Lehrer S, Brown RR, Lee C, Kalnicki S, Lipsztein R, Bloomer WD. Neuroendocrine abnormalities and the pathogenesis of estrogen-receptor-positive breast cancer. Mt Sinai J Med 1988; 55:272-5.  pdf


Breast cancer in women appears to have different manifestations, depending on the presence or absence of the estrogen receptor (ER). Although both ER-negative and ER-positive breast cancers are likely to be associated with the presence of an oncogene, ER-positive breast cancer is also associated with two clinical neuroendocrine abnormalities involving the pineal gland and olfaction, both of which may result from a defect in tryptophan metabolism along the kynurenine pathway.