Utility of RARa Fluorescence In Situ Hybridization for Follow-up in Acute Promyelocytic Leukemia: Comparison with PML/RARa Fluorescence In Situ Hybridization.
- Author:
Kyoung Un PARK
1
;
Dong Soon LEE
;
Cha Ja SHE
;
Eun Kyong KO
;
Seonyang PARK
;
Han Ik CHO
;
Kyou Sup HAN
Author Information
1. Department of Clinical Pathology, Seoul National University College of Medicine, Seoul, Korea.
- Publication Type:Original Article
- Keywords:
RARa FISH;
RARa rearrangement probe;
PML/RARa FISH;
acute promyelocytic leukemia
- MeSH:
Bone Marrow;
Fluorescence*;
Follow-Up Studies*;
Gene Fusion;
Hematologic Neoplasms;
Humans;
In Situ Hybridization*;
Leukemia, Promyelocytic, Acute*
- From:Korean Journal of Clinical Pathology
2001;21(4):253-259
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
BACKGROUND: The most noted rearrangement identified in acute promyelocytic leukemia (APL) involves the PML and RARa genes, which results in the formation of the PML/RARa gene fusion. In the fluorescence in situ hybridization (FISH) for PML/RARa, the two signals may coincidentally overlap in normal nuclei. We investigated whether a new RARa rearrangement probe could discriminate the false-positive fusion signal of the PML/RARa translocation probe. METHODS: A total of 51 cases, which showed the results from 1% to the borderline level by PML/ RARa FISH, were re-tested with the RARa rearrangement probe. Also, we compared the RARa FISH with the PML/RARa FISH on 16 patients with newly diagnosed APL and performed the RARa FISH on 20 bone marrow specimens without hematologic malignancies in order to set up the cut-off value. RESULTS: The cut-off for the RARa FISH was determined as 1.02%. For patients with newly diagnosed APL, the PML/RARa FISH showed positive signals in 95.3+/-6.5% of the cells and RARa FISH showed positive signals in 97.0+/-7.0% (r=0.83). Of a total of 41 cases consisting of hematological disorders other than APL, five cases showed results equal to or greater than 5% with PML/RARa FISH and one case showed a positive result with RARa FISH. Of 10 follow-up APL cases, seven cases showed results equal to or greater than 5% with the PML/RARa FISH and four cases showed positive results with the RARa FISH. CONCLUSIONS: The cut-off value for the RARa FISH is 1.02% and we consider RARa FISH as the proper method for follow-up of APL.
