A 48-year-old woman presents with fatigue and recurrent infections. CBC shows WBC 85,000/μL with 70% medium-to-large lymphoid cells, Hb 9.8 g/dL, platelets 90,000/μL. Flow cytometry shows CD5+, CD19+, CD20+, CD23-, cyclin D1+, SOX11+. FISH shows t(11;14). What is the diagnosis?

• A Chronic lymphocytic leukemia (CLL) with Richter transformation
• B B-cell prolymphocytic leukemia
• C Marginal zone lymphoma
• D Mantle cell lymphoma in leukemic phase ✓

Explanation

Mantle cell lymphoma is characterized by t(11;14) producing cyclin B1 overexpression, with CD5+, CD23-, SOX11+ immunophenotype. It often presents in leukemic phase with marked leukocytosis. CLL is CD5+, CD23+, cyclin B1-. D-cell PLL is CD5 variable, CD23 negative, but lacks t(11;14) and cyclin B1. Marginal zone lymphoma is typically CD5 negative and lacks cyclin B1.

Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.