Tamoxifen in Treating Women With Breast Cancer

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00003678
Recruitment Status : Unknown
Verified March 2007 by National Cancer Institute (NCI).
Recruitment status was:  Active, not recruiting
First Posted : January 27, 2003
Last Update Posted : December 19, 2013
Information provided by:
National Cancer Institute (NCI)

Brief Summary:

RATIONALE: Estrogen can stimulate the growth of breast cancer cells. Hormone therapy using tamoxifen may fight breast cancer by blocking the uptake of estrogen by the tumor cells.

PURPOSE: Randomized phase III trial to compare the effectiveness of at least 2 years of tamoxifen with that of 5 additional years of tamoxifen in treating women who have breast cancer that has been surgically removed.

Condition or disease Intervention/treatment Phase
Breast Cancer Drug: tamoxifen citrate Procedure: adjuvant therapy Phase 3

Detailed Description:


  • Compare the disease-free and overall survival of women with early breast cancer who are randomized to discontinue adjuvant tamoxifen vs those randomized to continue for at least 5 additional years.

OUTLINE: This is a randomized study. Patients are stratified for analysis according to duration of tamoxifen given before randomization (2-3 years vs 4-5 years vs 6-7 years vs 8-9 years vs 10 years and over), age (less than 49 vs over 50), and important prognostic factors, including tumor type and grade and nodal and estrogen receptor status. Patients are randomized to 1 of 2 treatment arms.

  • Arm I: Patients discontinue tamoxifen after at least 2 years of prior treatment.
  • Arm II: Patients continue treatment with tamoxifen for at least 5 additional years in the absence of unacceptable toxicity or disease progression.

Patients are followed annually.

Peer Reviewed and Funded or Endorsed by Cancer Research UK

PROJECTED ACCRUAL: A total of 8,000-20,000 patients will be accrued for this study.

Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 20000 participants
Allocation: Randomized
Primary Purpose: Treatment
Official Title: A Large, Uniquely Simple, Randomised Study to Assess Much More Reliably the Balance of Benefits and Risks of Prolonging Adjuvant Tamoxifen Treatment in Early Breast Cancer
Study Start Date : May 1991

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Breast Cancer
U.S. FDA Resources

Primary Outcome Measures :
  1. All-cause mortality

Secondary Outcome Measures :
  1. Disease recurrence
  2. Death due to breast cancer, other primary tumors, or cardiovascular causes

Information from the National Library of Medicine

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Ages Eligible for Study:   Child, Adult, Senior
Sexes Eligible for Study:   Female
Accepts Healthy Volunteers:   No


  • Histologically confirmed breast carcinoma that has been completely excised

    • Clinically relapse free
  • Must have completed at least two years of adjuvant therapy with tamoxifen for early breast cancer AND have no clear indication for or against receiving further tamoxifen
  • No significant endometrial hyperplasia
  • No patients with negligibly low risk of breast cancer death
  • Hormone receptor status:

    • Any status allowed



  • Not specified


  • Female

Menopausal status:

  • Any status allowed

Performance status:

  • Not specified

Life expectancy:

  • Not specified


  • Not specified


  • Not specified


  • Not specified


  • No other life threatening disease
  • No retinopathy
  • No psychiatric disorder or other condition that would preclude study compliance
  • No serious toxicity (e.g., depression) thought to be due to tamoxifen
  • Not pregnant or nursing
  • Fertile patients must use effective contraception


Biologic therapy:

  • Not specified


  • Not specified

Endocrine therapy:

  • See Disease Characteristics


  • Not specified


  • See Disease Characteristics


  • Any primary treatment allowed

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT00003678

United Kingdom
Cancer Research UK Clinical Trials Unit - Birmingham
Birmingham, England, United Kingdom, B15 2TT
Sponsors and Collaborators
University Hospital Birmingham
Study Chair: Daniel Rea, MD University Hospital Birmingham

Publications: Identifier: NCT00003678     History of Changes
Other Study ID Numbers: CDR0000066779
First Posted: January 27, 2003    Key Record Dates
Last Update Posted: December 19, 2013
Last Verified: March 2007

Keywords provided by National Cancer Institute (NCI):
stage I breast cancer
stage II breast cancer

Additional relevant MeSH terms:
Breast Neoplasms
Neoplasms by Site
Breast Diseases
Skin Diseases
Estrogen Antagonists
Hormone Antagonists
Hormones, Hormone Substitutes, and Hormone Antagonists
Physiological Effects of Drugs
Antineoplastic Agents, Hormonal
Antineoplastic Agents
Selective Estrogen Receptor Modulators
Estrogen Receptor Modulators
Bone Density Conservation Agents