Metastatic colorectal cancer KRAS genotyping in routine practice: results and pitfalls.

摘要: KRAS genotyping is mandatory before anti-epidermal growth factor receptor monoclonal antibody therapy in metastatic colorectal cancer, which the second leading cause of cancer-related death United States and Europe. Thus, large-scale mutation screening needed for efficient patient management future cancer might also include detection BRAF V600E mutation, a very strong negative prognostic cancer. We report our experience routine KRAS/BRAF practice performed on 1130 formalin-fixed paraffin-embedded tumor samples from 992 patients. DNA was extracted macrodissected areas highlighted by pathologist, codons 12/13 mutations were assessed single SNaPshot® multiplex assay each confirmed an independent analysis. were, respectively, present 41.8 6.5% samples. If mutually exclusive, four presented two concomitant mutations. Genotyping paired primary tumors metastases 44 patients indicated that 5 (11.4%) discordant mutational status. genotype heterogeneity observed within sites seven cases. Non-reproducible artefactual detected 53 (4.7%). found prominent mechanism to these fragmentation occurring during tissue processing. Routine tissues requires, therefore, development quality control scheme molecular pathology, especially because damages induced formalin fixation. The some indicates it should be more appropriate perform if sample available.