Premenopausal women with ER-positive breast cancer treated by surgery and receiving postoperative tamoxifen with or without LHRH analogues, who may have received pre or postoperative chemotherapy, or immunotherapy (for HER2-positive disease), are recruited to a double-blind randomized clinical trial, to receive either a dry extract of red clover (Promensil) as one tablet/day orally containing 80 mg isoflavones (treatment group), or one oral tablet/day without active principle (placebo group) for 24 months. All patients receive a diet-lifestyle intervention involving meetings with a dietician (physician) scheduled once a month for the first 6 months, and every 3 months thereafter. The dietician encourages patients to adhere to a macronutrient-balanced, low glycaemic load Mediterranean-type diet with personalized recommendations to increase intakes of unrefined cereals, pulses, vegetables, unrefined vegetable fats (e.g. olive oil, nuts, oil-containing seeds), and fish, and reduce intake of high-glycaemic-index foods and saturated animal fats. Patients are also encouraged to undertake regular physical activity. Outcomes are Menopausal Rating Score (MRS), body mass index (BMI), waist and hip girth, insulin resistance, and levels of cholesterol, triglycerides, and sex hormones.
The safety of the red clover preparation is assessed by pelvic ultrasound and mammograms for endometrial thickness and breast density, and by evaluation of the effects of the serum from treated and placebo patients on ER-positive BC cell lines.
