Background/aim: Monoclonal antibodies against epidermal growth factor receptor (EGFR) can extend progression-free survival (PFS) and overall survival (OS) in patients with unresectable colorectal cancer; however, skin toxicity often interferes with therapy continuation.
Patients and methods: We analyzed the polymorphisms in EGFR and IgG fragment C receptor (FCGR) genes and determined their associations with clinical outcomes including PFS, OS, and skin toxicity. Five polymorphisms in EGFR and FCGR genes in 32 patients with unresectable colorectal cancer who were treated with antibodies against EGFR were examined.
Results: Patients carrying the C/C genotype of the EGFR D994D polymorphism displayed significantly less skin toxicity than those with other genotypes, although no significant differences in PFS and OS were noted and no significant interactions were detected for other gene polymorphisms.
Conclusion: These results suggest that the EGFR D994D polymorphism is a useful biomarker for predicting the severity of skin toxicity in patients receiving antibody against EGFR.
Keywords: EGFR antibody; EGFR gene polymorphism; colorectal cancer; skin toxicity.