Abstract Richter syndrome (RS) is an uncommon but highly aggressive complication in patients with chronic lymphocytic leukemia (CLL), defined by histologic transformation, most frequently into diffuse large B-cell lymphoma (DLBCL). The cumulative risk of RS is estimated at 2–10% over the course of CLL, with an approximate annual incidence of 0.5–1%, and an overall poor prognosis. Gastrointestinal involvement is exceptional and may present with abdominal pain, anemia, or ulcerative endoscopic lesions, mimicking primary gastrointestinal disease and leading to diagnostic delays. Although rare, gastrointestinal involvement may represent a presenting feature of RS and should be considered in patients with abdominal symptoms associated with systemic findings or suggestive PET-CT abnormalities, as early recognition may facilitate targeted biopsy and expedite therapeutic decision-making. We report the case of a 54-year-old man with treated B-cell CLL who developed systemic and abdominal symptoms. PET-CT revealed hypermetabolic lymphadenopathy and wall thickening of the right colon and cecum. Colonoscopy showed involvement of the ileocecal valve with ulceration and infiltrative changes, and biopsy confirmed transformation to non–germinal center DLBCL with an immunophenotype consistent with RS. The clinical course rapidly deteriorated.
Carrasco et al. (Mon,) studied this question.