Metastases of the digestive tract. Report of 77 cases and review of the literature.

In addition to personal observations of 77 patients with one or more metastatic sites in the gastrointestinal tract, the authors reviewed over 1000 similar cases in the literature. The general radiologic aspects of each location (oesophagus, stomach, intestine, colon/rectum) are discussed. The pathophysiology of this type of metastasis explains the radiologic images obtained during barium transit examinations. The lymphatic type of spread observed in the oesophageal region in connection with carcinoma of the breast is the origin of stenosis of the middle third. The haematogenous type of diffusion encountered during melanomas creates intramural or intraluminal radiologic images. Two means of spread can be observed in the stomach. Haematogenous spread can result in frequently multiple and ulcerated nodular submucosal lesions from melanomas and bronchogenic carcinomas; it can also cause a more or less stenotic invasive image, especially in connection with carcinoma of the breast. Dissemination by means of the mesenteric reflections, and in particular around the gastrocolic ligament, explains the spread of a carcinoma of the transverse colon towards the stomach. The most frequent secondary sites in the gastrointestinal tract occur in the small intestine, the majority of these metastases being caused by pelvic tumours. Whether occurring in the small intestine or the colon, the pathophysiology is similar: direct invasion by a non-contiguous primary carcinoma along the fascias and mesenteric attachments (more rarely by lymphatic permeation), dissemination by the peritoneal fluid or haematogenuous spread. In the first two types of dissemination cited, the image encountered is often hard to differentiate from radiation-induced lesions.