High-risk early breast cancer in patients under 40 years of age: Improved clinical outcome with total estrogen blockade and tailored chemotherapy.

This multicenter prospective trial assessed the outcome in 63 patients, 40 years of age or younger, with high-risk early breast cancer (HREBC), included in an ovarian protection study. The patients were treated with a luteinizing hormone-releasing hormone (LH-RH) analogue administered for 5 years, tailored chemotherapy and an aromatase inhibitor, in estrogen receptor-positive (ER(+)) patients. T-regulatory cells (T-regs) and vascular endothelial growth factor (VEGF) were measured at baseline and yearly. The mean age of the patients was 36 years (range 26-40). Sixty-five percent had ER(+) tumors, 24% had negative axillary nodes with tumors >1 cm and high histological grade with lymphovascular invasion, while 76% had a mean of 3.6 positive axillary nodes (range 1-21). Serum estradiol was maintained at values <40 pg/ml in all of the patients. A statistically significant decrease in VEGF (P<0.0001) and T-regs (P<0.0001), with respect to baseline values, was observed after LH-RH administration. After a median follow-up of 110 months, the 10-year progression-free and overall survival rates were 86.1 and 89.7%, respectively. These data revealed that the administration of an LH-RH analogue to HREBC patients, followed by chemotherapy and hormonal therapy, decreased VEGF and T-regs and improved the expected clinical outcome.