ABCB1 and Hand-foot syndrome: In the multivariate analysis, SNP rs2032582 in ABCB1 2677 TT, AT or GT genotypes and rs1800812 in PDGFRα GG genotype were significantly correlated with grade 2 and grade 3 HFS (odds ratio [OR] 6.6, 95% confidence interval [CI] 1.2–37, p = 0.03; OR 6.6, 95% CI 1.4–31.4, p = 0.02; respectively).