Secondary cytoreductive surgery prolongs PFS among women with recurrent ovarian cancer
Secondary cytoreductive surgery significantly increased PFS among a cohort of women with recurrent ovarian cancer, according to results of a randomized, phase 3 study presented during the ASCO20 Virtual Scientific Program.
An interim analysis of accumulated treatment-free survival showed secondary cytoreductive surgery also may contribute to long-term survival.
“Secondary cytoreductive surgery is a practical but controversial option for platinum-sensitive recurrence. This surgery has been standard of care for recurrent ovarian cancer in China and most patients have preferred the surgery for the past 20 years,” Rongyu Zang, MD, PhD, oncologist at Zhongshan Hospital of Fudan University in China, said during a presentation.
Between 2012 and 2019, Zang and colleagues randomly assigned 357 women with first relapsed ovarian cancer after a platinum-free interval of 6 months or more to secondary cytoreductive surgery followed by chemotherapy (n = 182; median age, 55.2 years) or second-line chemotherapy alone (n = 175; median age, 53.1 years). Nearly all women received a platinum-based second-line therapy.
PFS and OS served as primary endpoints.
Accumulated treatment-free survival, defined as OS time minus time of surgery and chemotherapy after randomization, served as the secondary endpoint.
More than three-quarters (76.7%) of women achieved complete resection. Researchers reported a grade 3 or higher postoperative 30-day complication rate of 5.2% and 60-day mortality of 0% for both groups.
Median follow-up was 36 months.
Results showed median PFS of 17.4 months in the surgery group vs. 11.9 months in the chemotherapy-alone group (HR = 0.58; 95% CI, 0.45-0.74). The surgery group also had a longer median time to start of first subsequent therapy (18.1 months vs. 13.6 months; HR = 0.59; 95% CI, 0.46-0.76).
Median accumulated treatment-free survival was unreached among the subgroup of women who achieved complete resection and 39.5 months among women who did not undergo surgery (HR = 0.59; 95% CI, 0.38-0.91). Accumulated treatment-free survival results showed the surgery group had superior long-term survival compared with the no-surgery group, with restricted mean survival time from 60 months to 72 months of 6.2 months vs. 4.2 months.
“Although the interim analysis of accumulated treatment-free survival indicates secondary cytoreductive surgery might potentially contribute to long-term survival compared with chemotherapy alone, the evidence of OS and accumulated treatment-free survival benefit from surgery needs further follow-up,” Zang said. “More is different — the complexity of surgery in surgical trials results in different findings."