BACKGROUND: Randomized trials in postmenopausal women have shown a benefit to substituting aromatase inhibitors for tamoxifen or using them sequentially following a full course of tamoxifen. The aromatase inhibitor letrozole has also been utilized for ovarian induction in premenopausal women. CASE REPORT: A premenopausal woman with early stage breast cancer became amenorrheic with adjuvant chemotherapy, and remained so during 5 years of daily tamoxifen. After discontinuing tamoxifen, laboratory studies confirmed an apparent postmenopausal state. Menses resumed following a 2-week course of letrozole. CONCLUSION: Aromatase inhibitors need to be used with caution in women who stop menstruating following adjuvant chemotherapy or tamoxifen.
BACKGROUND: Randomized trials in postmenopausal women have shown a benefit to substituting aromatase inhibitors for tamoxifen or using them sequentially following a full course of tamoxifen. The aromatase inhibitor letrozole has also been utilized for ovarian induction in premenopausal women. CASE REPORT: A premenopausal woman with early stage breast cancer became amenorrheic with adjuvant chemotherapy, and remained so during 5 years of daily tamoxifen. After discontinuing tamoxifen, laboratory studies confirmed an apparent postmenopausal state. Menses resumed following a 2-week course of letrozole. CONCLUSION: Aromatase inhibitors need to be used with caution in women who stop menstruating following adjuvant chemotherapy or tamoxifen.
Authors: Jacquie Chirgwin; Zhuoxin Sun; Ian Smith; Karen N Price; Beat Thürlimann; Bent Ejlertsen; Hervé Bonnefoi; Meredith M Regan; Aron Goldhirsch; Alan S Coates Journal: Breast Cancer Res Treat Date: 2011-09-04 Impact factor: 4.872