Women with low-grade serous carcinoma (LGSC), a rare subtype of epithelial ovarian or peritoneum cancer, are more likely to survive when treated with hormonal therapy after surgery and chemotherapy, new research suggests.
In the study, hormonal maintenance therapy following surgery and platinum-based chemotherapy more than doubled the time to disease progression compared with routine observation. Overall survival also increased significantly among the subset of women who achieved a complete response following chemotherapy.
The study, “Hormonal Maintenance Therapy for Women With Low-Grade Serous Cancer of the Ovary or Peritoneum,” appeared in the Journal of Clinical Oncology.
LGSC, a disease typically diagnosed in women in their 40s or 50s, accounts for 10 percent of serous carcinomas of the ovary/peritoneum. According to prior research by the University of Texas MD Anderson Cancer Center, the disease is more resistant than high-grade serous carcinomas to chemotherapy.
“There is a true unmet need for these patients. Roughly 70 percent of women with this disease will experience a recurrence of the cancer at some point,” David M. Gershenson, MD, the study’s corresponding author, said in a news release. “Our group published research demonstrating that hormonal therapy showed promise in the recurrent setting, with most patients responding or having stable disease. It was a natural progression over time that we began to study this up front, after women received their primary chemotherapy.”
Along with his team, Gershenson — a professor of gynecologic oncology and reproductive medicine — conducted a retrospective cohort study. They examined data from 203 women with stage 2-3 LGSC treated at MD Anderson between 1981 and 2013. Among the study participants, 70 had received hormonal therapy following surgery and chemotherapy, and 133 received surveillance.
They found that women who received hormonal therapy as maintenance took more than double the time to see their disease progress, compared to those receiving routine observation. Their median progression-free survival was 64.9 months versus 26.4 months in the surveillance group.
Researchers observed no statistically significant difference in overall survival between the two groups (102.7 months vs. 115.7 months, respectively). But a subgroup analysis revealed that women who were disease-free after the chemotherapy treatment had significantly higher overall survival when receiving hormonal therapy (191.3 months vs. 106.8 months). Progression-free survival was also higher in this subgroup (81.1 months vs. 30.0 months).
“Hormonal therapy has shown promising results in reducing cancer recurrence, and there is increasing interest in integrating this approach into first-line therapy,” said Gershenson. “If confirmatory research in a clinical trial setting shows hormonal maintenance therapy can prevent or delay recurrence of this cancer subtype, it would be practice-changing.”
A prospective Phase 3 trial has now been designed to confirm the findings from this retrospective study. The trial will compare chemotherapy plus surveillance, chemotherapy plus hormonal therapy and hormonal therapy alone.