CHICAGO—Among women previously treated with neoadjuvant chemotherapy followed by debulking surgery for advanced epithelial ovarian cancer, adding intraperitoneal to intravenous (IV) administration of postsurgical chemotherapy appears to be associated with a lower rate of disease progression, according to results of a randomized phase II trial presented at the 2016 American Society of Clinical Oncology (ASCO) Annual Meeting, held June 3–7 in Chicago (abstract 5503).
At 9 months, only 23.3% of study participants who received both intraperitoneal and IV chemotherapy experienced disease progression, compared with 42.2% of women receiving only IV chemotherapy—an 18.9% reduction in progressive disease rate, reported Helen J. Mackay, MD, divisional head of medical oncology and hematology at the Sunnybrook Odette Cancer Centre in Toronto, Canada.
Two hundred women who had undergone neoadjuvant platinum-based chemotherapy and debulking surgery, were randomly assigned to undergo subsequent IV chemotherapy or IV plus intraperitoneal chemotherapy. Most (82%) of the women participating in the trial had stage IIIC ovarian cancer, meaning that tumors had spread to their intraperitoneal cavities.
At 9 months, despite the 18.9% reduction in progressive disease associated with intraperitoneal chemotherapy, median progression-free survival (PFS) was similar for both study arms (11.3 for IV-only vs 12.5 months for IV plus intraperitoneal chemotherapy).
The study was not statistically powered to assess overall survival differences between study arms. Intraperitoneal chemotherapy was associated with a longer overall survival time than IV-only chemotherapy (59.3 vs 38.1 months), but this difference did not achieve statistical significance.
Adding intraperitoneal chemotherapy was not associated with significantly different toxicities. The rate of severe adverse events was 16% for women receiving intraperitoneal chemotherapy, compared with 23% among women receiving only IV chemotherapy, but this difference did not achieve statistical significance.
Global quality of life and physical functioning did not differ between the study arms; all women in the study experienced significant improvements over time as they recovered from surgery, regardless of chemotherapy regimen.
“Intraperitoneal chemotherapy is an effective yet underused treatment for women with newly diagnosed ovarian cancer that has been successfully removed surgically,” commented moderator Don Dizon, MD, an ASCO Expert in ovarian cancer. “These data now suggest that intraperitoneal treatment may have a role in the postoperative setting for women who initially were treated with intravenous chemotherapy.”
However, more research is needed to further define which patients will benefit most from this approach, Dr. Dizon cautioned.
The study authors plan to use tissue samples from this study to determine whether or not molecular subtypes are associated with intraperitoneal vs IV chemotherapy outcomes.