Evaluation of Intratumoral HER-2 Heterogeneity by Fluorescence In Situ Hybridization in Invasive Breast Cancer: A Single Institution Study.
10.3346/jkms.2011.26.8.1001
- Author:
Sarah LEE
1
;
Woohee JUNG
;
Soon Won HONG
;
Ja Seung KOO
Author Information
1. Department of Pathology, Yonsei University College of Medicine, Seoul, Korea. kjs1976@yuhs.ac
- Publication Type:Original Article ; Evaluation Studies
- Keywords:
Breast Neoplasms;
HER-2;
Gene Heterogeneity;
In Situ Hybridization, Fluorescence
- MeSH:
Adult;
Breast Neoplasms/*genetics/pathology;
Chromosomes, Human, Pair 17;
Female;
Genetic Heterogeneity;
Humans;
In Situ Hybridization, Fluorescence/*methods;
Middle Aged;
Receptor, erbB-2/*genetics/metabolism;
Retrospective Studies
- From:Journal of Korean Medical Science
2011;26(8):1001-1006
- CountryRepublic of Korea
- Language:English
-
Abstract:
This study aimed to determine the incidence and characteristics of HER-2 gene heterogeneity in invasive breast cancer in a single institution. Included were 971 cases of primary invasive breast cancer diagnosed between 2008 and 2010. Fluorescence in situ hybridization (FISH) image files were retrospectively reviewed and HER-2 gene heterogeneity was defined as more than 5% but less than 50% of analyzed invasive tumor cells with a HER-2/Chr17 ratio higher than 2.2, according to the College of American Pathologists guidelines. HER-2 gene heterogeneity was identified in 24 (2.5%) cases. The mean proportion of invasive tumor cells with a HER-2/chromosome 17 ratio higher than 2.2 was 11.6% (range: 5%-25%). Of 24 cases, HER-2 gene status was not amplified in 8, showed borderline amplification in 2, and amplification in 14. All HER-2 amplification cases were low-grade. In conclusion, HER-2 gene heterogeneity of invasive breast cancer is identified in routine FISH examination. This may affect the results of HER-2 gene amplification status in FISH studies.
