A 55-year-old Japanese man presented with a fist-sized, nonremovable mass in the right lower abdomen. Transabdominal sonographic examination revealed extensive wall thickening without stratification in the distal ileum and cecum, whose echogenicity was homogeneous and extremely low. Some compressibility of the affected bowel was retained. Diagnostic findings obtained with other conventional modalities were consistent with intestinal malignant lymphoma. At surgery, 3 tumors were found in the ileocecal region and the ileum. Histopathological, immunophenotypic, and molecular cytogenetic analysis of resected specimens showed a diffuse Burkitt-like type of B-cell lymphoma.