Flow cytometry shows CD5+, CD20+(dim), CD23+, CD10−, cyclin D1−, surface IgM dim. This immunophenotype is most consistent with:
- A Chronic lymphocytic leukemia / small lymphocytic lymphoma ✓
- B Mantle cell lymphoma
- C Marginal zone lymphoma
- D Hairy cell leukemia
Correct answer: A. Chronic lymphocytic leukemia / small lymphocytic lymphoma
Explanation
CLL/SLL immunophenotype is CD5+, CD23+, CD20 dim, surface Ig dim, and cyclin D1 negative. Mantle cell lymphoma is also CD5+ but is CD23− and cyclin D1+ due to t(11;14). Marginal zone lymphoma is CD5−, CD23−. Hairy cell leukemia is CD25+, CD103+, CD11c+ and lacks CD5.
Reference: Robbins & Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.