Mutations in TP53, PIK3CA, PTEN and other genes in EGFR mutated lung cancers: Correlation with clinical outcomes

Lung Cancer. 2017 Apr:106:17-21. doi: 10.1016/j.lungcan.2017.01.011. Epub 2017 Jan 25.

Abstract

Introduction: The degree and duration of response to epidermal growth factor receptor (EGFR) inhibitors in EGFR mutated lung cancer are heterogeneous. We hypothesized that the concurrent genomic landscape of these tumors, which is currently unknown in view of the prevailing single gene assay diagnostic paradigm in clinical practice, could play a role in clinical outcomes and/or mechanisms of resistance.

Methods: We retrospectively probed our institutional lung cancer database for tumors with EGFR kinase domain mutations that were also evaluated by more comprehensive molecular profiling, and evaluated tumor response to EGFR tyrosine kinase inhibitors (TKIs).

Results: Out of 171 EGFR mutated tumor-patient cases, 20 were sequenced using at least a limited comprehensive genomic profiling platform. 50% harbored concurrent TP53 mutation, 10% PIK3CA mutation, 5% PTEN mutation, among others. The response rate to EGFR TKIs, the median progression-free survival (PFS) to TKIs, the percentage of EGFR-T790M TKI resistance and survival had higher trends in EGFR mutant/TP53 wild-type cases when compared to EGFR mutant/TP53 mutant tumors (all p >0.05 without statistical significance); with a significantly longer median PFS in EGFR-exon 19 deletion mutant/TP53 wild-type cancers treated with 1st generation EGFR TKIs (p=0.035).

Conclusions: Concurrent mutations, specifically TP53, are common in EGFR mutated lung cancer and may alter clinical outcomes. Additional cohorts will be needed to determine if comprehensive molecular profiling adds clinically relevant information to single gene assay identification in oncogene-driven lung cancers.

Keywords: Adenocarcinoma; EGFR; Erlotinib; Kinase inhibitor; Lung cancer; Mutation; PIK3CA; PTEN; TP53.

MeSH terms

  • Adenocarcinoma / drug therapy
  • Adenocarcinoma / genetics
  • Adenocarcinoma / pathology
  • Adenocarcinoma of Lung
  • Antineoplastic Agents / pharmacology
  • Carcinoma, Non-Small-Cell Lung
  • Class I Phosphatidylinositol 3-Kinases / genetics*
  • Disease-Free Survival
  • Drug Resistance, Neoplasm
  • ErbB Receptors / antagonists & inhibitors
  • ErbB Receptors / genetics*
  • Erlotinib Hydrochloride / pharmacology
  • Humans
  • Lung Neoplasms / drug therapy
  • Lung Neoplasms / genetics*
  • Lung Neoplasms / pathology
  • Mutation*
  • PTEN Phosphohydrolase / genetics*
  • Phosphatidylinositol 3-Kinases / genetics
  • Protein Kinase Inhibitors / pharmacology
  • Retrospective Studies
  • Treatment Outcome
  • Tumor Suppressor Protein p53 / genetics*

Substances

  • Antineoplastic Agents
  • Protein Kinase Inhibitors
  • TP53 protein, human
  • Tumor Suppressor Protein p53
  • Erlotinib Hydrochloride
  • Phosphatidylinositol 3-Kinases
  • Class I Phosphatidylinositol 3-Kinases
  • PIK3CA protein, human
  • EGFR protein, human
  • ErbB Receptors
  • PTEN Phosphohydrolase
  • PTEN protein, human