Endometrial Lesions After Tamoxifen Therapy in Breast Cancer Women

Abstract

Tamoxifen, a nonsteroidal antiestrogen with a partial estrogen-antagonist activity, is widely used as a hormonal adjuvant therapy for breast cancer in women with positive receptors for estrogens. Its prolonged administration has been associated with a series of collateral effects, among which the endometrial carcinoma is the most important. The aim of our study was to investigate an eventual correlation between a therapy with tamoxifen and the onset of endometrial lesions. We recruited 228 postmenopausal patients who had been operated on for breast cancer. They were divided into two groups according to the presence of positive or negative estrogen receptors. The group with positive receptors was subjected to hormonal adjuvant therapy by tamoxifen (20 mg/day for 5 years), while the group with negative receptors was not treated. All the patients underwent a hysteroscopic evaluation of the uterine cavity before and after treatment. The follow-up carried out 5 years later showed the presence of a statistically higher risk (p < 0.00001) of endometrial lesions, such as low glandular hyperplasia and polyps, than in the treated patients compared with untreated patients. On the other hand, because there was no onset of endometrial carcinoma, the risk of this kind of lesion turned out to be practically absent. In all the treated patients who did not evidence any endometrial lesions (n = 90) and in all those with negative receptors (n = 104) the endometrium seemed to have an atrophic aspect. In conclusion, according to these data, we believe that hormonal adjuvant therapy by tamoxifen (20 mg/day), associated with a periodic hysteroscopic evaluation, and eventually a directed biopsy of the endometrium in order to keep under control the frequent onset of benign endometrial lesions, does not absolutely seem to increase the risk of endometrial carcinoma.

Clinical Problem Solving

“…It has been shown to prevent breast cancer in high‐risk women 40 . Although tamoxifen has antiestrogenic effects on breast tissue, it has a positive estrogenic effect on the postmenopausal endometrium and myometrium and results in an increased number of uterine and endometrial abnormalities 41 , 42 41 .…”

Prognosefaktoren des Endometriumkarzinoms - Ein Vergleich klinischer und immunhistochemisch bestimmter Parameter

“…Demgegenüber zeigten andere Studien kein signifikant erhöhtes Risiko oder fanden vornehmlich Niedrig-Risiko-Karzinome (Maugeri et al, 2001;Nishimura et al, 2001). …”

Differences in estrogen and progesterone receptor expression in endometrial polyps and atrophic endometrium of postmenopausal women with and without exposure to tamoxifen

“…A higher incidence of endometrial alterations, such as polyps, hyperplasia, carcinoma and sarcoma, have been reported in menopausal tamoxifen users, in addition to an increased risk of endometrial malignant neoplasms (9)(10)(11)(12)(13)(14).…”

“…Among the endometrial alterations reported in tamoxifen users, polyps are the most common, with a prevalence of 13-30% (10,12,15,16). In patients treated with tamoxifen, microscopic analysis revealed that polyps are more translucent, edematous and fibrotic, with less stromal cellularity (10).…”