Validation of KRAS Testing for Anti-EGFR Therapeutic Decisions for Patients With Metastatic Colorectal Carcinoma

Context.-KRAS mutation status is a molecular marker for predicting patient response to treatment with anti-EGFR antibodies (cetuximab and panitumumab) in metastatic colorectal carcinoma. Different approaches may be taken to detect KRAS mutations. There currently are no US Food and Drug Administration-approved assays for the detection of KRAS mutations. For assays that are not approved by the US Food and Drug Administration, the performance characteristics of the assay must be determined and validated by the clinical laboratory before implementation. Objective.-To provide an example of how a KRAS mutation analysis assay may be validated in a clinical laboratory. Design.-Describing the approach used by an individual laboratory to compare different assays for validation of KRAS mutation analysis in metastatic colon carcinoma. Results.-Specific validation data are provided, illustrating how a laboratory established assay performance characteristics for KRAS mutation analysis. Conclusions.-All clinical laboratories must establish several performance specifications mandated by the Clinical Laboratory Improvement Amendments of 1988 before implementation of any laboratory-developed test. Approaches to the validation of such assays may vary among laboratories. We describe an approach used for validation of a KRAS mutation-analysis assay by one laboratory. (Arch Pathol Lab Med. 2012; 136: 26-32; doi: 10.5858/arpa.2011-0220-OA)