologic Oncology Group Study

Abstract

Background: Granulocyte colony stimulating factor (G-CSF) and erythropoietin stimulating agents (ESA) may be used to support patients during chemotherapy. We assessed whether G-CSF or ESA were associated with progression or death in patients with ovarian cancer. Methods: Patients with ovarian cancer following surgery, were on a protocol to evaluate bevacizumab with chemotherapy. Guidelines for administering G-CSF and ESA were specified in the protocol. Overall survival (OS) was analyzed with landmark procedures and multivariate, time-dependent hazard models. Results: Eighteen-hundred-seventy-three women were enrolled, with no differences in clinical and pathologic variables among treatment group. Performance status, hemoglobin, and white cell counts were associated with G-CSF and/or ESA usage during treatment. Nine patients received no protocol directed therapy, leaving 1864 patients for this review. One-thousand-one-hundred-twenty-five patients received neither ESA nor G-CSF; 311 received G-CSF but no ESA; 241 received ESA but no G-CSF; and 187 received both. Median survival following a five month landmark from the start of treatment was 34 versus 38 months for those who did versus did not receive ESA (multivariate hazard ratio: 0.989; 95% confidence interval: 0.849-1.15) and 40 versus 37 months for those who did versus did not receive G-CSF (multivariate hazard ratio: 0.932; 95% confidence interval: 0.800-1.08). Conclusions: Neither ESA nor G-CSF had a negative impact on survival after adjustment of prognostic factors among patients with ovarian cancer receiving chemotherapy. ESA may appear to be associated with shorter survival in univariate analyses because factors prognostic for ESA use are also prognostic for progression-free survival.