Disease Distribution at Presentation Impacts Benefit of IP Chemotherapy Among Patients with Advanced-Stage Ovarian Cancer

Background Ovarian cancer with miliary disease spread is an aggressive phenotype lacking targeted management strategies. We sought to determine whether adjuvant intravenous/intraperitoneal (IV/IP) chemotherapy is beneficial in this disease setting. Methods Patient/tumor characteristics and survival data of patients with stage IIIC epithelial ovarian cancer who underwent optimal primary debulking surgery from 01/2010 to 11/2014 were abstracted from records. Chi-square and Mann–Whitney U tests were used to compare categorical and continuous variables. The Kaplan–Meier method was used to estimate survival curves, and outcomes were compared using log-rank tests. Factors significant on univariate analysis were combined into multivariate logistic regression survival models. Results Among 90 patients with miliary disease spread, 41 (46%) received IV/IP chemotherapy and 49 (54%) received IV chemotherapy. IV/IP chemotherapy, compared with IV chemotherapy, resulted in improved progression-free survival (PFS; 23.0 versus 12.0 months; p = 0.0002) and overall survival (OS; 52 versus 36 months; p = 0.002) in patients with miliary disease. Among 78 patients with nonmiliary disease spread, 23 (29%) underwent IV/IP chemotherapy and 55 (71%) underwent IV chemotherapy. There was no PFS or OS benefit associated with IV/IP chemotherapy over IV chemotherapy in these patients. On multivariate analysis, IV/IP chemotherapy was associated with improved PFS (HR, 0.28; 95% CI 0.15–0.53) and OS (HR, 0.33; 95% CI 0.18–0.61) in patients with miliary disease compared with those with nonmiliary disease (PFS [HR, 1.53; 95% CI 0.74–3.19]; OS [HR, 1.47; 95% CI 0.70–3.09]). Conclusions Adjuvant IV/IP chemotherapy was associated with oncologic benefit in miliary disease spread. This survival benefit was not observed in nonmiliary disease.