Q: Given an abstract, generate a keyword (a noun phrase) that best describes the focus or contribution of the paper. Such keywords can be directly from the given abstract or outside it.
Abstract: During a 5-year period, 15 cases of primary gastrointestinal lymphoma, corresponding to 14% of the non-Hodgkin's lymphomas, were diagnosed in a population of 200,000. Most patients had a short duration of symptoms--less than 3 months--and a clinical picture dominated by abdominal pain. All patients were laparotomized and six patients presented with an acute abdomen and were subjected to emergency operations. In seven cases, gastrointestinal malignancy was not suspected preoperatively. The patients were treated with a combination of surgery, cytostatic therapy, and/or radiotherapy. Cases with localized disease had a favorable prognosis, seven of nine patients being alive 31 to 70 months after diagnosis. A statistically significant difference in median survival was also noted between patients with lymphomas of low-grade and high-grade malignancy (70+ vs. 10.5 months).
A:
Abdomen, Acute