BACKGROUND: Previous studies evaluating the effect of cytochrome P450 2D6 (CYP2D6) polymorphisms on outcomes of adjuvant tamoxifen therapy have been conflicting due to differences in study design, concomitant medications that alter CYP2D6 metabolism, and tamoxifen adherence. METHODS: The authors performed CYP2D6 genotyping from whole blood and fresh frozen tumor samples (n 106) in patients at The University of Texas MD Anderson Cancer Center who were receiving, or had received, tamoxifen as adjuvant therapy for early breast cancer (EBC), using the AmpliChip CYP450 Test. Each patient's medical history was assessed for drugs that affected CYP2D6. Fifty-five patients who had experienced breast cancer recurrence were matched (by date of diagnosis, menopausal status, clinical stage [TNM Staging System], and race) to patients without recurrence. RESULTS: Unadjusted for other patient characteristics, the odds ratio for disease recurrence associated with CYP2D6 functional status was 1.0 (95% confidence interval, 0.35-2.85). After adjustment for stage, CYP2D6 inhibitors (moderate or strong vs none), and follow-up time, no significant association was found between CYP2D6 genotype and breast cancer recurrence in patients who were treated with adjuvant tamoxifen for EBC. CONCLUSIONS: This case-control study demonstrated no significant effect of CYP2D6 genotype on risk of recurrence in breast cancer patients who received adjuvant tamoxifen therapy.
BACKGROUND: Previous studies evaluating the effect of cytochrome P450 2D6 (CYP2D6) polymorphisms on outcomes of adjuvant tamoxifen therapy have been conflicting due to differences in study design, concomitant medications that alter CYP2D6 metabolism, and tamoxifen adherence. METHODS: The authors performed CYP2D6 genotyping from whole blood and fresh frozen tumor samples (n 106) in patients at The University of Texas MD Anderson Cancer Center who were receiving, or had received, tamoxifen as adjuvant therapy for early breast cancer (EBC), using the AmpliChip CYP450 Test. Each patient's medical history was assessed for drugs that affected CYP2D6. Fifty-five patients who had experienced breast cancer recurrence were matched (by date of diagnosis, menopausal status, clinical stage [TNM Staging System], and race) to patients without recurrence. RESULTS: Unadjusted for other patient characteristics, the odds ratio for disease recurrence associated with CYP2D6 functional status was 1.0 (95% confidence interval, 0.35-2.85). After adjustment for stage, CYP2D6 inhibitors (moderate or strong vs none), and follow-up time, no significant association was found between CYP2D6 genotype and breast cancer recurrence in patients who were treated with adjuvant tamoxifen for EBC. CONCLUSIONS: This case-control study demonstrated no significant effect of CYP2D6 genotype on risk of recurrence in breast cancerpatients who received adjuvant tamoxifen therapy.
Authors: Mariella De Ameida Melo; Rodrigo José De Vasconcelos-Valença; Fidelis Manes Neto; Rafael Soares Borges; Danylo Rafhael Costa-Silva; Maria Da Conceição Barros-Oliveira; Umbelina Soares Borges; Airlane Pereira Alencar; Vladimir Costa Silva; Benedito Borges Da Silva Journal: Biomed Rep Date: 2016-10-04
Authors: Sudharsan Periyasamy-Thandavan; Suchreet Takhar; Adam Singer; Michael Robert Dohn; William Hutch Jackson; April Eve Welborn; Derek LeRoith; Mario Marrero; Muthusamy Thangaraju; Shuang Huang; Patricia Veronica Schoenlein Journal: Breast Cancer Res Date: 2012-03-19 Impact factor: 6.466
Authors: Saskia Preissner; Mathias Dunkel; Michael F Hoffmann; Sarah C Preissner; Nikolai Genov; Wen Wei Rong; Robert Preissner; Karlheinz Seeger Journal: PLoS One Date: 2012-12-07 Impact factor: 3.240
Authors: Thomas P Ahern; Richard F MacLehose; Laura Haines; Deirdre P Cronin-Fenton; Per Damkier; Lindsay J Collin; Timothy L Lash Journal: BMJ Evid Based Med Date: 2020-03-27