Several groups of putative response factors are discussed in the literature, including a proteomic spectra of blood serum samples [30], tumor mRNA expression biomarkers [31], transcriptome-based deduced activities of intracellular molecular pathways [32,33], EGFR expression level in tumors, and activating mutations of EGFR gene and of downstream regulatory kinases such as RAS family proteins and BRAF [34,35]. Here, EGFR is linked to neoplasm.