Automated cellular imaging system III for assessing HER2 status in breast cancer specimens: development of a standardized scoring method that correlates with FISH.
The goal of this study was to assess the performance characteristics of the Automated Cellular Imaging System (ACIS III) for HER2 immunohistochemical analysis. The study was performed on 187 biopsy slides from patients who underwent HER2 testing between January and February 2008. Three scoring methods by the ACIS III were compared with the manual score and fluorescence in situ hybridization (FISH) results for HER2 amplification. The equal distribution score (EQD) method, in which 2 areas each of high-, moderate-, and low-intensity staining were measured, most closely matched the FISH HER2 amplification result. The numbers of immunohistochemically negative (0 or 1+)/FISH+ cases were equivalent for all methods. The EQD method had significantly fewer 2+ cases (n = 16) (P < .001) vs the manual method (n = 35) and yielded a higher positive predictive value (38%) for HER2 amplification compared with the manual method (20%). The EQD method may more accurately identify FISH-amplified HER2 cases with fewer 2+ cases that would be "reflexed" to FISH compared with the manual method.
Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN 55905, USA.
Douglas M
DM
Minot
Benjamin R
BR
Kipp
Renee M
RM
Root
Reid G
RG
Meyer
Carol A
CA
Reynolds
Aziza
A
Nassar
Michael R
MR
Henry
Amy C
AC
Clayton
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000378:metabolism; D001943:Breast Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology*; D004273:DNA, Neoplasm / Q000032:analysis; D005260:Female; D005784:Gene Amplification; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D007150:Immunohistochemistry; D017404:In Situ Hybridization, Fluorescence; D008875:Middle Aged; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism*; D015203:Reproducibility of Results; D012189:Retrospective Studies; D055815:Young Adult
D014408:Biomarkers, Tumor; D004273:DNA, Neoplasm; D018719:Erb-b2 Receptor Tyrosine Kinases; C508053:ERBB2 protein, human