No association between CYP2D6*10 genotype and survival of node-negative Japanese breast cancer patients receiving adjuvant tamoxifen treatment.
OBJECTIVE
The CYP2D6 enzyme plays a major role in converting tamoxifen to its active metabolites. We investigated whether there is an association between the CYP2D6*10 allele and clinical outcome in node-negative Japanese breast cancer patients.


METHODS
CYP2D6 genotyping was performed in 154 node-negative breast cancer patients who had received adjuvant tamoxifen treatment alone. The CYP2D6 genotypes were determined using the TaqMan Allelic Discrimination Assay.


RESULTS
Eighteen percent (28 of 154) of the patients carried the CYP2D6*10/*10 genotype, 40% the CYP2D6 wild-type (wt)/*10 genotype and 42% the CYP2D6 wt/wt genotype. There were no discernible correlations between clinicopathologic parameters and the CYP2D6*10 genotype. Next, we determined whether there was a correlation between the CYP2D6*10 genotype and survival and found that the clinical outcome for patients carrying the CYP2D6*10/*10 genotype was similar to those with other genotypes.


CONCLUSIONS
Our results suggest that the CYP2D6*10 genotype is unlikely to have any clinical significance for prognosis of node-negative Japanese breast cancer patients receiving adjuvant tamoxifen alone.
Toyama
Tatsuya
T
Department of Oncology, Immunology and Surgery, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan. t.toyama@med.nagoya-cu.ac.jp
Yamashita
Hiroko
H
Sugiura
Hiroshi
H
Kondo
Naoto
N
Iwase
Hirotaka
H
Fujii
Yoshitaka
Y
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018931:Antineoplastic Agents, Hormonal / Q000627:therapeutic use*; D044466:Asian People / Q000235:genetics; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000235:genetics; D017024:Chemotherapy, Adjuvant; D019389:Cytochrome P-450 CYP2D6 / Q000235:genetics*; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D005838:Genotype; D006801:Humans; D007150:Immunohistochemistry; D008198:Lymph Nodes / Q000473:pathology; D008875:Middle Aged; D011110:Polymorphism, Genetic; D013629:Tamoxifen / Q000627:therapeutic use*
D018931:Antineoplastic Agents, Hormonal; D013629:Tamoxifen; D019389:Cytochrome P-450 CYP2D6