Droplet digital PCR measurement of HER2 in patients with gastric cancer

Br J Cancer. 2015 May 12;112(10):1652-5. doi: 10.1038/bjc.2015.129. Epub 2015 Apr 21.

Abstract

Background: Although there are some new criteria for human epidermal growth factor receptor 2 (HER2) expression with immunohistochemistry/fluorescence in situ hybridisation (IHC/FISH) in gastric cancer, the method is still ambiguous and is somewhat dependent on the subjective qualities of the evaluator.

Methods: We used droplet digital polymerase chain reaction (ddPCR) to evaluate HER2 amplification in formalin-fixed and paraffin-embedded (FFPE) samples and cell-free serum circulating tumour DNA (ctDNA) in 25 patients with gastric cancer.

Results: The concordance rate of HER2 amplification examined in FFPE samples with ddPCR and IHC/FISH was 92% (23 out of 25). The concordance rate of FFPE with ctDNA was not high (62.5%); however, patients who were HER2-positive by ctDNA had significantly shorter survival compared with HER2-negative patients.

Conclusions: Our results demonstrated that this ddPCR method was as effective as IHC/FISH and therefore might become a standard method for analysing not only FFPE but also ctDNA.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • DNA / blood
  • Female
  • Humans
  • In Situ Hybridization, Fluorescence / methods
  • Male
  • Middle Aged
  • Paraffin Embedding / methods
  • Polymerase Chain Reaction / methods
  • Receptor, ErbB-2 / genetics*
  • Stomach Neoplasms / blood
  • Stomach Neoplasms / enzymology*
  • Stomach Neoplasms / genetics*

Substances

  • DNA
  • ERBB2 protein, human
  • Receptor, ErbB-2