Korean J Clin Pathol.  2000 Feb;20(1):1-6.

Analysis of Clonal Chromosome Abnormalities in Acute Myeloid Leukemia at Diagnosis, in Remission, and in Relapse

• Han JY
• Kim KH
• Lee YH
• Kim JS
• Kim HJ
• Lee EY

Abstract

BACKGROUND: Approximately two thirds of acute myeloid leukemia(AML) have recognizable clonal chromosome abnormalities. We have performed the cytogenetic monitoring of 35 de novo AML to follow the karyotype changes at diagnosis, in remission, and in first relapse.
METHODS
The study is based on 35 cases of AML seen between January 1, 1996 and June 30, 1999. They were subdivided in accordance with the FAB classification and treatment response was evaluated by the National Cancer Institute(NCI)-sponsored workshop criteria. Chromosome studies were done with standard 24-48 hour methotrexate synchronization.
RESULTS
The frequency of FAB M0, M1, M2, M3, M4, M5, and M6 was 1, 5, 18, 6, 3, 1, and 1, respectively. Clonal chromosome abnormalities were detected in 25 of 35(71%) in the decreasing order of t(8;21), t(15;17), +8, del(9q), etc. Thirty-one(89%) entered complete hematologic remission and 4(11%) represented partial remission. All 31 cases of complete remission had normal karyotypes. Three partial remission patients having both normal and abnormal metaphases at diagnosis and first follow-up had only normal cells after reinduction, however, in 1 case of induction failure, only abnormal metaphases persisted. In 5 of 7 relapses, karyotypes at diagnosis and relapse were identical. Two cases underwent a normal-to-abnormal change and clonal evolution, respectively.
CONCLUSIONS
In this study the karyotypes were normal during complete remission, and in relapse the original aberrations returned sometimes with newly acquired clonal abnormalities. Therefore, cytogenetic study yields basic important information for understanding of cancer genetic mechanisms and molecular biologic analysis.

Keyword

Acute myeloid leukemia; Clonal abnormalities; Cytogenetics

MeSH Terms

Chromosome Aberrations*
Classification
Clonal Evolution
Cytogenetics
Diagnosis*
Education
Follow-Up Studies
Humans
Karyotype
Leukemia, Myeloid, Acute*
Metaphase
Methotrexate
Recurrence*
Methotrexate