The associations of obesity, lymph node status and prognosis in breast cancer patients: dependence on estrogen and progesterone receptor status.

Breast cancer patients who are obese have a higher risk of lymph node metastases and a poorer prognosis than those who are slim. It has been claimed that estrogens derived from fat are important for these associations. If estrogens are important, these relationships must be stronger in the hormone receptor-positive than in the hormone receptor-negative groups.