CELLULAR PROLIFERATION, ESTROGEN-RECEPTOR, PROGESTERONE-RECEPTOR, ANDBCL-2 EXPRESSION IN GNRH AGONIST-TREATED UTERINE LEIOMYOMAS

Gonadotropin-releasing hormone (GnRH) agonists are commonly used in th e treatment of uterine leiomyomas, but little is known about their his tological and cellular effects on these neoplasms. We examined a cellu lar proliferation index as determined by the nuclear antigen Ki-67 and proliferating cell nuclear antigen (PCNA) expression, estrogen recept or (ER), and progesterone receptor (PR) expression in 27 leiomyomas fr om patients treated with the GnRH agonist leuprolide acetate CLA) and compared them with 33 untreated controls. All leiomyomas were removed by myomectomies from premenopausal woman after 2 to 6 months of LA tre atment or in the follicular phase of the menstrual cycle in the untrea ted controls. Histological features examined included cellularity, nuc lear atypia, vascular changes (dilated, thickened, or thrombosed vesse ls), edema, calcification, hemorrhage, necrosis, hyalinization, and mi totic activity. Although no difference was found between GnRH-treated and nontreated groups with respect to most histological features exami ned, immunohistochemical studies showed a significant decrease in the cellular proliferation index, ER, and PR expression in the LA-treated cases compared with nontreated controls. The cellular proliferation in dex, ER, and PR expression decreased by 85%, 49%, and 36%, respectivel y, in the LA-treated group as compared with controls (P <.001). A subs et of cases from the LA-treated and nontreated groups were also analyz ed with respect to bcl-2 tan inhibitor of apoptosis) expression, and n o significant difference between the LA-treated and nontreated groups was observed with both groups showing a strong (>75% of cells) cytopla smic staining pattern. Results of this: study show that LA treatment o f leiomyomas results in a decrease in number of cyclin cells. Copyrigh t (C) 1998 by W.B. Saunders Company.