Endoscopic manifestations of primary colorectal lymphoma.

Background/Aims: Little is known about the endoscopic manifestations of primary colorectal lymphoma. The study was designed to describe the features of colonoscopy and endoscopic ultrasonography of primary colorectal lymphoma. Methodology: twenty-five patients with a definite diagnosis of primary colorectal lymphoma were recruited in this study. Their colonoscopic and endoscopic ultrasonography manifestations were retrospectively reviewed. Results: Based on colonoscopic features, primary colorectal lymphomas were classified into three subtypes: ulcerative type (n = 16, 64%), polypoid type (n = 4, 16%), and massive type (n = 5, 20%). Thirteen (92.9%) of the 14 patients with T-cell lymphomas presented as ulcerative lesions, and 3 (27.3%) of the 11 patients with B-cell lymphomas presented as ulcerative lesions (92.9% vs. 27.3%, p = 0.002). The initial diagnose accordance rate of colonoscopy was only 28% for primary colorectal lymphomas. The endosonography features of primary colorectal lymphomas included disappearance of normal colorectal layers, diffuse hypoechoic lesions instead, and thickening of intestinal wall. Conclusions: Primary colorectal T-cell lymphoma presented as ulcerative lesions more frequently than B-cell lymphoma. It was difficult to differentiate primary colorectal lymphoma from other diseases merely based on colonoscopy. Endoscopic ultrasonography was useful in the diagnosis of primary colorectal lymphoma.