Reappraisal of HER2 Amplification in High-Grade Urothelial Carcinoma Based on 2018 ASCO/CAP Clinical Practice Guidelines.
Am J Clin Pathol
; 156(6): 1130-1141, 2021 Nov 08.
Article
em En
| MEDLINE
| ID: mdl-34124742
OBJECTIVES: To examine and compare human epidermal growth factor receptor 2 (HER2) amplification status in high-grade urothelial carcinoma (HGUCa), using both 2013 and 2018 HER2 reporting guidelines for breast carcinoma from the American Society of Clinical Oncology (ASCO)/College of American Pathologists (CAP). METHODS: HER2 status by fluorescence in situ hybridization (FISH) assay in 78 cases of HGUCa was compared using 2013 and 2018 HER2 reporting guidelines. RESULTS: HER2 amplification was observed in 22 (28.2%) of 78 tumors, of which 17 were in group 1, 1 in group 2, and 2 each in groups 3 and 4 (FISH assay, 2018). The remaining 14 HER2-amplified tumors (FISH assay, 2013) became negative, falling into group 2 (FISH assay, 2018) and were either negative or equivocal on immunohistochemistry (IHC, 2018). All FISH-negative tumors (nâ
=â
37) using 2013 criteria remained negative (group 5, 2018). FISH-equivocal tumors (2013) were further categorized into HER2 amplified (nâ
=â
1) and HER2 negative (nâ
=â
4) (2018). Overall, 20 (25.6%) tumors had discordant HER2 FISH results (2018 vs 2013). CONCLUSIONS: Implementing 2018 guidelines, HER2 amplification decreased from 36 to 22 cases. The group with a HER2/CEP17 ratio of 2 or more and average HER2 copy number less than 4 (group 2) were predominantly negative by IHC, suggesting a biologically distinct group of HGUCa that is different from HER2-amplified tumors, which may not respond to HER2-targeted therapy.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Neoplasias da Bexiga Urinária
/
Carcinoma de Células de Transição
Tipo de estudo:
Guideline
Limite:
Female
/
Humans
Idioma:
En
Revista:
Am J Clin Pathol
Ano de publicação:
2021
Tipo de documento:
Article
País de afiliação:
Índia