Purpose: To examine the effects of disease burden, complex surgery, and residual disease (RD) status on progression-free (PFS) and overall survival (OS) in patients with advanced epithelial ovarian cancer (EOC) or primary peritoneal cancer (PPC) and complete surgical resection (R0) or < 1 cm of RD (MR) after surgical cytoreduction.
Patients and methods: Demographic, pathologic, surgical, and outcome data were collected from 2,655 patients with EOC or PPC enrolled onto the Gynecologic Oncology Group 182 study. The effects of disease distribution (disease score [DS]) and complexity of surgery (complexity score [CS]) on PFS and OS were assessed using the Kaplan-Meier method and multivariable regression analysis.
Results: Consistent with existing literature, patients with MR had worse prognosis than R0 patients (PFS, 15 v 29 months; P < .01; OS, 41 v 77 months; P < .01). Patients with the highest preoperative disease burden (DS high) had shorter PFS (15 v 23 or 34 months; P < .01) and OS (40 v 71 or 86 months; P < .01) compared with those with DS moderate or low, respectively. This relationship was maintained in the subset of R0 patients with PFS (18.3 v 33.2 months; DS moderate or low: P < .001) and OS (50.1 v 82.8 months; DS moderate or low: P < .001). After controlling for DS, RD, an interaction term for DS/CS, performance status, age, and cell type, CS was not an independent predictor of either PFS or OS.
Conclusion: In this large multi-institutional sample, initial disease burden remained a significant prognostic indicator despite R0. Complex surgery does not seem to affect survival when accounting for other confounding influences, particularly RD.
© 2015 by American Society of Clinical Oncology.