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 × 109/l lymphocytes and 2% of samples with lymphocyte counts