Neoadjuvant chemotherapy and chemotherapy cycle number: A national multicentre study.

OBJECTIVES: Six cycles of consolidation chemotherapy have become the standard for ovarian cancer treatment regimen following primary cytoreduction, yet with neoadjuvant chemotherapy (NAC), only 3 consolidation cycles are used. This study examines the effects of number of chemotherapy cycles in women with ovarian cancer that are being treated with neoadjuvant chemotherapy. In addition, we examined the effect of number of cycles on survival on consolidation and total chemotherapy.

METHODS: All patients with stage IIIC and IV high grade serous carcinoma (HGSC) were identified at 4 major Canadian cancer centers treated with NAC. A retrospective chart review was conducted using the medical charts and registry databases.

RESULTS: 403 NAC patients were identified. 47% had zero residual disease. Chemotherapy cycles were divided into <3cycles or ≥4cycles for NAC and consolidation treatments and analyzed with multivariate analysis. 139/403 (34.5%) received ≥4cycles of NAC and had a worse prognosis than <3cycles (p=0.011). 70/403 (17.4%) received ≥4cycles of consolidation treatment and there was no difference in survival (p=0.33) CONCLUSION: Women with advanced HGSC are managed with a combination of surgery and chemotherapy. This is a study of a homogenous cohort of patients with stage IIIC or IV high grade serous cancers who received NAC. ≥4cycles of NAC had a worse outcome than <3cycles likely due to poor prognostic factors or poor response. The number of consolidation cycles did not appear to make a difference in overall survival.