The accuracy of fine needle aspiration cytology and flow cytometry in evaluation of nodal and extranodal sites in patients with suspicion of lymphoma.

Today lymphomas are defined according to a combination of morphology, immunophenotype, genetic features and clinical presentation, so beside the pure cytomorphologic analysis in diagnosis of lymphoma ancillary techniques such as cytochemistry, immunocytochemistry, molecular diagnosis and flow cytometry (FC) are often used. Our goal was to determinate how is information given by fine-needle aspiration cytology (FNAC) and FC correlated with pathohistologic diagnosis and to evaluate ability to diagnose and subclassify malignant lymphomas by FNAC and FC. This study is a retrospective chart review of patients with suspicion of lymphoma processed at University Hospital Dubrava in Zagreb. After analysis 50 patients fulfilled inclusion criteria for this study (FNAC diagnosis with or without FC and consecutive confirmatory pathohistological diagnosis). When analyzing accuracy of FNAC according to suspicion of lymphoma or NHL and differential diagnosis lymphoma sensitivity was 97.7%, specificity 85.7% and the diagnostic accuracy was 96%. When analyzing accuracy of FNAC according to the subclassification of lymphoma, sensitivity was 74.4%, specificity 85.7% and the diagnostic accuracy 76%. Combined FNAC and FC improved sensitivity, positive predictive value, negative predictive value and diagnostic accuracy. Sensitivity was 79.1% and the diagnostic accuracy 80%. We have shown that these methods can distinguish benign lymphadenopaties from lymphomas and also subclassify lymphomas and quickly provide clinicians with that information.