PRIMARY COLONIC LYMPHOMA - CLINICAL PRESENTATION, HISTOPATHOLOGIC FEATURES, AND OUTCOME WITH COMBINATION CHEMOTHERAPY

Primary colonic lymphomas are rare, but we identified 15 cases at our institution between 1973 and 1992. They comprised 5.8% of all cases of gastrointestinal lymphoma (15 of 259) and 0.16% of all cases of colon cancer (15 of 9,193) during the last 20 years. The most common presen ting symptoms were abdominal pain and weight loss (40% each). In seven patients (47%), a palpable abdominal mass was noted on the initial ph ysical examination. The most frequent site of involvement was the cecu m (73%). Histologically, six (40%) were classified as high-grade and n ine (60%) as intermediate-grade non-Hodgkin's lymphoma. The tumors usu ally presented at an advanced stage: in 13 of 15 patients (87%), the l ymphoma had spread to the adjacent mesentery, the regional lymph nodes , or both when first diagnosed. The 5-year survival rate was 27% for a ll patients and 33% (4 of 12) for patients treated with combination ch emotherapy. Two patients relapsed after 8 years of complete remission. Primary colonic lymphomas have an aggressive behavior and only a marg inal response to surgery and combination chemotherapy.