Controversies regarding tamoxifen and uterine carcinoma.

An increasing number of cases of endometrial cancer in women receiving tamoxifen have been reported but most are from non-randomized studies and case reports. In the last year, there have been no further results either confirming or disproving an association between tamoxifen and endometrial cancer from randomized controlled studies in breast cancer patients and those participating in chemopreventative trials with tamoxifen. Several papers have examined the possible mechanisms behind tamoxifen's endometrial effects.