Lung adenocarcinoma with EGFR amplification has distinct clinicopathologic and molecular features in never-smokers Academic Article uri icon

Overview

MeSH Major

  • Adenocarcinoma
  • Gene Amplification
  • Lung Neoplasms
  • Mutation
  • Receptor, Epidermal Growth Factor
  • Smoking

abstract

  • In a subset of lung adenocarcinomas, the epidermal growth factor receptor (EGFR) is activated by kinase domain mutations and/or gene amplification, but the interaction between the two types of abnormalities is complex and unclear. For this study, we selected 99 consecutive never-smoking women of East Asian origin with lung adenocarcinomas that were characterized by histologic subtype. We analyzed EGFR mutations by PCR-capillary sequencing, EGFR copy number abnormalities by fluorescence and chromogenic in situ hybridization and quantitative PCR, and EGFR expression by immunohistochemistry with both specific antibodies against exon 19 deletion-mutated EGFR and total EGFR. We compared molecular and clinicopathologic features with disease-free survival. Lung adenocarcinomas with EGFR amplification had significantly more EGFR exon 19 deletion mutations than adenocarcinomas with disomy, and low and high polysomy (100% versus 54%, P = 0.009). EGFR amplification occurred invariably on the mutated and not the wild-type allele (median mutated/wild-type ratios 14.0 versus 0.33, P = 0.003), was associated with solid histology (P = 0.008), and advanced clinical stage (P = 0.009). EGFR amplification was focally distributed in lung cancer specimens, mostly in regions with solid histology. Patients with EGFR amplification had a significantly worse outcome in univariate analysis (median disease-free survival, 16 versus 31 months, P = 0.01) and when adjusted for stage (P = 0.027). Lung adenocarcinomas with EGFR amplification have a unique association with exon 19 deletion mutations and show distinct clinicopathologic features associated with a significantly worsened prognosis. In these cases, EGFR amplification is heterogeneously distributed, mostly in areas with a solid histology.

publication date

  • November 2009

Research

keywords

  • Academic Article

Identity

Language

  • eng

PubMed Central ID

  • PMC2783286

Digital Object Identifier (DOI)

  • 10.1158/0008-5472.CAN-09-2477

PubMed ID

  • 19826035

Additional Document Info

start page

  • 8341

end page

  • 8

volume

  • 69

number

  • 21