RESUMEN
PURPOSE: Treatment with regorafenib, which inhibits vascular endothelial growth factor (VEGF) receptor, frequently results in hand-foot skin reaction (HFSR), requiring treatment discontinuation or dose reduction. In our prospective study of regorafenib on patients with metastatic colorectal cancer, 17% of patients developed grade 3 HFSR. Herein, we retrospectively examined genetic polymorphisms associated with regorafenib-induced severe HFSR. METHODS: To identify associated polymorphisms, exploratory whole-exome sequencing focusing on factors related to VEGF-mediated signaling pathways was first performed in seven patients each, with grade 3 HFSR and without HFSR. The identified HFSR-associated polymorphisms were analyzed in all the 40 patients. RESULTS: The genotype frequency of rs3025009 G/A or A/A in the gene encoding VEGF-A (VEGFA) in patients with ≥ grade 2 HFSR was significantly higher than in other patients (P = 0.0257, Pc = 0.0771 [Bonferroni correction]). The frequency of C-C motif of chemokine ligand 4-like 2 (CCL4L2) rs3744596 A/T or T/T in patients with grade 3 HFSR was significantly lower than in others (P = 0.00894, Pc = 0.0268). The combination of the risk genotypes VEGFA rs3025009 G/A or A/A and CCL4L2 rs3744596 A/A was significantly associated with a higher incidence of grade 3 (P = 0.000614, Pc = 0.00246) and a longer median progression-free survival (P = 0.0234) than others. CONCLUSIONS: These VEGF-related polymorphisms were found to be associated with HFSR and the survival benefits of regorafenib treatment. TRIAL REGISTRATION NUMBER AND DATE: UMIN000013939, registered on May 12, 2014, when 6 months after the approval by the Institutional Review Board of Showa University.
