UTERINE LEIOMYOMATA AND ENDOMETRIAL PROLIFERATION IN POSTMENOPAUSAL WOMEN TREATED WITH THE ANTIESTROGEN TAMOXIFEN

Two cases of fibroid growth and endometrial proliferation in postmenop ausal women on tamoxifen (anti-oestrogen) therapy for breast cancer ar e described. Oestrogen in association with growth factors may control fibroid growth and differentiation. The possible mechanisms and conseq uences of tamoxifen-induced fibroid growth are discussed. Oestrogen re sponsive tissues demonstrate a differential and contrasting response t o tamoxifen and caution should be exercised in the expansion of its cl inical application. Women on long-term tamoxifen therapy may benefit f rom ultrasound surveillance of their uterus and endometrium, with biop sy in suspicious cases, as there is a paucity of data on malignant tra nsformation of these benign lesions induced by tamoxifen therapy.