The followings conditions must be met for tumor response to EGFR-targeted therapies
1) KRAS (EXON 2) MUTATIONS DETECTION: no mutations present
2) BRAF (V600E) MUTATION DETECTION: no mutation present
3) PI3K (EXONS 9, 20) MUTATIONS DETECTION: no mutations present
4) EGFR expression: high expression
5) ERBB3 expression: normal expression (not overexpressed)
6) PTEN expression: normal expresssion (not deleted)