Aromatase inhibitor therapy for estrogen receptor positive ovarian cancer

Abstract

15038 Background: Aromatase inhibitors (AI) are effective therapy for estrogen receptor positive breast cancer. We retrospectively reviewed our experience with AI therapy of 14 advanced ovarian cancer patients. Methods: Between March 2001 and January 2006, 14 women with ages ranging from 40 to 80 years received letrozole 2.5 mg orally once a day for periods of 2 to 36 months. All 14 patients had received prior chemotherapy and had recurrent disease. Eleven had received a mean of 2.8 (range 1–7) different chemotherapy regimens for advanced recurrent disease. Six of the 14 patients had received tamoxifen for periods of 1 to 12 months. Thirteen patients had advanced recurrent invasive epithelial ovarian cancer. One patient had advanced progressive ovarian tumor of borderline malignant potential with pleural involvement refractory to chemotherapy. Estrogen receptor status was positive in 13 patients and unknown in 1. CA-125 levels and clinical evaluations were available for all patients. Results: The mean baseline CA-125 level (U/mL) prior to letrozole therapy was 262, and ranged from 4.1 to 2723. The mean lowest CA-125 level after letrozole was started was 143, and ranged from 1.3 to 1158. Five of the 14 patients had CA-125 declines of ≥50% while on letrozole. Seven of the 14 patients remain on therapy at 2+ to 20+ months. Ten of the 14 patients had sustained clinical improvements or stability and no evidence of disease progression while on AI therapy for a mean period of 12 months with a range of 2 to 36 months. AI therapy was well tolerated. Conclusion: This limited and anecdotal experience suggests that AI therapy may be effective in advanced estrogen receptor positive ovarian cancer, including patients refractory to chemotherapy. AI therapy should be studied further in advanced ovarian cancer and in the adjuvant setting. No significant financial relationships to disclose.