Intestinal Infiltration of Chronic Lymphocytic Leukemia/Small Lymphocytic Lymphoma Found on Screening Colonoscopy

B-cell chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) is a malignancy of dysregulated lymphocytes in bone marrow and lymphatics. Extra-nodal involvement has been previously cited to affect areas like the lungs, skin, central nervous system, and kidney. Gastrointestinal (GI) involvement in patients with chronic CLL/SLL is rare. We report a unique case of CLL/SLL found incidentally in a 71-year-old asymptomatic female undergoing a screening colonoscopy. Patients with GI infiltration of CLL/SLL may be asymptomatic like the patient described in this report, or present with symptoms that may resemble inflammatory bowel disease, microscopic colitis, or colon cancer. Therefore, it is important to remain vigilant for the occurrence of other malignancies during the follow-up of CLL/SLL patients.