KRAS mutational analysis in ductal adenocarcinoma of the pancreas and its clinical significance

Pathol Res Pract. 2014 May;210(5):307-11. doi: 10.1016/j.prp.2014.01.011. Epub 2014 Feb 12.

Abstract

Mutations of KRAS are detectable in 70-90% of pancreatic duct adenocarcinomas (PDAC), using direct sequencing. We used a highly sensitive molecular method in order to investigate: (a) the frequency and prognostic significance of different KRAS mutations and, (b) whether the presence of KRAS mutations in histologically-negative resection margins of PDAC could explain local tumor recurrence after surgery. Twenty-seven patients with histologic diagnosis of PDAC, radical pancreaticoduodenectomy and histologically-negative margins were evaluated. KRAS mutations were searched for mutant-enriched PCR in tumor and negative resection margins. KRAS mutations were detected in 85.2% of the cases; the most frequent mutation was G12D (48.1%). Shorter OS was found in patients with G12D (25 months; 95% CI, 20.5-29.5), vs patients with other mutations (31.5 months; 95% CI, 25.6-37.1) (N.S.). KRAS mutation in histologically-negative margins was detected in one patient who died of locoregional recurrence; six patients had tumor recurrence but no mutations in surgical margins. The high frequency of KRAS mutations suggests a search for KRAS status to improve the diagnosis in suspected cases; the G12D mutation could be related to poor prognosis, but without statistical significance. No correlation was found between the frequency of cancer recurrence and KRAS mutations in surgical margins.

Keywords: Adenocarcinoma; KRAS mutations; Pancreas.

MeSH terms

  • Aged
  • Aged, 80 and over
  • Carcinoma, Pancreatic Ductal / genetics*
  • Carcinoma, Pancreatic Ductal / mortality
  • Female
  • Genes, ras / genetics*
  • Humans
  • Male
  • Middle Aged
  • Mutation / genetics*
  • Neoplasm Recurrence, Local / genetics*
  • Neoplasm Recurrence, Local / mortality
  • Pancreas / pathology
  • Pancreatic Neoplasms / genetics*
  • Pancreatic Neoplasms / mortality
  • Prognosis