We have reviewed the experience of St. Mark's Hospital with double synchronous cancers of the large intestine. This occurs in 3.5 per cent of cancer resections, and in 75 per cent there are associated benign neoplasms. Patients with double or treble cancers fare much the same as those with single cancers, and the prognosis appears to be surprisingly favorable, even when the second growth is comparatively advanced. The second lesion, however, is usually not palpable at operation, and full clinical and radiologic investigation is therefore essential before any resection is undertaken for cancer of the colon or rectum.

Aged↗

PubMedDate not supplied

Localization of the gene for familial adenomatous polyposis on chromosome 5.

Colorectal cancer is the second most common cancer in the United Kingdom and other developed countries in the West. Although it is usually not familial, there is a rare dominantly inherited susceptibility to colon cancer, familial adenomatous polyposis (FAP; also often previously called familial polyposis coli). During adolescence affected individuals develop from a few hundred to over a thousand adenomatous polyps in their large bowel. These are sufficiently likely to give rise to adenocarcinomas to make prophylactic removal of the colon usual in diagnosed FAP individuals. Adenomas may occur elsewhere in the gastrointestinal tract and the condition is often associated with other extracolonic lesions, such as epidermoid cysts, jaw osteomata and fibrous desmoid tumours. Adenomata have been suggested to be precancerous states for most colorectal tumours. Knudson has suggested that the mutation for a dominantly inherited cancer susceptibility may be the first step in a recessive change in the tumour cells, and that the same gene may be involved in both familial and non-familial cases of a given tumour. Following up a case report of an interstitial deletion of chromosome 5 in a mentally retarded individual with multiple developmental abnormalities and FAP, we have now shown that the FAP gene is on chromosome 5, most probably near bands 5q21-q22.

Adenocarcinoma↗

PubMedDate not supplied

Patterns of mucus secretion in the colonic epithelium in familial polyposis.

Patterns of mucus secretion were investigated, by histochemical methods, in 24 colectomy specimens resected for familial polyposis coli. In this pre-malignant condition, mucus secretion contained an increased proportion of sialomucins as compared with normal colonic mucosa where sulphomucins predominate. These mucin changes (a) were more extensive in the left colon than in the right; (b) although consistently present in the mucosa adjacent to carcinomas, independent of their site, and around large polyps, they were also seen in patches of mucosa distant from the neoplastic growth; (c) they were more marked in the non-involved mucosa from patients who had developed carcinoma than in the non-cancer group. It was not possible to relate the type of mucin secreted and the degree of dysplasia. Similar alterations in mucus secretion have been previously described in colonic mucosa harbouring carcinoma both in humans and experimentally in rats, suggesting a relationship between altered glycoprotein synthesis and malignancy. The present results add further evidence to this hypothesis.

Adenoma↗