From January 1974 to December 1990, 619 patients were submitted to surgical treatment for gastrointestinal carcinoma: 10 cases (1.61%) of non-Hodgkin's lymphomas were observed (4 of the stomach, 3 of the small intestine, 1 of the colon, 2 of the rectum). There were 5 men and 5 women, mean age 57.1 years (range 34-80). In 6 patients the diagnosis was performed with radiological investigations, in 4 with ultrasonography too. Endoscopy biopsy was unfit for diagnosis in the gastric localizations, while it was positive in both rectal localizations. Seven patients were operated and no postoperative morbidity or mortality was observed. The role of surgery is discussed, diagnosis for staging and therapy alone or associated with chemotherapy and/or radiotherapy.