Role of immunological lymphocyte subset typing as a screening method for lymphoid malignancies in daily routine practice.
BACKGROUND
The major diagnostic role of peripheral lymphocyte subset typing is to distinguish between malignant and reactive conditions.


METHODS
The present study evaluates the screening efficacy of flow cytometric lymphocyte subset typing for the presence of a lymphoid malignancy. Four hundred samples were analyzed with a combination of anti-T-, B-, and natural killer (NK)-cell monoclonal antibodies.


RESULTS
Two hundred and twenty (55%) samples showed a normal distribution of lymphocyte subsets, 73 (18%) samples exhibited unspecific alterations of lymphocyte subsets, 19 (5%) samples exhibited a reactive phenotype typical of Epstein-Barr virus/cytomegalovirus (EBV/CMV) infection, and 88 (22%) samples expressed a phenotype suggestive of lymphoma. The most predictive independent factor of a lymphoma-specific phenotype was the absolute lymphocyte count (P = 0.0001, odds ratio 73.225). Seventy-eight percent of samples containing >/=4 x 10(9)/l lymphocytes and 2% of samples with lymphocyte counts <4 x 10(9)/l exhibited a lymphoma-specific phenotype. The specificity of the referring clinical comment was the second best predictor of a lymphoma-specific typing outcome (P = 0.0001, odds ratio 19.589). The independent predictive values of lymphocyte morphology and of relative lymphocyte counts were of borderline significance.


CONCLUSIONS
The use of flow cytometric lymphocyte subset typing as a diagnostic screening method for lymphoma should be restricted to cases of unexplained elevation of absolute lymphocyte counts with or without morphological atypias and to cases with definite clinical symptoms of lymphoma.
Thalhammer-Scherrer
R
R
Department of Laboratory Medicine, University of Vienna, Vienna, Austria.
Veitl
M
M
Exner
M
M
Schneider
B
B
Geissler
K
K
Simonitsch
I
I
Schwarzinger
I
I
D003586:Cytomegalovirus Infections / Q000276:immunology; D003937:Diagnosis, Differential; D020031:Epstein-Barr Virus Infections / Q000276:immunology; D005434:Flow Cytometry / Q000379:methods; D019337:Hematologic Neoplasms / Q000175:diagnosis* / Q000276:immunology; D006801:Humans; D016130:Immunophenotyping; D018655:Lymphocyte Count; D016131:Lymphocyte Subsets / Q000276:immunology*; D008223:Lymphoma / Q000175:diagnosis* / Q000276:immunology; D008403:Mass Screening / Q000379:methods; D016017:Odds Ratio