Clinical experiences at St. Mark's Hospital with multiple synchronous cancers of the colon and rectum.

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.