Endometrial changes with chronic tamoxifen use.

Tamoxifen is a nonsteroidal antiestrogenic drug used successfully to reduce recurrences in all stages of breast carcinoma. Recent reports have emphasized an increased incidence of premalignant and neoplastic endometrial changes that have questioned the risk-benefit ratio of this medication. It appears that the use of tamoxifen increases the incidence of endometrial abnormalities in 1.2 individuals per 1000 women treated with tamoxifen, increasing to 6.3 per 1000 women after 5 years. However, current evidence suggests that the use of tamoxifen as an adjuvant for breast carcinoma overrides the risk of developing endometrial neoplasias. It is not clear which long-term method of surveillance is most cost-effective for these patients. Therefore, individuals should be alerted to the potential risks of tamoxifen use. At present, the screening method of choice should be decided by each individual practitioner, bearing in mind that any vaginal bleeding should be readily investigated. If high-grade hyperplasias of the endometrium or cancer are found, management should be tailored in conjunction with the physician responsible for the woman's breast care.