The role of KRAS mutation testing in the management of patients with metastatic colorectal cancer

Arch Pathol Lab Med. 2009 Oct;133(10):1600-6. doi: 10.5858/133.10.1600.


Context: KRAS mutations can be detected in approximately 30% to 40% of all patients with colorectal cancer. Several recent studies have shown that patients with KRAS mutations in codons 12 or 13 in metastatic tumors do not benefit from anti-epidermal growth factor receptor therapy with cetuximab or panitumumab.

Objective: To review the literature on the role of KRAS mutation testing for management of patients with metastatic colorectal cancer and to discuss testing strategies.

Data sources: This review is based on published, peer-reviewed literature; available information from medical organizations (eg, National Comprehensive Cancer Network, American Society of Clinical Oncology, College of American Pathologists); and information from clinical laboratories conducting KRAS mutation analysis.

Conclusions: Multiple methods for detecting KRAS mutations in colorectal tumors are available, and all methods in current clinical use appear to have adequate clinical sensitivity for predicting a lack of response to cetuximab and panitumumab. Pathologist expertise is essential to quality KRAS testing and to determining effective treatment for patients with metastatic colorectal cancer.

Publication types

  • Review

MeSH terms

  • Adenocarcinoma / drug therapy
  • Adenocarcinoma / genetics*
  • Adenocarcinoma / secondary
  • Antibodies, Monoclonal / therapeutic use
  • Antibodies, Monoclonal, Humanized
  • Antineoplastic Agents / therapeutic use*
  • Cetuximab
  • Colorectal Neoplasms / drug therapy
  • Colorectal Neoplasms / genetics*
  • Colorectal Neoplasms / pathology
  • DNA Mutational Analysis
  • DNA, Neoplasm / analysis
  • ErbB Receptors / antagonists & inhibitors
  • ErbB Receptors / drug effects
  • ErbB Receptors / metabolism
  • Humans
  • Mutation*
  • Panitumumab
  • Proto-Oncogene Proteins / genetics*
  • Proto-Oncogene Proteins p21(ras)
  • Randomized Controlled Trials as Topic
  • Signal Transduction / drug effects
  • ras Proteins / genetics*


  • Antibodies, Monoclonal
  • Antibodies, Monoclonal, Humanized
  • Antineoplastic Agents
  • DNA, Neoplasm
  • KRAS protein, human
  • Proto-Oncogene Proteins
  • Panitumumab
  • ErbB Receptors
  • Proto-Oncogene Proteins p21(ras)
  • ras Proteins
  • Cetuximab