Korean J Hematol.  2007 Sep;42(3):250-257. 10.5045/kjh.2007.42.3.250.

FLT3 Internal Tandem Duplication in Acute Myeloid Leukemia with Normal Karyotype

• Kim SH
• Kim YK
• Lee IK
• Jo DY
• Won JH
• Kwak JY
• Yim CY
• Park MR
• Yang DH
• Cho SH
• Lee JJ
• Chung IJ
• Kim HJ

• KMID: 2305200
• DOI: http://doi.org/10.5045/kjh.2007.42.3.250

Abstract

BACKGROUND: The presence of FLT3 internal tandem dupulication (FLT3/ITD) in patients with acute myeloid leukemia (AML) with normal karyotype was investigated in order to evaluate its clinical and prognostic significance.
METHODS
The FLT3/ITD was studied by PCR assay in bone marrow samples obtained from 123 patients at diagnosis. Ninety patients who received intensive induction chemotherapy were evaluated.
RESULTS
Of total 123 patients, forty-seven (38.2%) demonstrated the aberrant FLT3/ITD. Patients with FLT3/ITD had significantly higher leukocyte counts at presentation than did patients without FLT3/ITD (P=0.04). By multivariate analysis, the FLT3/ITD was an independent prognostic factor of leukemic-free survival (LFS) (P=0.01) in AML patients with normal karyotype.
CONCLUSION
This study demonstrated that the presence of the FLT3/ITD was a significant factor for poor prognosis in AML patients with normal karyotype.

Keyword

FLT3/ITD; Acute myeloid leukemia; Normal karyotype

MeSH Terms

Bone Marrow
Diagnosis
Humans
Induction Chemotherapy
Karyotype*
Leukemia, Myeloid, Acute*
Leukocyte Count
Multivariate Analysis
Polymerase Chain Reaction
Prognosis

Figure

• 

  Fig. 1 PCR products of the FLT3/ITD, analyzed by gel electrophoresis. Reverse view of ethidium-bromide-stained 6% polyacrylamide gel. FLT3/ITD was detected as extra-bands in addition to normal band of 328 bp. Lanes 1 to 7 show PCR results in seven patients with FLT3/ITD. M: molecular weight markers, WT: wild type.

• 

  Fig. 2 Overall survival (OS) (upper panel) and leukemic-free survival (LFS) (lower panel) of AML patients with normal karyotype before transplantation. A trend for longer survival was observed in patients without FLT3/ITD compared with those with FLT3/ITD, but there was no statistical significance. A significant difference in LFS was found between FLT3/ITD-positive and FLT3/ITD-negative patients (OS: P=0.16; LFS: P=0.01 by the log rank test with pooled over strata).

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