[Histochemical changes of the intestinal mucus in benign and malignant lesions of the colon and rectum].

The purpose of this work was to assess the presence of an abnormal production of sialomucins in different pathological conditions using high iron diamine-Alcian-blue staining. Sixty patients with a colorectal tumor and 95 subjects with either a normal colonic mucosa or suffering from non-malignant colorectal disease were studied. An increased production of sialomucins was searched in the first group on the mucosa of the tumor, on the transitional mucosa and on the surgical resection margins respectively and in the second group, on the colonic mucosa. A retrospective study was also performed on 48 patients who underwent curative resection for colorectal tumor. Twenty-four of those patients subsequently developed local tumor recurrence whereas the 24 other patients remained free of recurrence. The prospective study showed the presence of a constantly increased production of sialomucins in the neoplastic mucosa. These abnormalities were found in: 85 p. 100 of cases in the transitional mucosa, in 42 p. 100 and 25 p. 100 of the proximal and distal resection margins respectively, and in 73 p. 100 of patients with dysplasia. The retrospective study showed that 83 p. 100 of patients suffering from local recurrent tumors had an increased production of sialomucins whereas only 8 p. 100 of patients free of local recurrence presented such an abnormal production. This study confirms the presence of an increased production of sialomucins in various pathological colorectal conditions. It suggests that it is possible to individualize a high risk group of patients who might justify a closer follow-up with appropriate therapy.