[Malignant systemic diseases of the digestive tract].

In about 5-6% of all patients with malignant myeloproliferative disorders the gastrointestinal tract is involved with macroscopic lesions. The most common sites of digestive manifestations are stomach, small bowel, pancreas and colon. Multiple irregular ulcers, doughy infiltration of the bowel wall, multiple nodules and diffuse polyposis of the colon are classic patterns of secondary lymphoma of the gut. Prognosis is considerably impaired by gastroenterological symptoms.