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

Reliable Assessment of the Efficacy and Safety of Prolonging the Use of Adjuvant Tamoxifen: A Large, Simple, Randomised Study

Status

UNKNOWN

Phases

Phase 3

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT00003016

Enrollment

20000

Registered

2003-01-27

Start date

1995-10-31

Completion date

Unknown

Last updated

2009-02-09

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Breast Cancer

Keywords

stage I breast cancer, stage II breast cancer, stage IIIA breast cancer, stage IIIB breast cancer, stage IIIC breast cancer

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.

Interventions

DRUGtamoxifen citrate

PROCEDUREadjuvant therapy

Study design

Allocation

RANDOMIZED

Primary purpose

TREATMENT

Eligibility

Sex/Gender

ALL

Healthy volunteers

Inclusion 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

Design outcomes

Primary

Measure	Time frame
Overall survival (i.e., all-cause mortality)	—

Secondary

Measure	Time frame
Specific-cause mortality	—
Incidence of second primary tumors	—

Countries

United Kingdom

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026