Performance of chromogenic in situ hybridization on testing HER2 Status in breast carcinomas with chromosome 17 polysomy and equivocal (2+) herceptest results: a study of two institutions using the conventional and new ASCO/CAP scoring criteria.
This study specifically addressed the performance of chromogenic in situ hybridization (CISH) on HER2 testing in 66 breast carcinomas with chromosome 17 polysomy and 49 carcinomas with an equivocal HercepTest (DakoCytomation, Carpinteria, CA) score by comparing CISH with corresponding FISH results at 2 test sites and evaluating intersite agreement of CISH results. For tumors with chromosome 17 polysomy, when using the manufacturers' criteria, the concordance values between CISH and FISH at site A, site B, and intersite CISH agreement were 95.8%, 95.5%, and 93.5%, respectively; when using the American Society of Clinical Oncology/College of American Pathologists (ASCO/CAP) criteria, the values were 100.0%, 100.0%, and 100.0%, respectively. For tumors with an equivocal HercepTest score, when using the manufacturers' criteria, the concordance values between the 2 methods at site A, site B, and intersite CISH agreement were 88.2%, 95.1%, and 91.1%, respectively; when using the ASCO/CAP criteria, the values were 96.7%, 97.3%, and 97.4%, respectively. These results indicate that CISH is reliable for testing these 2 types of tumors, especially when the ASCO/CAP criteria are used.
Gong
Yun
Y
Department of Pathology, Unit 53, The University of Texas M.D. Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX 77030, USA.
Sweet
William
W
Duh
Yi-Jing
YJ
Greenfield
Larry
L
Tarco
Emily
E
Trivedi
Smita
S
Symmans
W Fraser
WF
Isola
Jorma
J
Sneige
Nour
N
D001943:Breast Neoplasms / Q000235:genetics*; D002886:Chromosomes, Human, Pair 17; D005260:Female; D018734:Genes, erbB-2; D005821:Genetic Techniques / Q000592:standards; D006801:Humans; D007150:Immunohistochemistry; D017403:In Situ Hybridization / Q000379:methods* / Q000592:standards; D018719:Erb-b2 Receptor Tyrosine Kinases; D015203:Reproducibility of Results; D014314:Trisomy
D018719:Erb-b2 Receptor Tyrosine Kinases