RESUMO
AIM: To assess the significance of the ITGB3 polymorphism at residue 33 (ITGB3 L33P) in the development of chronic oxaliplatin-induced peripheral neuropathy (OXLIPN). METHODS: Fifty-five patients with advanced colorectal cancer were genotyped, using allele-specific primers and sybr green in real-time PCR. Patients had received adjuvant oxaliplatin-based chemotherapy. The severity of the OXLIPN was defined by means of the clinical total neuropathy score (TNSc). Following the discontinuation of treatment, 34/55 patients (61.8%) developed OXLIPN. Grade I neurotoxicity was revealed in 13 (38.2%) patients and grade II neurotoxicity in 21 (61.8%) patients. RESULTS: Patients without OXLIPN (n = 21) were 19% homozygous for C, 33.3% were heterozygous, and 47.7% were homozygous for T. The corresponding percentages for patients developing any grade of OXLIPN (n = 34) were similar. About half of patients (46.1%) with grade I OXLIPN were heterozygotes (CT), 23.1% were CC, and 30.8% were TT. The majority of patients with grade II OXLIPN were TT (66.7%) with the remaining 33.3% being CT. The TT genotype was associated with increased severity of OXLIPN compared to the genotypes containing the C allele (P = 0.044). CONCLUSION: The ITGB3 L33P seems to be unrelated to the development of OXLIPN, but it appears to be related to its severity.