A Case of Monomorphic Epitheliotropic Intestinal T-cell Lymphoma with a Clinical Presentation Similar to that of an Intrapelvic Cyst

Abstract

An 82-year-old woman presented with abdominal pain. Abdominal contrast-enhanced computed tomography (CT) done at another hospital to investigate the cause showed a cystic mass localized within the pelvic cavity. An intraperitoneal abscess due to gastrointestinal perforation was suspected, and she was transferred to our hospital for treatment. During surgery, rather than an intrapelvic abscess due to gastrointestinal perforation, it was found that the dilated small intestine had formed a massive cystic mass. Because this mass adhered tightly to the pelvic floor, as much of the small intestine as possible was resected. Immunostaining of the postoperative samples was CD3(+), CD4(-), CD5(-), CD7(+), CD8(+), CD20(-), CD56(-), and EBER in situ hybridization (-). Small to medium-sized atypical lymphoid cells were present throughout the entire thickness of the wall, and they showed comparatively monomorphic epitheliotropic proliferation and invasion in the mucosa, leading to a diagnosis of monomorphic epitheliotropic intestinal T-cell lymphoma (MEITL). The patient was discharged on postoperative Day 13 and underwent chemotherapy after discharge. However, she developed progressive disease 10 months postoperatively and was switched to best supportive care. She died of the original condition 12 months postoperatively.