Abstract
Introduction
Diagnosis of mature B-cells proliferations, especially those involving the spleen, do not always falls into any of the WHO types of B-cell neoplasms using standart diagnosis tools. This situation in notably encountered in the case of the differential diagnosis of marginal zone lymphoma (MZL), atypical chronic lymphocytic leukemia (aCLL), mantle cell lymphoma (MCL), and lymphoplasmacytic lymphoma (LPL), mostly due to the lack of immunological positive markers.
In order to find new markers to discriminate between these different malignancies, we have previously developed a proteomic strategy based on the analyses of plasma membrane microparticles and proposed two new specific markers: CD148 and CD1801,2 for MCL and MZL respectively. The simultaneous use of these two markers, together with the CD200 that is positive in most cases of CLL and negative in MCL could be of great interest to better assess the differential diagnosis.
Methods
Flow cytometry analyses have been realized in Nancy and Strasbourg hospitals by combining these three markers: CD148 (Clone 143-41 FITC); CD180 (Clone G28.8 PE) and CD200 (Clone OX104 APC).
Expression profile of these proteins was established on a well characterized set of patients (N=287): CLL with a Matutes score > 3 (N=81); MCL harboring t(11;14) translocation or CCND1 overexpression (N=44); LPL (N=58) classified following cytological morphology, IgM peak and the positivity of CD38 and/or Myd88 mutation, MZL (N=84), displaying a CD5- CD23- immunophenotype associated to a splenomegaly and 20 controls. For each group the mean of fluorescence intensity and Standard Error have been determined.
Results
MCL exhibited a strong expression of CD148 combined with a weak expression of CD180 and CD200. A weak expression of CD148 and CD180 coupled to a strong expression of CD200 was typical of the CLL group and a weak expression of CD148 and CD200 coupled to a strong expression of CD180 was observed in the MZL group. A moderate expression of these three markers was observed in the LPL group.
A threshold corresponding to MFI +/- 4 standard error was then calculated for each group, and patients were categorized following the expression profile of these 3 markers (see figures).
In this cohort, the above described profiles correctly identified MCL cases with a specificity of 92% and a sensitivity of 64%, aCLL cases with a specificity of 100% and a sensitivity of 47%, LPL cases with a specificity of 90% and a sensitivity of 54% and MZL cases with a specificity of 99% and a sensitivity of 60%.
Conclusion
These results strongly suggest that the incorporation of these three markers CD148 CD180 and CD200 in addition of the routinely used flow cytometry panel can be helpful in a number of cases for which the diagnosis is difficult.
References:
1) Miguet et al leukemia 2013
2) Miguet et al journal of proteome research 2009
No relevant conflicts of interest to declare.
