A prospective study on women with a history of breast cancer and with or without estrogen replacement therapy

Objective: Because a categorical refusal of estrogen replacement therapy (ERT) from postmenopausal patients with a history of breast cancer is not based on any research evidence and may be more harmful than beneficial, we evaluated the safety and efficacy of ERT in these women. Methods: We recruited 131 patients who had been treated for breast cancer for a mean of 4.2 years (range 1 month to 20 years) before. Eighty-eight decided to use ERT, whereas 43 refused or had no need for ERT. At recruitment. the patients were carefully examined for breast and gynaecologic findings. Non-hysterectomized patients wishing to receive ERT (n = 54) then started using estradiol as oral tablets (2 mg/day) (n = 44) or as transdermal gel (1.5 mg/day) (n = 10) in combination with 10-day courses of oral medroxyprogesterone acetate at 4-week intervals, whereas hysterectomized patients (n = 34) used only estradiol, orally (2 mg/day) (n = 31) or transdermally (1.5 mg/day) (n = 3). The patients using ERT were carefully examined 6 and 12 months later, and then annually at a specific outpatient department, and the mean follow-up time is now 2.5 years (range from 1 month to 5.2 years, 216 woman-years). The 43 patients not wishing to receive ERT were followed annually at the oncologic department for a mean of 2.6 years (range from 1 month to 4.7 years), and served as a control group. Results: ERT significantly reduced climacteric symptoms, and the Kupperman score fell by 63%, from 26.9 +/- 8.6 to 9.9 +/- 6.7 (mean +/- SID). In non-hysterectomized women, medroxyprogesterone acetate triggered withdrawal bleeding in all except seven women. Seven patients (13%) experienced spotting during ERT. In 27 women, endometrial thickness exceeded 10 mm. and two of the total of 54 patients (3.7%) had simple hyperplasia. This vanished spontaneously in 3-6 months. Ten patients terminated the use of ERT within the first 12 to 39 months due to the lack of severe vasomotor symptoms (n = 4) or due to the recurrence of breast cancer or to cancer of the contralateral breast (n = 6). Eighty-one of the 88 patients (92%) using ERT showed no evidence of recurrence, whereas five patients (5.7%) had recurrence in 12-36 months and two patients (2.3%) developed a cancer of the contralateral breast in 14-24 months; another one of those wanted to continue with ERT. Thus the combined risk of recurrence or a new cancer of the contralateral breast in ERT users was 7/216 woman-years (3% per year). In the control group, 38 of 43 patients (88.4%) showed no evidence of recurrence or contralateral cancer, whereas four patients had recurrence and one developed a contralateral breast cancer (5.112 woman-years, 4% per year). Conclusions: Symptomatic climacteric patients with a history of breast cancer benefited from E RT without increasing their risk of recurrence, but the short follow-up and the small number of patients limit any definitive recommendations. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.