RESUMO
PURPOSE: Chemotherapy-induced nausea and vomiting (CINV) can lead to a significant deterioration in the quality of life of cancer patients receiving chemotherapy. This study aimed to determine whether ABCB1 2677G > T/A was associated with complete response (CR; defined as no vomiting and no rescue medication) in acute phase (CR0-24), as well as to explore the genetic factors affecting delayed phase (CR24-120) CINV in cancer patients treated with a standard triple antiemetic regimen that included aprepitant. METHODS: This prospective single-center study included a total of 166 chemotherapy-naïve patients with breast cancer who received a standard dose of doxorubicin and cyclophosphamide combination chemotherapy; granisetron, dexamethasone, and aprepitant were administered prior to chemotherapy. CR0-24 was compared between minor allele homozygous (TT, AA, and TA) and major allele homozygous plus heterozygous (GG, GA, and GT) groups of ABCB1 2677G > T/A. In addition, 14 genetic polymorphisms were genotyped and their associations with CRs were investigated. RESULTS: The proportion of patients who achieved CR0-24, which was the primary endpoint of this study, was 59% in the minor allele homozygous and 61% in the major allele homozygous plus heterozygous groups of ABCB1 2677G > T/A. Although this difference was not statistically significant, multivariate logistic regression analysis adjusted for potential risk factors showed that TACR1 1323TT (OR, 2.57; P = 0.014) was a significant determinant of CR24-120. CONCLUSION: No significant association was found between ABCB1 2677G > T/A and CR0-24. However, it was observed that the polymorphism of TACR1, which encodes the neurokinin 1 receptor, might be a potential genetic risk factor for the development of delayed phase CINV.
