Fecal steroid excretion and degradation and breast cancer stage

Evaluation of excretion and degradation of fecal steroids in 74 women with breast cancer in relation to stage, tumor size, and histopathologic nodal status revealed significant differences in relation to stage of disease and tumor size. The level of total fecal steroids (mean ± SD in mg/g dry wt) in patients with Stage I disease was 40 + 20, Stage II = 56 ± 32, and Stage III = 75 ± 57 (P = 0.006). Secondary fecal steroids in women with Stage I disease were 26 ± 16, Stage II = 40 ± 27, and Stage III = 57 ± 34 (P = 0.003). Fecal steroid excretion and degradation was significantly higher in women with larger tumors, whereas nodal status did not contribute to observed differences indicating that dissemination of disease did not influence the results. These differences were noted to be independent of obesity since similar patterns of fecal steroid excretion were noted within the subgroups of both lean and obese women. Increased levels of total fecal steroids and secondary compounds apparently contribute to tumor promotion and may reflect a potential for excess estrogen synthesis since intestinal bacteria have the ability to synthesize estradiol, estrone, and 3,17-methoxyestradiol from secondary steroids present in the colon.