Tryptophan metabolism in breast cancer. correlation with urinary steroid excretion

Urinary excretion of tryptophan metabolites, etiocholanolone, androsterone, and 17-hydroxycorticosteroids (17-OHc.s.), was measured in 25 patients with breast cancer and in 12 similarly aged control women. Twelve of the 25 patients had elevated excretions of metabolites of the kynurenine-niacin pathway, and, in these patients, the excretion of etiocholanolone was significantly lower than in controls or in patients with normal tryptophan metabolism.