Bile acids in patients suffering from colorectal carcinoma--a pilot study

Bile acids are increasingly discussed in the genesis of colorectal carcinoma. In a pilot study we analysed bile acids in tumor tissue, tumor-free mucosa, serum, and feces of 6 patients with rectal and 3 patients with colonic carcinoma. 5 patients dead from nongastroenterological diseases and two operated on for benign colonic stenosis served as controls for colorectal mucosa, 16 healthy persons as controls for feces and serum. Bile acids and their sulphates were determined after differential solvolysis by gas-liquid chromatography on QF-1 columns. Serum lithocholic acid was significantly (p less than 0, 05) elevated in all carcinoma patients. The feces showed a trend towards increased secondary bile acids. Tumor-free mucosa of patients with rectal carcinoma showed elevated unsulphated bile acids, sulphated lithocholic acid (p less than 0, 05) and sulphated chenodeoxycholic acid (p less than 0, 025) were significantly decreased. In rectal carcinoma tissue total bile acids were elevated, cholic acid (p less than 0, 01) and sulphated lithocholic acid decreased (p less than 0, 05). In nonaffected colonic mucosa of patients with colonic carcinoma total bile acids were decreased, in colonic carcinoma tissue only traces of bile acids were found. Whether these changes are causes or rather consequences of colorectal tumors--e.g. tumor-induced stasis in the gut--and whether they may be useful for diagnosis remains to be elucidated in further studies.