Ileo-Colonic Fistula Due to Diffuse Large B Cell Lymphoma: Unusual Presentation of a Rare Disease

Malignant ileocolonic fistulas have seldom been documented as complications of a primary gastrointestinal lymphoma (PGIL) such as aggressive diffuse large B cell lymphoma (DLBCL). These fistulas are frequently misdiagnosed due to the nonspecific clinical presentation. Currently, there is no standardized treatment approach, although a couple have been suggested with varying outcomes. We describe a case of DLBCL complicated with a malignant ileocolonic fistula in a 55-year-old male with a favorable outcome after surgery and chemotherapy.