BACKGROUND/AIM: The role of single nucleotide polymorphisms (SNPs) in the frequency and intensity of chemotherapy-induced nausea and vomiting (CINV) in women with breast cancer (BC) is unclear. The primary purpose of this study was to compare/evaluate the effect of SNP-guided antiemetic treatment versus standard CINV treatment.

PATIENTS AND METHODS: A randomised, factorial, phase II multicentre study design was used. Women planned for neoadjuvant or adjuvant chemotherapy with epirubicin, cyclophosphamide and fluorouracil (FEC /EC, with or without fluorouracil) for BC were randomised to SNP-guided antiemetic treatment (based on the results of SNP analyses) versus standard CINV treatment. Blood samples were taken before the treatment was initiated. Patient-reported data on CINV (during 10 days from onset of cancer treatment) and health-related quality of life (HRQoL), were collected before and after the first cancer treatment.

RESULTS: A total of 188 women were included. Overall, nausea was reported by 86% (n=129) of the patients during the ten-day period from the start of cancer treatment. The SNP genotype studied varied. In FAS-CD95, the genotypes AG and GG were overrepresented; in RB1-LPAR6, GG was overrepresented, and in CCL2, both AA and GG were overrepresented. We found no statistically significant difference in CINV between SNP-guided antiemetic treatment versus standard CINV treatment.

CONCLUSION: SNP-guided antiemetic treatment could be as effective as standard treatment. SNP-guided antiemetic treatment of CINV is possibly useful in detecting patients with a higher or lower risk for CINV and thus may help in avoiding over-treatment with toxic components. CINV negatively affects the HRQL.