Aromatase inhibitor boosts fertility chances after breast cancer

Letrozole appears to be superior to tamoxifen for ovarian stimulation in breast cancer patients who want to preserve their fertility through embryo cryopreservation, researchers reported at ASRM 2004, the annual meeting of the American Society for Reproductive Medicine that is currently underway in Philadelphia.

Dr. Kutluk H. Oktay of Weill Medical School of Cornell University in New York presented his team’s findings of 65 women with breast cancer who underwent IVF for embryo cryopreservation during the interval between surgery and chemotherapy.Dr. Oktay and colleagues divided the study group into three groups: those receiving tamoxifen, those receiving tamoxifen plus low-dose follicle stimulating hormone therapy (FSH) and those receiving letrozole and low-dose FSH. All patients underwent IVF for egg retrieval.Dr. Oktay told Reuters Health that women in the letrozole arm of the study were able to produce more eggs and have more embryos develop than women in either of the other two arms. “[Letrozole] produced significantly more mature eggs than tamoxifen,” Dr. Oktay said. Women in the tamoxifen-alone group yielded 13 total embryos, those on tamoxifen plus low-dose FSH yielded 38 and those on letrozole plus FSH yielded 53 embryos.”We now have our first pregnancy. That woman is now in her twelfth week. We’ve heard the [fetal] heartbeat and everything appears normal,” Dr. Oktay said. “We’ll continue to follow the women in this study for 4 years. So far, there has been no recurrence of cancer.”Letrozole is administered intramuscularly on the second or third day of menstruation. “There is typically about 6 weeks between surgery and the start of chemotherapy. That should be enough time to [harvest eggs],” Dr. Oktay noted. “This an emerging drug in breast cancer. It appears to be better than tamoxifen. Letrozole boosts egg production so that the future chance of egg retrieval and conception are boosted…We’ve got a long way to go, but this appears promising,” Dr. Oktay commented. (Source: American Society for Reproductive Medicine: Reuters Health News: Martha Kerr: Oncolink: October 2004.)