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NCT00003016 · CITED IN SOURCE DOCUMENTS

Prolonged Tamoxifen Compared With Shorter Tamoxifen in Treating Patients Who Have Breast Cancer

An NCI or FDA source cites this study. A citation does not establish that it applies to an individual diagnosis.

Phase
PHASE3
Status at capture
UNKNOWN
Registry last update
2009-02-09

RATIONALE: Estrogen can stimulate the growth of breast cancer cells. Hormone therapy using tamoxifen may fight breast cancer by reducing the production of estrogen. It is not yet known if prolonged tamoxifen is more effective than shorter tamoxifen therapy following curative treatment for breast cancer. PURPOSE: This randomized phase III trial is studying giving tamoxifen over a prolonged period of time to see how well it works compared to giving tamoxifen over a shorter period of time in treating patients who have had a breast tumor removed.

Open the original ClinicalTrials.gov record → · Download preserved record

What did the study report?

Outcomes, safety and baseline populations are separate source sections. Quality-of-life measures appear under their original outcome titles.

No posted result sections were captured. Registered plans do not establish that a treatment works.

Who could take part
eligibility Criteria
DISEASE CHARACTERISTICS: * Curatively treated carcinoma of the breast * Currently taking adjuvant tamoxifen * Must be substantial uncertainty as to whether or not to continue tamoxifen (i.e., no clear indication or definite contraindication to further treatment with tamoxifen) PATIENT CHARACTERISTICS: Age: * Any age Performance status: * Not specified Life expectancy: * Not specified Hematopoietic: * Not specified Hepatic: * Not specified Renal: * Not specified Other: * Not pregnant or nursing * No contraindications to receiving tamoxifen * No other serious medical problems PRIOR CONCURRENT THERAPY: Biologic therapy: * Prior biologic therapy allowed Chemotherapy: * Prior chemotherapy allowed Endocrine therapy: * See Disease Characteristics Radiotherapy: * Prior radiotherapy allowed Surgery: * Prior surgery allowed
healthy Volunteers
false
sex
ALL
std Ages
  1. CHILD
  2. ADULT
  3. OLDER_ADULT
Treatment arms and interventions
interventions
  1. name
    tamoxifen citrate
    type
    DRUG
  2. name
    adjuvant therapy
    type
    PROCEDURE
Study design
allocation
RANDOMIZED
primary Purpose
TREATMENT
Enrollment
count
20000
type
ESTIMATED
Registered outcome plans (not posted results)
primary Outcomes
  1. measure
    Overall survival (i.e., all-cause mortality)
secondary Outcomes
  1. measure
    Specific-cause mortality
  2. measure
    Incidence of second primary tumors
Full study description
brief Summary
RATIONALE: Estrogen can stimulate the growth of breast cancer cells. Hormone therapy using tamoxifen may fight breast cancer by reducing the production of estrogen. It is not yet known if prolonged tamoxifen is more effective than shorter tamoxifen therapy following curative treatment for breast cancer. PURPOSE: This randomized phase III trial is studying giving tamoxifen over a prolonged period of time to see how well it works compared to giving tamoxifen over a shorter period of time in treating patients who have had a breast tumor removed.
detailed Description
OBJECTIVES: * Assess the balance of risks and benefits in prolonging the duration of adjuvant tamoxifen by at least 5 years in patients with curatively treated breast cancer who have already had about 5 years of adjuvant tamoxifen. OUTLINE: This is a randomized study. After about 5 years of adjuvant tamoxifen, recurrence-free patients are randomized to stop tamoxifen treatment immediately or to continue tamoxifen treatment for at least 5 more years. Patients are followed annually. PROJECTED ACCRUAL: Approximately 20,000 patients will be accrued for this study.
Source references
Source notices and limitations
    Discovery and provenance
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      occurrences
      1. context exact
        n, 7.9%; <em>P</em> = .01) was observed.</li></ul></div></li><li>Long-term follow-up of the Adjuvant Tamoxifen Longer Against Shorter (<a href="/clinicaltrials/NCT00003016">ATLAS</a> [NCT00003016]) trial demonstrated that 10 years of tamoxifen therapy was superior to 5 years of tamoxifen therapy. Between 1996 and 2005, 12,894 wom
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      2. context exact
        1) was observed.</li></ul></div></li><li>Long-term follow-up of the Adjuvant Tamoxifen Longer Against Shorter (<a href="/clinicaltrials/NCT00003016">ATLAS</a> [NCT00003016]) trial demonstrated that 10 years of tamoxifen therapy was superior to 5 years of tamoxifen therapy. Between 1996 and 2005, 12,894 women with early breast can
        end
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        start
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      3. context exact
        ="-1"> <strong>Tamoxifen</strong> </p> <div class="pdq-content-list"><ol id="_3504"><li>Long-term follow-up of the <a href="/clinicaltrials/NCT00003016">ATLAS</a> trial (NCT00003016) included toxicity data. Compared with 5 years, 10 years of tamoxifen therapy increased the risk of the following:[<a href="#cit/
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      4. context exact
        en</strong> </p> <div class="pdq-content-list"><ol id="_3504"><li>Long-term follow-up of the <a href="/clinicaltrials/NCT00003016">ATLAS</a> trial (NCT00003016) included toxicity data. Compared with 5 years, 10 years of tamoxifen therapy increased the risk of the following:[<a href="#cit/section_7.16">16</a>]<div clas
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      source string sha256
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      source title
      Breast Cancer Treatment (PDQ®)–Health Professional Version
      source update dates
      1. context
        Updated: April 25, 2025
        datetime
        2025-04-25T12:00:00Z
        display
        April 25, 2025

    Preserved source evidence · Not medical advice