Value of measuring subpopulations of T and B lymphocytes in patients with musculoskeletal tumours

Background Aims of our study were to assess the clinical value of measuring subpopulations of T and B lymphocytes in patients with musculoskeletal tumours as an immunodiagnostic procedure in the primary diagnosis of tumours. Methods In this prospective study, blood samples were obtained from 145 patients aged 04-98 years with musculoskeletal tumours. CD3, CD4, CD8, Helper/Suppressor ratio and CD19 subpopulations of lymphocytes were measured in specimens of whole blood in EDTA, upon the principle of Ortho Cytoron Absolute flow cytometry. Histological tumour diagnosis was obtained by the histopathology investigation of biopsy sample and lymphocytes values allocated accordingly. Results Out of 145 patients, osteomyelitis was diagnosed in 15 (10.34%). Median values of subpopulations of lymphocytes were: CD3 2456, CD4 1479, CD8 929, Helper/Suppressor ratio 1.8 and CD19 560 and all were raised above normal values in patients with osteomyelitis. Results were also calculated for osteosarcomas, Ewing sarcomas, giant cell tumours, chondrosarcomas and other tumours. These causes had median values within normal reference levels. To confidently out rule or confirm diagnosis of osteomyelitis, we measured the cut off point values and they were: CD3 2420, CD4 1400, CD8 873 and CD19 550. Conclusions The main clinical use of measuring subpopulations of lymphocytes is in establishing the correct diagnosis between suspected osteomyelitis and other musculoskeletal tumours. Levels of measured subpopulations of lymphocytes above the presented cut off values are important and accurate confirming factor for the clinical diagnosis of suspected osteomyelitis. Level of evidence II.