Expression of hormonal receptors (alpha-estrogen, beta-estrogen, progesteron), Ki-67 and P53 in endometrium of tamoxifen treated breast cancer patients

Tamoxifen is the most commonly prescribed adjuvant therapy for women with breast carcinoma ER+. It has agonist activity on the endometrium and is associated with an increased risk of endometrial carcinoma. The aim of this study was to evaluate the immunohistochemical changes on the histological endometrial modification from the patients treated with tamoxifen.

Methods: A group of 20 women selected from 125 patients with breast carcinoma, with adjuvant therapy. The criteria of selection were the histopathological proliferative changes of endometrium from these symptomatic patients. The 20 specimens of endometrium were evaluate immunohistochemycal by estrogen receptor alpha, beta, progesterone receptor, Ki-67 and P53.

Conclusions: The 20 endometrium specimen showed histological proliferative endometrial lessions, including polyps, hyperplasia and carcinoma. Immunohistochemical, benign lessions showned expression of estrogen alpha and beta receptor, low expression Ki-67 and absent expression of P53. These tests were negative in clear cell carcinoma, but were intens positive for Ki-67 and P53. In general, tamoxifen associated endometrial adenocarcinoma were characterized by a lower expression of estrogen receptor alpha, higher expression of progesterone receptor, and more frequent expression of estrogen receptor beta than endometrial spontaneous tumors.