Morphologic, Immunophenotypic, and Cytogenetic Findings in 339 Patients with Acute Leukemia

Kim, Jong Phil; Cho, Duck; Kee, Seung Jung; Shin, Jong Hee; Suh, Soon Pal; Ryang, Dong Wook

Abstract

BACKGROUND: The findings from morphologic, immunologic, and cytogenetic studies have been used for diagnosis of acute leukemia. Although research regarding the relationship between each of these methods has grown significantly, the results of research in this area is still conflicting. Therefore, a comparative analysis of immunophenotyping results with the results of morphologic and cytogenetic analysis of 339 cases of acute leukemia was performed in this study.
METHODS
339 cases were chosen from the pool of patients with acute leukemia admitted to the Chonnam National University Hospital from July 1994 to December 2000 and comparative analysis was performed on the results of immunophenotyping using flow cytometry (Coulter EPICS XL Flow Cytometer) and morphological findings. Further comparative analysis was performed on 185 cases that also had available data from cytogenetic analysis.
RESULTS
Based on the FAB classification for the 339 cases with acute leukemia, 63.7% (216/339) was AML, 35.4% (120/339) was acute lymphoid leukemia (ALL), and 0.9% (3/339) was unclassified acute leukemia. In the AML cases, the CD13 and CD33 expression percentages were 90.0% (188/209) and 68.1% (141/207), respectively. HLA-DR expression percentages, with the exception of M3 and M3v, comprised 72.4% (118/163) and HLA-DR was expressed at 5.1% (2/39) in M3 and M3v. 85.6% (77/90) of B lineage ALL were CD10-positive. Ly+ AML were 18.6% (40/215) and My+ ALL were 35.5% (43/121). Among the cases with available cytogenetic analysis results, 56.3% (76/135) AML and 42.9% (18/42) ALL had evidence of chromosomal abnormalities.
CONCLUSIONS
Immunophenotyping results are generally consistent with the findings of morphological classifications and are useful in diagnosis of some subtypes of acute leukemia cases. However, many cases showed expression of unusual markers contrary to morphological diagnosis. Specific cytogenetic findings, t(8;21)(q22;q22), were observed, especially in CD19 and CD56 positive AML.