Epidermal growth factor receptor (EGFR) gene encodes a membrane protein that plays a central role in transmitting signals that promote cell growth and proliferation. Its tyrosine kinase (TK) domain activates several downstream effectors that lead to the activation of the Ras-Raf-MAPK pathway. Overexpression of this gene as well as its oncogenic mutations that constitutively activate the TK domain of EGFR have been found in various solid tumors. Additionally, the excessive activation of EGFR has been associated with advanced stages of cancers as well as poor prognoses. This kit provides a ddPCR base assay that uses mutant-specific probes to identify the presence of EGFR mutations, including mutations on exon 18, exon 19, exon 20, and exon 21.