Tailoring adjuvant treatments for the individual patient with luminal breast cancer.

Estrogen Receptor-positive/HER-2 negative breast cancers represent a heterogeneous group of tumors. Luminal A and B tumor subtypes can be identified through immunohistochemical assessment of estrogen and progesterone receptor, Ki-67 and HER-2 status. Patients with high levels of expression of steroid hormone receptors and low proliferation (Luminal A) are commonly cured with endocrine therapy alone. Patients with doubtful endocrine responsiveness or with high proliferation index (Luminal B/Her-negative) require the addition of chemotherapy to the best endocrine therapy. Controversies still exist on the identification of those patients who do not benefit from chemotherapy. Tailored adjuvant treatments should be considered in the therapeutic algorithm of patients with luminal tumors.