CD200 is a useful marker in the diagnosis of chronic lymphocytic leukemia

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

Issue Highlights – September 2020

“…CD200 was highly informative in the differential diagnosis between CLL and mantle cell lymphoma; 95% of CLL patients were found to be CD200 positive while only 8% of mantle cell patient were CD200 positive. This agrees with other studies of CLL which have generally shown positivity rates for CD200 above 97% and almost universal negativity in mantle cell lymphoma (17,18). In other lymphoproliferative disorders, however they found CD200 to be suboptimal in the differential diagnosis.…”

Positive predictive value of CD200 positivity in the differential diagnosis of chronic lymphocytic leukemia

“…Forty‐three articles and meeting abstracts (Alapat et al, ; Arlindo, Marcondes, Fernandes, & Faulhaber, ; Aytan et al, ; Brunetti et al, ; Challagundla, Medeiros, Kanagal‐Shamanna, Miranda, & Jorgensen, ; D'Arena et al, ; Debord et al, ; Dorfman & Shahsafaei, ; El Desoukey, Afify, Amin, & Mohammed, ; El Din Fouad, Ibrahim, Abdel Aziz, & Ibrahim, ; Espinet et al, ; Falay et al, ; Fan et al, ; Fanoni et al, ; Favre et al, ; Hu et al, ; Köhnke et al, ; Lesesve et al, ; Mason, Pozdnyakova, Li, Dudley, & Dorfman, ; Miao et al, ; Miguet et al, ; Mongeau‐Marceau et al, ; Montesdeoca et al, ; Mora et al, ; Palumbo et al, ; Pillai et al, ; Poongodi, Varma, Naseem, Parveen, & Varma, ; Rahman et al, ; Rahman, Kumar, Gupta, Singh, & Nityanand, ; Rawstron et al, ; Rawstron et al, ; Rawstron et al, ; Sallam, Elsalakawy, El‐Sewefy, & Khattab, ; Sandes et al, ; Sorigue, Franch‐Sarto, Sarrate, & Junca, ; Sorigue, Juncà, et al, ; Sorigue, Junca, & Granada, ; Sorigue, Raya, et al, ; Spacek et al, ; Starostka et al, ; Ting et al, ; van Dongen et al, ; Ye et al, ) were read in full, of which 16 were excluded (Figure S1). Therefore, 27 studies (5,764 patients) were included.…”

“…However, one study that used a higher fluorescence cutoff reported a suboptimal sensitivity for CLL (Lesesve et al, ). Similarly, two further studies (Fan et al, ; Mora et al, ) reported the necessary data to compare a standard threshold (any positivity) to a higher threshold. Both of them found a predictable loss of sensitivity and increase in specificity leading to a similar overall accuracy.…”

“…Given that the performance of a marker may vary across institutions based on the factors mentioned earlier, we provide a formula to determine PPV based on the disorders studied at each institution (prevalence) as well as the different cutoffs used (positivity rates). Assessment of CD200 within scores, as some authors have recently suggested (D'Arena et al, ; Köhnke et al, ; Mora et al, ), or in diagnostic algorithms, rather than in isolation, seems to be required.…”

Issue Highlights – March 2019

“…Mora and colleagues studied 120 consecutive patients with chronic B‐lymphoproliferations (81 within the CLL spectrum and 39 with other monoclonal B‐cell disorders) to establish whether CD200, a member of the Ig receptors membrane proteins superfamily, would have added value to the immunological scoring system already developed by Matutes et al . CD200 had already been suggested to be rather specific for B‐CLL in earlier studies.…”