CD200 is a useful marker in the diagnosis of chronic lymphocytic leukemia. Issue 2 (16th October 2018)

• Record Type: Journal Article
• Authors: Mora, Alba; Bosch, Rosa; Cuellar, Carolina; Vicente, Eva Puy; Blanco, Laura; Martino, Rodrigo; Ubeda, José M.; Sierra, Jorge; Moreno, Carol; Nomdedeu, Josep
• Is Part Of: Cytometry. Volume 96:Issue 2(2019)
• Page Start: 143
• Page End: 148
• Publication Date: 2018-10-16
• Subjects: CD200 -- chronic lymphocytic leukemia -- immunophenotyping -- diagnostics -- flow cytometry; Flow cytometry -- Diagnostic use -- Periodicals; Cytodiagnosis -- Periodicals; 616.07582
• DOI: 10.1002/cyto.b.21722
• Languages: English
• ISSNs: 1552-4949

Abstract

Abstract : Background: The diagnosis of CLL is supported by a typical morphology and immunophenotype and usually does not present difficulties. Nevertheless, some patients with CLL can show an atypical phenotype, this raising the possibility of a lymphoproliferative disorder other than CLL. It has been recently shown that the expression of CD200 could be a rather consistent marker for CLL. Methods: The expression of CD200 was investigated in 120 consecutive patients with B‐cell chronic lymphoproliferative disorders (B‐CLPD) (65 cases diagnosed as typical CLL, 16 atypical CLL, and 39 non‐CLL before entering the study) by using multiparametric flow cytometry with four color combinations. CD200 was analyzed as percentage of positive cells (≥30%) and MFIR expression. ROC curves were used to determine the cut‐off for the CD200 MFIR. Matutes score (MS) was used as comparator. Results: All 81 (100%) patients classified as CLL and 25 of 39 (64.1%) classified as non‐CLL expressed high CD200 expression (≥30%). CD200 expression showed a high sensitivity (100%) and a low specificity (35.9%), and the accuracy was similar to that of Matutes score markers (range: 79.2%–86.7%); except SmIg that was 59.1%. The addition of CD200 to the Matutes score correctly identified 74 of 81 (91.4%) CLL cases including 9 of 16 atypical CLL cases. As per non CLL cases, 37 of 39 (94.9%) were correctly diagnosed by the modified system. Altogether, CD200 improved the diagnostic accuracy of Matutes score from 86.7% to 92.5% ( P < .01). Conclusion: These results show that CD200 is a valuable, albeit not specific, CLL diagnostic marker. © 2018 International Clinical Cytometry Society