IP CHEMOTHERAPY FOR OVARIAN CANCER

In an analysis of Gynecologic Oncology Group (GOG) studies reported in the Journal of Clinical Oncology, Tewari et al found that intraperitoneal chemotherapy was associated with a survival advantage compared with intravenous chemotherapy in women with advanced ovarian cancer.

Study Details

The retrospective analysis involved data from 876 patients in the phase III GOG studies 114 and 172, both of which randomly assigned patients to intraperitoneal (combined n = 440) or intravenous (combined n = 436) chemotherapy. Regimens consisted of intravenous paclitaxel and intravenous cisplatin vs intravenous carboplatin, intravenous paclitaxel, and intraperitoneal cisplatin in GOG 114 and intravenous paclitaxel and intravenous cisplatin vs intraperitoneal cisplatin and intraperitoneal paclitaxel in GOG 172. Patients in the intraperitoneal and intravenous groups were generally balanced for baseline characteristics.  

Improved Overall Survival

Median follow-up was 10.7 years. Median overall survival with intraperitoneal therapy was 61.8 months (95% confidence interval [CI] = 55.5–69.5) vs 51.4 months (95% CI = 46.0–58.2 months) for intravenous therapy (hazard ratio [HR] adjusted for baseline demographic and clinicopathologic factors = 0.77, P = .002).

In a subgroup analysis, intraperitoneal treatment was associated with significantly improved survival among patients with gross residual (≥ 1 cm) disease vs no visible disease (adjusted HR = 0.75, P = .006). There was a significant association of reduced risk of death with each cycle of intraperitoneal completed (adjusted HR = 0.88, P < .001, for each cycle). Younger patients were more likely to complete intraperitoneal regimens, with probability of completion decreasing by 5% with each additional year of age (odds ratio = 0.95, P < .001).

Factors in Poorer Outcome

Factors significantly associated with poorer overall survival included clear/mucinous vs serous histology (adjusted HR = 2.79, P < .001), gross residual vs no visible disease (adjusted HR = 1.89, P < .001), and fewer vs more cycles of intraperitoneal chemotherapy (adjusted HR = 0.88, P < .001).

The investigators concluded: “The advantage of [intraperitoneal] over intravenous chemotherapy extends beyond 10 years. [Intraperitoneal] therapy enhanced survival of those with gross residual disease. Survival improved with increasing number of [intraperitoneal] cycles.”

John K. Chan, MD, of California Pacific/Palo Alto Medical Foundation/Sutter Research Institute, San Francisco, is the corresponding author of the Journal of Clinical Oncology article.

The study was supported by National Cancer Institute grants, a Gynecologic Oncology Group Young Investigator Award, and John A. Kerner Denise & Prentis Cobb Hale Research Award.

Thomas J. Herzog, MD, reported honoraria from Johnson & Johnson, Genentech, and AstraZeneca.