000344: TAMOXIFEN AND OVARIAN CYSTS: A PROSPECTIVE STUDY

Objective: To prospectively follow a group of women with breast cancer on tamoxifen (TAM) for the development of ovarian cysts. Methods: Between March 2002 and March 2003, 100 women with breast cancer on TAM were followed every 3 months with pelvic exam and ultrasonography for one year, occurrence and outcome of ovarian cyst were evaluated. Results: The duration of treatment was 22.66 months. The mean age was 50.55 years. In first ultrasonography, incidence of ovarian cyst was 6%, but in subsequent follow up visit, 58 of patients with normal sonography in the first visit didn’t continue the study and 4 new cases of ovarian cyst were detected in others. The mean duration of treatment of women who developed ovarian cysts was not significantly different (21.3 and 24.84 months, respectively). Out of 74 postmenopausal and out of 26 postmenopausal women developed ovarian cysts. The average diameter of cysts in premenopausal patient was 31±7 mm, and in postmenopausal patients was 33±13 mm. All cysts were simple except one postmenopausal patient with multiloculated paraovarian cyst. In 3 patients, the cysts resolved spontaneously or with on discontinuation of TAM, and one patient was lost to follow up. One patient died due to progressive breast disease. Three patients underwent laparatomy, histological exam confirmed simple, follicular and paraovarian cyst. Conclusion: Ovarian cyst is a rather frequent event in women with breast cancer on TAM. The majority of the cysts are simple, which may resolve spontaneously or with discontinuation of TAM.