The objective of this study was to investigate the immunophenotype of T-lineage
acute lymphoid leukemia (
T-ALL) and to find valuable
immunologic markers in
T-ALL diagnosis and
therapy. Four-color multiparametric flow cytometry(FCM) with CD45/SSC gating was used for immunophenotyping of 95 patients with newly diagnosed
T-ALL. The results demonstrated that
T-ALL occurred more frequently in males younger than 30 years of age and was usually accompanied by a high WBC count and
tumor mass at diagnosis. Univariate analysis showed an influence on achievement of CR1 for age (< 30 years) but not for WBC count and
tumor mass. According to WHO (2008) classification of
tumors of haematopoietic and lymphoid tissues, 87 patients with confirmed subtype included 27 cases of Pro-
T-ALL (31.0%), 31 cases of Pre-
T-ALL (35.6%), 23 cases of cortical-
T-ALL (26.4%), 6 cases of medullary-
T-ALL (6.9%). CD34 expression in Pro-
T-ALL was significantly higher than that of Pre-
T-ALL (p = 0.001). After the first
chemotherapy, the complete remission rate in Pro-
T-ALL was statistically lower than that of Pre-
T-ALL. Besides, the complete remission rate of immature
T-ALL (including Pro-
T-ALL and Pre-
T-ALL) was also significantly lower than that in mature
T-ALL (including cortical-
T-ALL and medullary-
T-ALL). Myeloid
antigen (CD13, CD33) expression was associated with
T-ALL subtype and treatment effect. While 66.7% of CD13(+) patients belonged to Pre-
T-ALL, most (60.0%) of CD33(+) patients were classified into Pro-
T-ALL; CD13 expression had no effect on CR1 rate whereas CD33(+) patients had worse treatment effect compared with CD33(-) groups (p = 0.001). Notably, the expression of CD117 reached up to 26.7% and the positive cases were primarily distributed in pro-T-TAll and pre-
T-ALL. It is found that CD117 expression in CD34(-) group was homogeneous and CD117 expression level was less than 10% in 73.2% patients, but CD117 expression level in CD34(+) group was not homogenous, in which group the CD117 expression levels < 10%, 10% - 20% and > 20% were 44.2%, 17.3% and 38.5% respectively. As compared with CD34(-) group, the proportion of patients with CD117 expression levels < 10%, > 20% in CD34(+) group was higher, and there was significant difference between these 2 group. It is concluded that immunophenotype has great value in
T-ALL diagnosis, classification as well as treatment. Flow cytometry provides access to find valuable
immunologic markers for
T-ALL biological research.