NCT00966043

Prevalence of Genetic Polymorphisms in Genes Coding for Tamoxifen Metabolising Enzymes

Prevalence of Genetic Polymorphisms in Genes Coding for Tamoxifen Metabolising Enzymes, in Postmenopausal ER-positive Breast Cancer Patients According to Uterine and Biochemical Changes and Tolerability of Tamoxifen.

• Status: Completed
• Phase: —
• Study type: Observational
• Enrollment: 158 (actual)
• Sponsor: Vlaamse Vereniging voor Obstetrie en Gynaecologie · Academic / Other
• Sex: Female
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

CYPTAM-BRUT 3 is a prospective, multicentric study in Belgium within the CYPTAM study of the Leiden University Medical Center (NTR1509) including postmenopausal women receiving tamoxifen for estrogen-receptor positive breast cancer in the adjuvant setting. The primary endpoint is the difference in uterine changes between women with a normal versus low TAS after 3 months of tamoxifen use. Secondary endpoints are serum metabolite concentrations, serum follicle-stimulating hormone level, serum sex hormone-binding globulin level and menopausal symptoms. These patients are registered in the Leiden protocol with time to breast cancer event as primary endpoint.

Detailed description

We will study the impact of the 'tamoxifen activity score' - based on functional genetic polymorphisms for tamoxifen metabolism and the use of drugs that interfere with tamoxifen-against tamoxifen related endpoints like uterine changes and subjective menopausal symptoms. The prevalence of genetic polymorphisms in the CYP2D6 and other genes and differences in usage of drugs interacting with tamoxifen metabolism will be compared between women with and those without endometrial thickening on one hand and between women with and those without hot flashes on the other hand. Tamoxifen use in adjuvant setting. * "Tamoxifen activity score" (23): The endpoints will be correlated with a predefined 'tamoxifen activity score' which is based on the presence of single nucleotide polymorphisms (SNP) in relevant genes combined with the effect of well known drugs that interfere with the metabolism of tamoxifen. The 'tamoxifen activity score' has been associated with tamoxifen compliance by a group in the US (23). The score will be adapted to the Belgian situation based on the prevalence of these SNPs in a Belgian population of volunteers for blood donation and consecutive breast cancer patients. * The study setting are postmenopausal women with an early ER- positive breast cancer and not previously treated with an endocrine agent or hormone replacement therapy, with an intact uterus and clearly measurable thin endometrium/uterus. N =250

Conditions

• Breast Neoplasms

Timeline

• Start date: 2009-06-01
• Primary completion: 2011-07-01
• Completion: 2011-07-01
• First posted: 2009-08-26
• Last updated: 2015-10-28

Locations

11 sites across 1 country: Belgium