Hormone Therapy May Improve Ovarian Cancer Survival

September 29, 2015

A recent study that gave hormone therapy to ovarian cancer patients with severe menopausal symptoms revealed that the treatment had a beneficial survival effect.

Hormone therapy was safely administered in women with severe menopausal symptoms after ovarian cancer treatment and may have a beneficial effect on survival, according to the results of a recent study published in the Journal of Clinical Oncology.

“This trial has shown that women who have severe menopausal symptoms after ovarian cancer treatment can safely take hormone replacement therapy without compromising their survival by doing so,” wrote Rosalind A. Eeles, FMedSci, MA, PhD, of the Institute of Cancer Research, United Kingdom, and colleagues. “Indeed, the survival advantage reported in a retrospective study has been confirmed in the randomized adjuvant hormone therapy trial, so administration of hormone replacement therapy for quality of life and survival benefit should be considered in patients with ovarian cancer.”

Eeles and colleagues initiated the Adjuvant Hormone Therapy trial in 1990 to assess the use of hormone therapy in women diagnosed with epithelial ovarian cancer. They recruited patients from 19 centers in three countries between 1990 and 1995. All patients had been diagnosed with epithelial ovarian cancer within the last 9 months.

The trial randomly assigned 150 women to adjuvant hormone therapy for 5 years or no hormone therapy. Patients assigned to the hormone therapy group had a median treatment time of 1.14 years. The primary endpoint was overall survival, which the researchers defined as time from randomization to death, and relapse-free survival.

The median follow-up of living patients is currently 19.1 years. Upon data analysis, 81% of patients had died: 71% of patients assigned hormone therapy and 91% of those who were not. The majority of deaths in both groups were due to ovarian cancer.

Overall survival was significantly improved in patients assigned hormone therapy (hazard ratio [HR], 0.63 [95% confidence interval (CI), 0.44–0.90]; P = .011). The restricted mean overall survival at 20 years was 8.5 for the hormone therapy groups compared with 5.7 for the controls group.

“It is interesting that the effect of adjuvant hormone therapy on overall survival, seen as early as 4 to 5 years after random assignment, seems to persist for 20 years,” Eeles and colleagues wrote. “A similar effect of post-treatment duration has been observed in breast cancer prevention trials with hormonal treatments, in which the preventive effect persisted 7 years after termination of the hormone treatment.”

Eighty-one percent of patients relapsed: 72% in the hormone therapy group and 91% in the control group. The mean recurrence-free survival at 20 years was 7.5 years for patients assigned hormone therapy compared with 4.7 years for the control group.

“Given the small size of the trial and the large CIs around HRs observed, a larger trial would be needed to give more accurate estimates of the true benefit of hormone replacement therapy,” the researchers wrote. “Given this uncertainty, clinical guidance on the basis of these results could include the administration of hormone replacement therapy for at least 1 year after surgical treatment for ovarian cancer.”