Immunophenotyping in systemic mastocytosis diagnosis: 'CD25 positive' alone is more informative than the 'CD25 and/or CD2' WHO criterion.
Aberrant expression of CD2 and/or CD25 by bone marrow, peripheral blood or other extracutaneous tissue mast cells is currently used as a minor World Health Organization diagnostic criterion for systemic mastocytosis. However, the diagnostic utility of CD2 versus CD25 expression by mast cells has not been prospectively evaluated in a large series of systemic mastocytosis. Here we evaluate the sensitivity and specificity of CD2 versus CD25 expression in the diagnosis of systemic mastocytosis. Mast cells from a total of 886 bone marrow and 153 other non-bone marrow extracutaneous tissue samples were analysed by multiparameter flow cytometry following the guidelines of the Spanish Network on Mastocytosis at two different laboratories. The 'CD25+ and/or CD2+ bone marrow mast cells' World Health Organization criterion showed an overall sensitivity of 100% with 99.0% specificity for the diagnosis of systemic mastocytosis whereas CD25 expression alone presented a similar sensitivity (100%) with a slightly higher specificity (99.2%). Inclusion of CD2 did not improve the sensitivity of the test and it decreased its specificity. In tissues other than bone marrow, the mast cell phenotypic criterion revealed to be less sensitive. In summary, CD2 expression does not contribute to improve the diagnosis of systemic mastocytosis when compared with aberrant CD25 expression alone, which supports the need to update and replace the minor World Health Organization 'CD25+ and/or CD2+' mast cell phenotypic diagnostic criterion by a major criterion based exclusively on CD25 expression.
Instituto de Estudios de Mastocitosis de Castilla La Mancha, Hospital Virgen del Valle, Toledo, Spain.
José Mário T
JM
Morgado
Laura
L
Sánchez-Muñoz
Cristina G
CG
Teodósio
Maria
M
Jara-Acevedo
Iván
I
Alvarez-Twose
Almudena
A
Matito
Elisa
E
Fernández-Nuñez
Andrés
A
García-Montero
Alberto
A
Orfao
Luís
L
Escribano
D015415:Biomarkers / Q000032:analysis; D001856:Bone Marrow Examination; D018801:CD2 Antigens / Q000032:analysis*; D016009:Chi-Square Distribution; D005434:Flow Cytometry; D019983:Guideline Adherence; D006801:Humans; D016130:Immunophenotyping / Q000379:methods / Q000592:standards; D053645:Interleukin-2 Receptor alpha Subunit / Q000032:analysis*; D008407:Mast Cells / Q000276:immunology*; D034721:Mastocytosis, Systemic / Q000175:diagnosis* / Q000276:immunology; D015588:Observer Variation; D010641:Phenotype; D017410:Practice Guidelines as Topic; D011237:Predictive Value of Tests; D011379:Prognosis; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D013030:Spain; D014944:World Health Organization
D015415:Biomarkers; D018801:CD2 Antigens; C508017:IL2RA protein, human; D053645:Interleukin-2 Receptor alpha Subunit