[A modified guaiac test for the early detection of tumors of the intestinal tract (author's transl)].

Of 1400 patients who were submitted to the Haemoccult test, 46 showed a postive result. Among other things there were 29 polyps, of which 3 already showed a focal carcinoma, and 5 carcinomata of the large intestine and 3 gastric carcinomata were also diagnosed. Over 70% of the tumor hosts had observed bleeding per anum at some time. In order to detect the number of false nagative results, patients were investigated in the same way even when the Haemoccult test had been negative three times. In this way 55 polyps were found as well as 7 partly advanced carcinomata of the large intestine. 35% of the Haemoccult-negative patients stated bleeding per anum in their history. The number of false negative findings must be considerably higher than previously estimated.