We analyzed the clinicopathologic characteristics of 136 intestinal diffuse large B-cell lymphomas (DLBCLs) among 126 patients. The DLBCL sites were categorized as: duodenum (n = 23), ileocecal region (n = 63), other small intestine (n = 29), rectum (n = 7), and other large intestine (n = 14). Patients with DLBCLs of the ileocecal region or other small intestine frequently underwent surgery for ileus or perforations (P < 0.001), were predominantly male (P = 0.042), and had a higher incidence of limited-stage disease (P = 0.001), lower International Prognostic Index (P = 0.015), and lower incidence of lactate dehydrogenase elevation (P = 0.007) than those with DLBCLs of other regions. Half of the intestinal DLBCLs exhibited the germinal center B-cell phenotype. A low-grade B-cell lymphoma background was found in 21% of the cases; the prevalence was significantly lower in the ileocecal region (13%, P = 0.025), suggesting a higher incidence of de novo DLBCLs. Intestinal follicular lymphoma (FL) and mucosa-associated lymphoid tissue (MALT) lymphoma backgrounds were observed in 10% and 0% of the cases, respectively. Five percent (5/107) of intestinal DLBCL cases were Epstein-Barr virus-encoded RNA-1 positive. The clinicopathologic characteristics of the DLBCLs differed by region. Histologic transformation of intestinal FL was observed in around 10% of the intestinal DLBCL cases.
Keywords: Duodenum; Intestines; Large B-cell lymphoma; Non-Hodgkin; Pathology.