Table 2.

Association of KRAS testing and treatment with EGFR inhibitors among patients with mCRCs

Treated with EGFR inhibitorsaNot treated with EGFR inhibitorsTotal
No KRAS test89 (35%)671 (72%)760 (64%)
KRAS testb163 (65%)265 (28%)428 (36%)
WT136 (83%)110 (42%)246 (57%)
Mutation25 (15%)152 (57%)177 (42%)c
Insufficient sample2 (1%)3 (1%)5 (1%)

Abbreviations: WT, wild-type genotype; mutation, any KRAS mutation for any codon tested, primarily codons 12 and 13 for most patients.

  • aPatient was treated with cetuximab or panitumumab at any time during the course of their clinical care.

  • bA KRAS test was ordered as part of the patient's clinical care. Insufficient sample = a test was ordered but no KRAS genotype was reported.

  • cAbout 40% had mutations in codon 12 or 13. An additional 2% had a mutation detected in codon 61. However, not all labs tested codon 61 as part of their KRAS sequencing protocol.