Primary colorectal lymphoma

PURPOSE: The purpose of this study was to review the clinical presentation and characteristics of primary colorectal lymphoma, analyze the prognostic factors, and assess the results of treatment with adjuvant chemotherapy. METHODS: We identified 37 cases at our institution between 1980 and 1996. They comprised 0.48 percent of all cases of colon malignancies (37/7,658) during this period. The following clinical information was obtained: age, gender, signs and symptoms, tumor site, tumor size, histology grade, pathology, and adjuvant chemotherapy. RESULTS: The most common presenting signs and symptoms were abdominal pain (62 percent), abdominal mass (54 percent), and weight loss (43 percent). The most frequent site of involvement was the cecum (45 percent). Histologically, 29 (78 percent) were classified as high-grade, and 8 (22 percent) as intermediate-grade-to-low-grade lymphoma. Nine (24.3 percent) of the cases were Stage EI, 23 (62.2 percent) were Stage EII, and 5 (13.5 percent) were Stage EIV. Twenty-one (57 percent) cases received adjuvant chemotherapy. The five-year survival rate was 33 percent for all patients and 39 percent for patients treated with combination chemotherapy. Overall median survival time was 24 months and 36 months for those with adjuvant chemotherapy. Only histology grade, among the factors examined, was a significant prognostic factor for survival. The mean survival time of the patients with Stage II disease who received chemotherapy was 117.4 months, and it was 47.9 months for the patients with Stage II disease who did not received chemotherapy. Conclusions: In our retrospective study high-grade lymphoma was the only significant adverse prognostic factor for survival. Receiving adjuvant chemotherapy significantly improved survival in patients with Stage II disease. Patients with diffuse large-cell type had better survival than patients with small noncleaved-cell type in Stage II high-grade lymphoma.