 6. Absence of mutations in KRAS mutations in KRAS exon 2 codons 1213, exon 3 codons 5961 and exon 4 codon 117146, NRAS NRAS exon 2 codons 1213, exon 3 codons 5961 and exon 4 codons 117146, BRAF exon 15 codon 600 and PI3KCA in exons 9 and 20 