Epidermal growth factor receptor (EGFR) mutation can be expressed in a large proportion of non-small cell lung carcinomas (NSCLC). However, certain subtypes such as invasive mucinous adenocarcinoma of the lung can have very low expression.
The presence of this mutation can be assessed on biopsy samples. Epidermal growth factor receptor (EGFR) is a transmembrane glycoprotein that regulates signaling pathways to control cellular proliferation. It belongs to the erbB family of closely related receptor tyrosine kinases.
There is also some (but not 100% ) mutual exclusivity with ALK gene arrangements.
EGFR is not to be confused with the estimated glomerular filtration rate, which shares the same acronym but with a lower case "e": eGFR.
Useful for assessing the suitability of certain anti-cancer drugs (tyrosine kinase inhibitors) that inhibit EGFR such as gefitinib (Iressa) and erlotinib (Tarceva).