Changes of KRAS Exon 2 Codon 12/13 Mutation Status in Recurrent Colorectal Cancer

Ottó Dócs, Ferenc Fazakas, Nóra Lugosiné Horváth, László Tóth, Csilla András, Zsolt Horváth, Gábor Méhes

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5 Citations (Scopus)


Colorectal cancer (CRC) is a heterogeneous disease presenting with a wide spectrum of morphological and molecular characteristics sometimes even within the same patient. To understand the mechanisms of oscillations in the KRAS status we evaluated the collective of CRC patients tested using allele-specific PCR and Sanger-sequencing. Mutant KRAS allele was observed in 43.3 % of cases. Repeated analysis of KRAS status in recurrent tumors or metastases was performed in 18/665 cases and a total of 6 cases with different KRAS status was found. In three cases the histological pattern of the tumor was identical. In one patient different histology and molecular status was seen between the primary and the recurrent tumor samples. In two further cases localization, histological type and KRAS mutational status all supported the occurrence of synchron/metachron colorectal tumors. In conclusion, both the progression of the original disease but also multiple tumor formation may contribute to mutation status differences during the course of colorectal carcinoma.

Original languageEnglish
Pages (from-to)399-404
Number of pages6
JournalPathology and Oncology Research
Issue number2
Publication statusPublished - Apr 28 2015



  • Colorectal carcinoma
  • Heterogeneity
  • KRAS
  • Multiple tumors

ASJC Scopus subject areas

  • Pathology and Forensic Medicine
  • Oncology
  • Cancer Research

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