Abstract:

Objective To investigate the correlation between CYP2D6，and SULT1A1 gene polymor⁃ phisms and treatment effect of tamoxifen（TAM）in patients with breast cancer. Methods From January 2018 to January 2019，203 patients treated with TAM were included in the study. The genotype of CYP2D6（100C > t） and SULT1A1 638（G > A）was detected，and the correlation between genotypes，clinicopathological parameters， and the prognosis was analyzed. Kaplan Meier method was used for survival analysis，and log rank test was used to test whether there was survival difference among patients. Results Among 203 cases，44 cases（21.67%），117 cases （57.64%）and 42 cases（20.69%）were CYP2D6（100C > t）CC，CT and TT respectively. Sult1A1 638（G > A） was all GG type，and no GA or AA type was found. The 2⁃year OS rate of patients with CC and CT was higher than that of patients with TT（P = 0.001）. The OS of CC and CT patients was significantly longer than that of TT patients （P = 0.001）. Conclusion The OS of TT patients after TAM treatment is significantly lower than that of CC and CT patients. No allele mutation is found in SULT1A1 638（G > A）.

Key words:

breast cancer, tamoxifen, CYP2D6, SULT1A1, gene polymorphism