A novel scoring system combining expression of CD23, CD20, and CD38 with platelet count predicts for the presence of the t(11;14) translocation of mantle cell lymphoma

Background: Both chronic lymphocytic leukemia (CLL) and mantle cell lymphoma (MCL) are CD5/19 positive. The t(11;14) MCL translocation is identified by fluorescent in situ hybridization (FISH) and can distinguish the two disorders. We attempted to identify flow cytometric and other markers predictive of a positive FISH test. Methods: We examined 100 atypical CLL/MCL cases for demographic, hematological, and cytometric variables, 96 were FISH tested for t(11;14) and four were known MCL. Results: Twenty‐two cases were confirmed as MCL. Multivariate analysis identified four variables associated with MCL: Thrombocytopenia (taken as Plt < 150 × 109/L), CD23 negative, CD20 strong, and CD38 positive, with these variables a four‐point score was devised. By ROC analysis, the MCL score was superior in differentiating MCL to the Marsden CLL score (AUC 0.95 vs. 0.78). MCL score ≥2 showed sensitivity 1, specificity 0.66, positive predictive value (PPV) 0.49, and negative predictive value (NPV) 1 for MCL. The score was then prospectively validated on an independent cohort of 44 cases of atypical CLL/MCL. No MCL had a score