A 63-year-old woman presented with a high WBC count and splenomegaly, but no lymphadenopathy. A bone marrow biopsy showed a subset of the neoplastic cells appear positive for SOX11, focal positive for CD5, negative for cyclin D1 and LEF1 and flow was negative for CD200. The overall clinical, morphologic, and immunophenotypic findings are atypical for either CLL or MCL (Figure 1A, 1B, and 1C). FISH was normal for the CLL panel and the CCND1 and IGH gene regions (Figure 1C).
The correct answer is ...
CCND2 FISH probe to rule in a possible cyclin D1-negative MCL.
It is reported that CCND2 rearrangements are the most frequent genetic events in cyclin D1-negative MCL. Therefore, FISH for CCDN2 would be the next best step to clarify the diagnosis.
Alaa Koleilat, Ph.D.
Fellow, Laboratory Genetics & Genomics
Xinjie Xu, Ph.D.
Consultant, Laboratory Genetics & Genomics
Assistant Professor of Laboratory Medicine and Pathology
Mayo Clinic College of Medicine and Science