Exemestane Shows Promise in Preventing Endometrial Cancer

Strategic Insights -

A new study published in Clinical Cancer Research, a journal of the American Association for Cancer Research, suggests that exemestane, an aromatase inhibitor, may be effective in preventing endometrial cancer. The multi-center, single-arm pilot study enrolled 40 postmenopausal women with endometrial intraepithelial neoplasia (EIN) or low-grade endometrial cancer, who underwent hysterectomy and received exemestane (25 mg daily for 21-42 days) as a preventive intervention. The primary objective was to determine the change in proliferation, measured by Ki-67 expression, in pre- and post-treatment endometrial tissues specimens.

Key Takeaways:

  • The pilot study aimed to evaluate exemestane as a preventive intervention for endometrial cancer in postmenopausal women with EIN or low-grade endometrial cancer.
  • 40 participants were accrued to the study, with preoperative diagnoses including EIN (n=11, 27.5%), grade 1 EC (n=26, 65%), and grade 2 EC (n=3, 7.5%).
  • The median Ki-67 score decreased from 40.7% [IQR (33.9, 50.3)] at baseline to 18.1% [IQR (8.8, 31.8)] at surgery, representing a median absolute change of 20.4% [IQR (-29.9, -6.7), p
  • The researchers concluded that exemestane warrants further evaluation for the prevention of endometrial cancer.
  • The study was conducted at the UW Carbone Cancer Center, and the research was peer-reviewed.

Statistics:

  • 40 postmenopausal women with EIN or low-grade endometrial cancer participated in the study.
  • 27.5% of the participants had EIN, 65% had grade 1 EC, and 7.5% had grade 2 EC.
  • The median Ki-67 score decreased by 20.4% after treatment.
  • 21-42 days was the duration of exemestane treatment.

Sources:

  • "Pilot Study of Daily Exemestane in Women with Endometrial Intraepithelial Neoplasia or Low Grade Endometrial Cancer." Clinical Cancer Research, 2025.
  • NewsRx. Research Conducted at UW Carbone Cancer Center Has Provided New Information about Endometrial Cancer (Pilot Study of Daily Exemestane in Women with Endometrial Intraepithelial Neoplasia or Low Grade Endometrial Cancer). OBGYN & Reproduction Week. October 20, 2025; p 800.