Objective: To examine the immunophenotype of adult acute leukemia and analyze its clinical significance.
Methods: Immunophenotypes were examined by direct immunofluorescence method and flowcytometry in 69 de novo AL.
Results: 1. The incidence of myeloid antigen expression in 29 adult ALL was 30%. Among them, CD13 was 10.3% and CD33 was 20.7%, no difference was found in expression of myeloid antigens between B-ALL and T-ALL (P > 0.05). Myeloid antigens were expressed much more higher in CD34 positive ALL than in CD34 negative ALL (77.8% vs 13.3%, P = 0.036). CR rate in myeloid antigen positive ALL was lower than in myeloid antigen negative ALL (33.3% vs 80%, P = 0.0203). 2. The incidence of lymphoid antigen expression in 40 adult AML was 30%. Among them, CD7 was 15%, CD19 12.5% and CD2 2.5%. CD7 was mainly expressed in M1 and M2 subtypes. Lymphoid antigens were expressed higher in CD34 positive AML than in CD34 negative AML (61.1% vs 4.5%, P = 0.000125). Though CR rate was lower in lymphoid antigen positive AML than in lymphoid antigen negative AML, no significant difference between them was noted (50% vs 71.4%, P = 0.126).
Conclusion: Aberrant antigen expression in adult acute leukemia is about 30%. Antigen aberrant is much higher in CD34 positive AL than in CD34 negative AL. The CR rate of antigen aberrant AL is lower than that of usual AL.