The role of flow cytometry in the diagnosis of non- Hodgkin's lymphoma, Hodgkin's lymphoma, granulomatous inflammation and reactive lymph node specimens.

PURPOSE In this study we aimed to compare the flow cytometry (FC) results of patients with B cell lymphoma, T cell lymphoma, Hodgkin's lymphoma, granulomatous inflammation and reactive lymph node and investigate the role of FC in malignant or non malignant conditions. METHODS Ninety patients were divided into 5 groups according to histopathology results. Patients were compared according to cytokeratin and positivity percentage of the following surface markers: CD45, CD19, CD5, CD19-CD5, CD4, CD8, CD3,CD16-CD56, CD10, CD10-CD19, CD23, CD20, CD4-CD8, CD3-CD16-56, CD30, CD38, kappa and lambda light chains, CD20-CD23. Patients were also compared according to the intensity of the expression (exp) of same markers. ROC curve analysis was performed for CD19+ cell percentage, CD38 exp, kappa/lambda and lambda/kappa ratios. RESULTS 1) Kappa/lambda and lambda/kappa ratios can distinguish B cell lymphoma from T cell lymphoma, Hodgkin's lymphoma, granulomatous inflammation and reactive lymph node; 2) CD19+ cell percentage can distinguish T cell lymphoma from Hodgkin's lymphoma, granulomatous inflammation and reactive lymph node; 3) CD38 exp can partly distinguish B cell lymphoma from T cell lymphoma, Hodgkin's lymphoma, granulomatous inflammation and reactive lymph node and T cell lymphoma from granulomatous inflammation, T cell lymphoma from reactive lymph node, Hodgkin's lymphoma from reactive lymph node. CONCLUSION Flow cytometry has a role in distinguishing lymphomas from non malignant lesions.