Histological Diagnosis Following Radiological Suspicion: A Case of Chronic Lymphocytic Leukemia/Small Lymphocytic Lymphoma Masquerading as Duodenal Lesion

Chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) is a common leukemia characterized by monoclonal B-cell proliferation. Extramedullary and extranodal manifestations can occur either in association with systemic CLL or as isolated lesions. Gastrointestinal (GI) tract involvement, however, is uncommon. These patients may be asymptomatic or present with chronic diarrhea, abdominal pain, and gastrointestinal hemorrhage. The prognostic significance of extramedullary CLL remains a matter of debate, although the prognosis in these patients appears to be more favorable in the era of novel targeted drugs. Herein, the case of a patient with a prior diagnosis of CLL undergoing observational follow-up without active therapy, who was found to have duodenal involvement on a biopsy performed following persistent dyspeptic complaints. We highlight the importance of considering GI symptoms when selecting the most appropriate treatment regimen.