#00063095

A 80-year-old man was admitted with fatigue, abdominal distention and lower extremity edema. He had extensive lymphadenopathy for 10 years without therapy. His haemoglobin concentration decreased from 123 to 74 g/L and serum lactate dehydrogenase (LDH) increased from 2236 to 7836 U/L in a week. The bone marrow aspirate showed 2 cell populations of small lymphocytes and atypical large cells with irregular nucleus and vacuoles in both cytoplasm and nucleus (panel A; original magnification×1000). Flow cytometry of both groinlymphnode (LN) and bone marrow aspirate demonstrated 2 different surface immunoglobulin restricted clonal B-cell populations: a small population was CD5+/dimλ+/CD19+/dimCD20+/dimCD22+/CD10-/CD43+/CD23-/FMC7-/CD38- (purple, panels B-C), and a larger population was CD5-/κ+/CD19+/CD20+/CD22+/FMC7+/CD23-/CD10-/CD38- (light blue, panels B-C). The LN biopsy showed effacement of the architecture by lymphoid infiltrate (panel D; original magnification ×100), which was CD20+ (panel E; original magnification×200)/CD21-/BCL6+/cyclinD1-/MUM1-/Ki-67(70%) (panel F; original magnification×200)/EBER(-). The overall findings are most compatible with the diffuse large B-cell lymphoma (DLBCL) arising through clonally-unrelated chronic lymphocytic leukemia/smalllymphocytic leukemia.

Clonally-unrelated Richter syndrome (RS) occurs in 10% to 20% of RS patients. Compared to the clonally-related RS, clonally-related RS cases carry better prognosis. So the earlier diagnosis through utilizing multiple tools is critical and may have somewhat improved outcomes.