Kenhiro Rin

Expression of T‐cell‐associated antigens in B‐cell non‐Hodgkin's lymphoma

We performed the immunophenotyping of 101 patients with B‐cell non‐Hodgkins lymphoma (B‐NHL) using two‐colour flow cytometry (FCM) and found that lymphoma cells coexpressed at least one kind of T‐cell‐associated antigen (T‐Ag; CD2, CD5, CD7) in 25 patients (24·8%). Among these three T‐Ags, CD5 was the most frequently expressed, in 21 patients (20·8%), followed by CD7, expressed in five patients (5·0%), and CD2, which was expressed in two patients (2·0%). Two kinds of T‐Ag were simultaneusly expressed in three patients (CD2/CD5, CD2/CD7, and CD5/CD7, each expressed in one patient). Concerning the expression pattern of T‐Ag, there were no significant differences between lymph nodes and extranodal organs in the three patients with T‐Ag‐positive B‐NHL (T‐Ag(+) B‐NHL) who were analysed. When comparing the clinical features between T‐Ag(+) B‐NHL and T‐Ag‐negative B‐NHL (T‐Ag(–) B‐NHL), extranodal involvement and higher International Prognostic Index (H and H.I.) were significantly frequent in the former subgroup (P = 0·0119 and P = 0·0302 respectively).

Clinicopathological features of myeloid/natural killer (NK) cell precursor acute leukemia

Four patients (three males and one female) were diagnosed as myeloid/natural killer (NK) cell precursor acute leukemia in our department. Two patients showed the extramedullary involvement at initial presentation. Leukemic cells expressed CD7, CD33, CD45 and CD56 in all patients. Additionally, CD13, CD34, HLA-DR, cytoplasmic CD3 and myeloperoxidase were expressed in some patients. Trisomy 10 was found in two patients, which has not been reported in this disease. Therefore, myeloid/NK cell precursor acute leukemia might be rather heterogeneous especially in chromosomal abnormality though it seemed to constitute the distinct clinical entity among acute myeloid leukemia of M0 subtype.