KRAS genotyping as biomarker in colorectal cancer: a comparison of three commercial kits on histologic material.

Background/aim: The crucial role of KRAS status in new colorectal cancer target therapy raises the issue regarding which testing method to use. This study analysed 112 formalin fixed, paraffin-embedded (FFPE) metastatic tissue samples using three different commercially available kits.
Patients and Methods: A group of 40 KRAS wild-type (wt), 40 codon 12-mutated and 32 codon-13 mutated samples, previously evaluated by real-time PCR (TheraScreen kit), used as reference method, were analysed by Ampli-set-K-RAS and K-RAS StripAssay kit (herein called kit A and B, respectively) based on two different technologies.
Results: The sensitivity of both kits was 92.5% for wt samples, 100% and 95.0% for kit A and B, respectively for samples mutated in codon 12. The specificity was 100% for both kits for all groups of samples. After a minor modification of the kit A method, its specificity reached 100%.
Conclusion: of low cost and easy to use, kit A may be suitable for use in a routine diagnostic setting.