Germline polymorphisms in the Fc gamma receptor (FCGR) gene have been reported to influence antibody-based cancer therapies. The FCGR StripAssay^® identifies the variants FCGR2A-H131R and FCGR3A-F158V.

FCGR

• Enhanced response to monoclonal antibody-mediated cancer therapies has been reported in several studies in patients carrying the higher-affinity FCGR2A-131His (rs1801274) or FCGR3A-158Val (rs396991) alleles.
• In colorectal cancer 56% of patients with FCGR3A-158 F/F genotype responded to treatment with cetuximab and bevacizumab, compared to 25% with heterozygous F/V and 8% with homozygous V/V genotype. Zhang et al., Anticancer Res. 2010 Oct;30(10):4209-17.
• Breast cancer patients with the genotypes FCGR2A-131 H/H and FCGR3A-158V/V responded favourably to trastuzumab therapy. Musolino et al., J Clin Oncol. 2008 Apr 10;26(11):1789-96.
• Although there is rising evidence that FCGR genotyping may help in treatment stratification, some studies show diverging results. Recommendations using FCGR polymorphisms for treatment decissions are currently not available. For a review see: Nagelkerke et al., Front Immunol. 2019 Oct 3;10:2237.