Clinical Implication of CD33 or CD34 Expression in Childhood Acute Leukemia

Kim, Nam Kyun; Choi, Seong Yeol; Won, Sung Chul; Kwon, Seung Yeon; Han, Jung Woo; Lyu, Chuhl Joo

Abstract

PURPOSE: It has been thought that cluster of differentiation (CD) presented on the surface of leukemic blast associated with the prognosis in childhood acute leukemia. However, the relationship between CD33 or CD34 presentation on leukemic cells and the prognosis in childhood leukemia has not fully established.
METHODS
Seventy-six patients who were diagnosed with acute leukemia in the Department of Pediatrics, Yonsei University Medical Center were enrolled. All patients were analyzed retrospectively. CD33 expression in acute lymphocytic leukemia (ALL) as well as CD34 presentation in ALL and acute myeloid leukemia (AML) were analyzed. 3-year-event-free-survival (EFS) was calculated according to whether those antigens were expressed or not. Kaplan-Meier curve was generated to compare EFS. A P-value less than 0.05 were regarded as statistically significant.
RESULTS
Fifty-eight and eighteen patients were ALL and AML, respectively. EFS for ALL was 81+/-5.2% and EFS for AML was 61+/-11.5%. 3- year-EFS of AML with and without CD34 expression was 83.3+/-15.2% and 46.7+/-15.4%, respectively (P=0.164). In ALL, 3-year-EFS was 80.7+/-8.9% and 78.8+/-7.2% in group with CD34 negative and positive (P=0.998). 84.8+/-5.4% and 60+/-15.5% 3-year-EFS was shown in the ALL patient with CD33 present or absent (P=0.079).
CONCLUSION
According to data, expression of CD33 revealed relatively low EFS in ALL and CD34 expression of AML in children might contribute to decrease the rate EFS, however these findings were not statistically different. Also, there is no difference in EFS between CD34 expressing and non-expressing ALL. We conclude even though CD33 expression in ALL and CD34 expression in AML have a tendency to influence to poor prognosis, it is necessary to study a larger number of cohort for evaluation of relationship between CD33 present in ALL, CD34 present in AML and prognosis.