Primary malignant large bowel lymphoma.

Primary gastrointestinal (GI) lymphomas constitute about 5.6 per cent of total gut neoplasms. The involvement of large bowel as primary site is all the more rare. We carried out this study to evaluate the prevalence and clinicopathological features of large bowel lymphoma at Gujarat Cancer and Research Institute and to compare our findings with published literature. We carried out a retrospective analysis of the records of histologically diagnosed cases of large bowel lymphoma over a 5 year period. A total of eight cases of large bowel lymphoma were identified compared with 57 cases of primary GI lymphoma of other sites, constituting about 12.3 per cent (eight of 65) of all GI lymphomas. Peak incidence was observed in the second decade of life with a mean age at presentation of 30.6 years (range 4-70 years). A male-to-female ratio of one to two was observed. The most commonly presenting feature was altered bowel habits and diarrhea in more than 50 per cent of the patients. One patient presented with acute intestinal obstruction. Diagnosis was made by colonoscopic biopsies in all but one case. All of the patients were treated with surgery and adjuvant chemotherapy. A 4-year disease-free survival of 66.7 per cent was observed (95% confidence interval 0.05-1.28). There was no significant difference in survival in patients with high-grade versus low-grade tumors (50% vs 66.7%; P = 0.88) and stage of disease (75% vs 50%; P = 0.45) in stage II and III respectively. We conclude that large bowel lymphoma is a curable disease if treated aggressively. We suggest that all patients should be treated by primary surgery and should receive adjuvant chemotherapy.