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Trial record 1 of 1 for:    NCT00072462
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Adjuvant Tamoxifen Compared With Anastrozole in Treating Postmenopausal Women With Ductal Carcinoma In Situ (IBIS-II DCIS)

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ClinicalTrials.gov Identifier: NCT00072462
Recruitment Status : Completed
First Posted : November 6, 2003
Last Update Posted : October 6, 2021
Cancer Research UK
Information provided by (Responsible Party):
Queen Mary University of London

Brief Summary:

RATIONALE: Estrogen can stimulate the growth of breast cancer cells. Hormone therapy using either tamoxifen or anastrozole may fight breast cancer by blocking the use of estrogen. It is not yet known whether tamoxifen is more effective than anastrozole in preventing breast cancer after surgery for ductal carcinoma in situ.

PURPOSE: This randomized phase III trial is studying how well adjuvant tamoxifen works compared to anastrozole in treating postmenopausal women who have undergone surgery to remove ductal carcinoma in situ.

Condition or disease Intervention/treatment Phase
Breast Cancer Drug: tamoxifen citrate Drug: Anastrozole Phase 3

Detailed Description:



  • Compare the efficacy of adjuvant tamoxifen vs anastrozole, in terms of local control and prevention of contralateral disease, in postmenopausal women with locally excised ductal carcinoma in situ.
  • Compare side effect profiles of these drugs in these patients.


  • Compare the efficacy of these drugs, according to the receptor status of the primary or recurrent cancer in these patients.
  • Compare the rate of breast cancer recurrence and growth of new contralateral tumors after cessation of treatment with these drugs in these patients.
  • Compare breast cancer mortality in patients treated with these drugs.
  • Compare the effect of these drugs on other cancers, cardiovascular disease, fracture rates, and non-breast cancer deaths in these patients.
  • Compare the tolerability and acceptability of side effects experienced by patients treated with these drugs.

OUTLINE: This is a randomized, double-blind, multicentre study. Patients are stratified according to participating centre. Patients are randomized to 1 of 2 treatment arms.

  • Arm I: Patients receive oral tamoxifen and oral placebo once daily.
  • Arm II: Patients receive oral anastrozole and oral placebo once daily. In both arms, treatment continues for 5 years in the absence of disease recurrence or unacceptable toxicity.

Patients are followed annually for 5 years and a further 5 years (minimum) off treatment.

Peer Reviewed and Funded by Cancer Research UK. Sponsored by Queen Mary University of London

ACTUAL ACCRUAL: A total of 2,980 patients were accrued for this study over 9 years.

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Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 2980 participants
Allocation: Randomized
Intervention Model: Single Group Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary Purpose: Treatment
Official Title: International Breast Cancer Intervention Study II (IBIS-II) (DCIS)
Study Start Date : September 2003
Actual Primary Completion Date : December 2015
Actual Study Completion Date : May 31, 2021

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Breast Cancer

Arm Intervention/treatment
Active Comparator: Anastrozole Drug: Anastrozole
Anastrozole 1mg + Tamoxifen placebo
Other Name: Arimidex

Active Comparator: Tamoxifen Drug: tamoxifen citrate
Tamoxifen 20mg + Anastrozole placebo
Other Name: Nolvadex

Primary Outcome Measures :
  1. Development of histologically confirmed breast cancer, both invasive and non-invasive with median follow-up at 5 years [ Time Frame: 2 years ]

Secondary Outcome Measures :
  1. To examine the effect of tamoxifen vs anastrozole on breast cancer mortality [ Time Frame: 7 years ]

Information from the National Library of Medicine

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Ages Eligible for Study:   40 Years to 70 Years   (Adult, Older Adult)
Sexes Eligible for Study:   Female
Accepts Healthy Volunteers:   No


  • Diagnosis of ductal carcinoma in situ within the past 6 months

    • Locally excised with tumor-free margins at least 1 mm
  • Hormone receptor status:

    • Estrogen or progesterone receptor positive

      • Equal to or greater than 5% positive cells



  • 40 to 70


  • Female

Menopausal status

  • Postmenopausal, defined as meeting at least 1 of the following criteria:

    • Over age 60
    • Prior bilateral oophorectomy
    • Age 60 or under with a uterus AND amenorrhea for at least the past 12 months
    • Age 60 or under without a uterus AND follicle-stimulating hormone greater than 20 IU/L

Performance status

  • Not specified

Life expectancy

  • At least 10 years


  • Not specified


  • Not specified


  • Not specified


  • No prior deep vein thrombosis
  • No prior transient ischemic attack
  • No prior cerebrovascular accident


  • No prior pulmonary embolism


  • No unexplained postmenopausal bleeding
  • No other cancer within the past 5 years except nonmelanoma skin cancer or carcinoma in situ of the cervix
  • No other concurrent medical condition that would preclude study therapy, place the patient at unusual risk, or confound study results
  • No evidence of osteoporosis
  • Fragility fractures within the spine allowed if T-score level is greater than -4 and consist of no more than 2 fractures
  • Psychologically and physically suitable for 5 years of study therapy


Biologic therapy

  • Not specified


  • Not specified

Endocrine therapy

  • No prior or concurrent tamoxifen use lasting more than 6 months unless treatment was completed more than 5 years ago. Women in IBIS-I can join if off trial therapy for at least 5 years.
  • No prior or concurrent raloxifene use lasting more than 6 months unless treatment was completed more than 5 years ago.
  • No other prior or concurrent selective estrogen-receptor modulator use lasting more than 6 months unless treatment was completed more than 5 years ago
  • No concurrent systemic estrogen-based hormone replacement therapy, including vaginal estrogen preparations


  • Not specified


  • See Disease Characteristics
  • No prior mastectomy
  • No planned prophylactic mastectomy


  • At least 3 months since prior unapproved or experimental agents
  • No concurrent anticoagulants

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 ClinicalTrials.gov identifier (NCT number): NCT00072462

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Sponsors and Collaborators
Queen Mary University of London
Cancer Research UK
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Study Chair: Jack Cuzick, PhD Queen Mary University of London
Study Chair: Anthony Howell University of Manchester
Additional Information:
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Responsible Party: Queen Mary University of London
ClinicalTrials.gov Identifier: NCT00072462    
Other Study ID Numbers: ISRCTN37546358
First Posted: November 6, 2003    Key Record Dates
Last Update Posted: October 6, 2021
Last Verified: September 2021
Keywords provided by Queen Mary University of London:
ductal breast carcinoma in situ
breast cancer in situ
Additional relevant MeSH terms:
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Breast Neoplasms
Carcinoma in Situ
Neoplasms by Site
Breast Diseases
Skin Diseases
Neoplasms, Glandular and Epithelial
Neoplasms by Histologic Type
Molecular Mechanisms of Pharmacological Action
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
Aromatase Inhibitors
Steroid Synthesis Inhibitors
Enzyme Inhibitors