Despite Benefits, IP/IV Chemo Combo Underused in Ovarian Cancer

August 3, 2015

Despite trials showing a benefit when combining IP and IV chemo for ovarian cancer, fewer than 50% of eligible patients are currently receiving this treatment.

Despite clinical trials showing a benefit for combined use of intraperitoneal (IP) and intravenous (IV) chemotherapy for the treatment of ovarian cancer, fewer than 50% of eligible patients are currently receiving this treatment in clinical practice, according to the results of a study published in the Journal of Clinical Oncology.

In 2006, the results of the Gynecologic Oncology Group (GOG)-172 trial demonstrated a 16-month improvement in the median overall survival of women with ovarian cancer treated with combined IP/IV therapy compared with IV therapy alone.

In the current trial, Alexi A. Wright, MD, of Dana-Farber Cancer Institute, and colleagues wanted to examine if the use of this combined regimen was feasible and effective in clinical practice.

The researchers conducted a prospective study looking at 823 women diagnosed with stage III optimally cytoreduced ovarian cancer between 2003 and 2012 at six National Comprehensive Cancer Network (NCCN) institutions. IP/IV chemotherapy use was examined in the first cohort, and survival and treatment-related toxicities were examined in a propensity score–matched sample of 402 patients diagnosed between 2006 and 2012.

From 2003 to 2006, the use of IP/IV chemotherapy increased from 0% to 33%, with a further increase to 50% from 2007 to 2008. Despite these increases, the use of IP/IV therapy varied greatly from institution to institution between 2006 and 2012 from a rate of 4% to 67% (P < .001). Overall, 43% of patients who received IP/IV therapy received a modified regimen.

The researchers’ analysis found that younger women and those with fewer comorbidities were more likely to received IP/IV chemotherapy compared with IV chemotherapy (P < .002 for both).

In the group of 402 women, the researchers found that IP/IV chemotherapy was associated with a 3-year overall survival of 81% compared with 71% among women treated with IV chemotherapy alone for a hazard ratio [HR] of 0.68 (95% confidence interval [CI], 0.47–0.99).

“In a sensitivity analysis, the adjusted HRs ranged from 0.61 to 0.76 on excluding each institution one by one, indicating that the survival benefit observed was not driven by outcomes at a single institution,” the researchers wrote.

Women assigned IP/IV chemotherapy had higher rates of anemia and hospitalization compared with IV chemotherapy alone. In addition, women assigned IP/IV therapy had a higher odds of presenting with distant disease at first recurrence (58.8% vs 29.4%) than those women treated with IV chemotherapy alone.

“Despite frequent modifications to the GOG-172 regimen, we found that use of IP/IV chemotherapy in clinical practice is feasible and associated with improved survival compared with IV chemotherapy, consistent with results from randomized trials,” Wright and colleagues wrote, suggesting that “IP/IV is an important and possibly underused, evidence-based treatment strategy for improving outcomes in ovarian cancer.”