[Exploration of tumor-like hyperplasia in extramedullary hematopoietic tissue of beta-thalassanemia patients].

To investigate the morphological features of mediastinal extramedullary hematopoietic tissue in beta-thalassanemia patients and its diagnosis, the morphological features of tumor-like hyperplastic in extramedullary hematopoietic tissue were analyzed by using fine needle aspiration cytological (FNAC) biopsy and compared with bone marrow smear sample. The results indicated that in the FNAC smears of mediastinal tumor, neutrophilic myelocyte, neutrophilic metamyelocyte, neutrophilic stab granulocyte and neutrophilic segmented granulocyte were observed in granulocytic series; early normoblast, polychromatic normoblast and orthochromatic normoblast were observed in erythrocytic series; and granular megakaryocyte, thromocytogenic megakaryocyte, scattered platelet and matured lymphocyte also were observed. Cell morphology and distribution in different stages were are similar to that in bone marrow smear, and these cells belong to the extra-medullary hemopoietic tissue. It is concluded that tumor-like hyperplasia in extra-medullary hemopoietic tissue of beta-thalassanemia patient is a rare phenomenon, FNAC detection is a quick, convenient and effective method for its diagnosis.