An 83-year-old woman visited our emergency department with a chief complaint of abdominal pain and vomiting. Abdominal computed tomography showed thickening of the wall of the small intestine in the right middle abdomen and marked bowel dilation and fluid retention in the oral side of the small intestine. The patient was diagnosed with adhesive bowel obstruction and hospitalized for conservative treatment. However, the treatment was unsuccessful, and laparoscopic surgery was performed. The intraoperative findings included thickening of the wall and hardening of the obstructed part, suggestive of an intestinal tumor; thus, this part was resected. A histopathological examination revealed diffuse infiltration of large-sized atypical lymphocytes in the tumor, and diffuse large B-cell lymphoma was diagnosed through immunochemical staining. The postoperative course was uneventful, and the lymphoma has not recurred. Intestinal malignant lymphoma rarely causes bowel obstruction without invagination. Here, we report this case and review the literature.
