Table 4.
Prevalence of CYP2D6*2, CYP2D6*4, CYP2D6*10, and CYP3A5*3 in Thai breast cancer patients undergoing TAM treatment (N=134)
| Genotype (phenotype) | Prevalence (%) |
|---|---|
| CYP2D6 | |
| CYP2D6*1/*1 (EM) | 13 (9.7) |
| CYP2D6*1/*2 (EM) | 3 (2.2) |
| CYP2D6*2/*2 (EM) | 5 (3.7) |
| CYP2D6*4/*4 (PM) | 2 (1.5) |
| CYP2D6*1/*10 (EM) | 21 (15.7) |
| CYP2D6*2/*10 (EM) | 13 (9.7) |
| CYP2D6*4/*10 (IM) | 5 (3.7) |
| CYP2D6*10/*10 (IM) | 72 (53.7) |
| CYP3A5 | |
| CYP3A5*1/*1 (EM) | 18 (13.4) |
| CYP3A5*1/*3 (EM) | 64 (47.8) |
| CYP3A5*3/*3 (PM) | 52 (38.8) |
Abbreviations: TAM, tamoxifen; EM, extensive metabolizer; PM, poor metabolizer; IM, intermediate metabolizer.