title: KRAS mutation testing of metastatic colorectal cancer in Australia: where are we at?
abstract: OBJECTIVE
  To carry out a nationwide study of KRAS testing in metastatic colorectal cancer as reported by nine major molecular pathology service providers in Australia, including mutation frequencies and turnaround times that might impact on patient care.
  
  
  METHODS
  Participating laboratories contributed information on KRAS mutation frequencies, including the G13D mutation type, as well as turnaround times for tumor block retrieval and testing.
  
  
  RESULTS
  The KRAS mutation frequency observed by nine different test sites for a total of 3688 metastatic colorectal cancers ranged from 34.4% to 40.7%, with an average across all sites of 38.8%. The average frequency of the G13D mutation type among all cases was 8.0%. The median turnaround time was 17 days (range 0-191), with 20% of cases requiring more than 4 weeks for a KRAS test result. The major contributor to long turnaround times was the time taken to retrieve archived blocks of primary tumor, particularly from sources external to the test site.
  
  
  CONCLUSIONS
  The frequency of KRAS mutations in metastatic colorectal cancer reported by the major Australian test sites is very similar to that reported by other large overseas studies. More widespread introduction of routine testing at the time of initial diagnosis should eliminate the long turnaround times currently being experienced in a significant proportion of cases. Future expansion of testing to include other KRAS and NRAS mutation hotspots may spur the introduction of next-generation sequencing platforms.
authors.affiliation: Hunter Area Pathology Service, Newcastle, New South Wales, Australia.
authors.forename: Rodney J
authors.initials: RJ
authors.lastname: Scott
authors.forename: Stephen B
authors.initials: SB
authors.lastname: Fox
authors.forename: Jayesh
authors.initials: J
authors.lastname: Desai
authors.forename: Fabienne
authors.initials: F
authors.lastname: Grieu
authors.forename: Benhur
authors.initials: B
authors.lastname: Amanuel
authors.forename: Kerryn
authors.initials: K
authors.lastname: Garrett
authors.forename: James
authors.initials: J
authors.lastname: Harraway
authors.forename: Glenice
authors.initials: G
authors.lastname: Cheetham
authors.forename: Neville
authors.initials: N
authors.lastname: Pattle
authors.forename: Afaf
authors.initials: A
authors.lastname: Haddad
authors.forename: Keith
authors.initials: K
authors.lastname: Byron
authors.forename: Barney
authors.initials: B
authors.lastname: Rudzki
authors.forename: Paul
authors.initials: P
authors.lastname: Waring
authors.forename: Barry
authors.initials: B
authors.lastname: Iacopetta
mesh_terms: D001315:Australia; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000473:pathology; D011905:Genes, ras; D005820:Genetic Testing; D006801:Humans; D009154:Mutation; D009362:Neoplasm Metastasis; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D016283:Proto-Oncogene Proteins p21(ras); D018631:ras Proteins / Q000235:genetics*
chemical_list: C117307:KRAS protein, human; D011518:Proto-Oncogene Proteins; D016283:Proto-Oncogene Proteins p21(ras); D018631:ras Proteins
keywords: Group 1: major specialty; Group 2: tumor type; Group 3: other specific research area; biomarker; colorectal; gastrointestinal cancer; pathology