Prevalence of Genetic Polymorphisms in Genes Coding for Tamoxifen Metabolising Enzymes (CYPTAMBRUT-3)

This study has been completed.
Information provided by (Responsible Party):
Vlaamse Vereniging voor Obstetrie en Gynaecologie Identifier:
First received: August 24, 2009
Last updated: October 27, 2015
Last verified: October 2015
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.

Condition Phase
Breast Neoplasms
Phase 3

Study Type: Observational
Study Design: Observational Model: Cohort
Time Perspective: Prospective
Official Title: 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.

Resource links provided by NLM:

Further study details as provided by Vlaamse Vereniging voor Obstetrie en Gynaecologie:

Primary Outcome Measures:
  • change in endometrial thickness or uterine volume [ Time Frame: 3-6 months ] [ Designated as safety issue: No ]

Secondary Outcome Measures:
  • Tolerability of tamoxifen-HRQoL questionnaire [ Time Frame: 3-6 months ] [ Designated as safety issue: No ]
  • Vaginal bleeding [ Time Frame: 3-6 months ] [ Designated as safety issue: No ]
  • Biochemical changes [ Time Frame: 3-6 months ] [ Designated as safety issue: No ]

Enrollment: 158
Study Start Date: June 2009
Study Completion Date: July 2011
Primary Completion Date: July 2011 (Final data collection date for primary outcome measure)
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

Ages Eligible for Study:   18 Years and older
Genders Eligible for Study:   Female
Accepts Healthy Volunteers:   No
Sampling Method:   Non-Probability Sample
Study Population
Postmenopausal female breast cancer patients starting adjuvant tamoxifen therapy.

Inclusion Criteria:

  • Female > 18 years of age
  • Written and voluntary informed consent understood signed and dated
  • Histologically or cytologically confirmed measurable invasive adenocarcinoma of the breast, amenable to curative therapy.
  • Patients must be postmenopausal as defined by criteria in appendix 1.
  • Breast cancer should be considered as oestrogen receptor positive by the clinician using immunohistochemistry readings as is standard procedure for local pathologist
  • Prior endocrine tamoxifen therapy is not allowed
  • Patients are not previously treated with an endocrine agent or hormone replacement therapy needs being stopped for at least 6 months.
  • Prior chemotherapy and radiotherapy is allowed
  • Adequate renal and liver function Serum creatinine and serum bilirubin ≤ 1.5 X ULN Serum ALT and AST ≤ 2.5 X ULN (or ≤ 5 in case of liver metastases)
  • Serum calcium should be ≤ 11,6 mg/dl
  • ECOG performance status 0,1,2 (appendix 2)

Exclusion Criteria:

  • Male
  • Life threatening disease requiring a quick response (eg, extensive hepatic or pulmonary involvement)
  • Use of any endocrine treatment or recent/current use of hormone replacement therapy.
  • Contra indication for tamoxifen: history of DVT/vaginal bleeding of unknown origin
  • Dementia
  • History of other malignancy that may interfere with at least 6 months of tamoxifen therapy
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT00966043

AZ St-Maarten
Duffel, Antwerpen, Belgium, 2570
AZ St-Nikolaas
St-Niklaas, Antwerpen, Belgium, 9100
Ziekenhuizen Oost-Limburg Camus St-Jan
Genk, Limburg, Belgium, 3600
AZ St-Blasius
Dendermonde, Ookst-Vlaanderen, Belgium, 9200
Gent, Oost-Vlaanderen, Belgium, 9000
Gent, Oost-Vlaanderen, Belgium, 9000
Leuven, Vlaams-Brabant, Belgium, 3000
Heilig-Hart Ziekenhuis
Roeselare, West-Vlaanderen, Belgium, 8800
Institut Bordet
Brussel, Belgium, 1000
Brussel, Belgium, 1200
Brussel, Belgium, 1090
Sponsors and Collaborators
Vlaamse Vereniging voor Obstetrie en Gynaecologie
Principal Investigator: Patrick Neven UZ Leuven
  More Information

No publications provided

Responsible Party: Vlaamse Vereniging voor Obstetrie en Gynaecologie Identifier: NCT00966043     History of Changes
Other Study ID Numbers: Eudract 2009-010059-28., S 51521
Study First Received: August 24, 2009
Last Updated: October 27, 2015
Health Authority: Belgium: Federal Agency for Medicinal Products and Health Products

Additional relevant MeSH terms:
Breast Neoplasms
Breast Diseases
Neoplasms by Site
Skin Diseases processed this record on November 30, 2015