Clinical trial · Interventional
Tamoxifen in Treating Women With Breast Cancer
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
NCT00003678CI-TRIAL-00013126unknownPhase 3ClinicalTrials.gov clinicaltrialsProvenance
- Source
- ClinicalTrials.gov
- Retrieved
- Sep 8, 2026
- Layer
- normalized (units and labels harmonized; values unchanged)
- Run
- ING-CLINICALTRIALS-20260908-000001
Summary
Brief summary (as posted)
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.
Conditions
Conditions (1)
Free-text conditions as registered, with the CancerIndex entity they were reconciled to and the match type.
| Condition (as posted) | Mapped entity | Match | Confidence |
|---|---|---|---|
| Breast Cancer | Malignant Breast Neoplasm | CURATED_EXACT | 0.92 |
Interventions
Interventions (2)
| Intervention | Type | Mapped drug | Match |
|---|---|---|---|
| adjuvant therapy | Procedure | — | UNRESOLVED |
| tamoxifen citrate | Drug | Tamoxifen | ALIAS |
Design
Arms and outcomes
Arms (0)
[]Primary outcomes (1)
- measure
- All-cause mortality
Secondary outcomes (2)
- measure
- Disease recurrence
- measure
- Death due to breast cancer, other primary tumors, or cardiovascular causes
Eligibility
Eligibility (as posted)
- Sex
- Female
Show eligibility criteria text
DISEASE CHARACTERISTICS: * 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 PATIENT CHARACTERISTICS: Age: * Not specified Sex: * Female Menopausal status: * Any status allowed Performance status: * Not specified Life expectancy: * Not specified Hematopoietic: * Not specified Hepatic: * Not specified Renal: * Not specified Other: * 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 PRIOR CONCURRENT THERAPY: Biologic therapy: * Not specified Chemotherapy: * Not specified Endocrine therapy: * See Disease Characteristics Radiotherapy: * Not specified Surgery: * See Disease Characteristics Other: * Any primary treatment allowed
References
Publications (7)
- BACKGROUNDGray R, Davies C, Perry P. Tamoxifen for early breast cancer: better late than never. Ann Oncol. 2000 May;11(5):505-7. doi: 10.1023/a:1008323116265. No abstract available. PMID 10907940
- BACKGROUNDRea D, Poole C, Gray R. Adjuvant tamoxifen: how long before we know how long? BMJ. 1998 May 16;316(7143):1518-9. doi: 10.1136/bmj.316.7143.1518. No abstract available. PMID 9582148
- BACKGROUNDEarl H, Gray R, Kerr D, Lee M. The optimal duration of adjuvant tamoxifen treatment for breast cancer remains uncertain: randomize into aTTom. Clin Oncol (R Coll Radiol). 1997;9(3):141-3. doi: 10.1016/s0936-6555(97)80067-2. No abstract available. PMID 9269542
- BACKGROUNDEarl H, Baker P, Kerr D, Lee M, Gray R, Baum M. Adjuvant treatment with tamoxifen. Recruitment into studies assessing optimum duration of treatment must continue. BMJ. 1996 Apr 20;312(7037):1036-7. doi: 10.1136/bmj.312.7037.1036b. No abstract available. PMID 8616358
- BACKGROUNDGray R. Tamoxifen: how boldly to go where no women have gone before. J Natl Cancer Inst. 1993 Sep 1;85(17):1358-60. doi: 10.1093/jnci/85.17.1358. No abstract available. PMID 8350355
- DERIVEDPoterala JE, Wisinski KB. Abbreviated endocrine therapy duration for low estrogen receptor-positive breast cancer: The counter to extended endocrine therapy. Cancer. 2022 May 1;128(9):1724-1726. doi: 10.1002/cncr.34158. Epub 2022 Feb 25. No abstract available. PMID 35213039
- DERIVEDBartlett JMS, Sgroi DC, Treuner K, Zhang Y, Ahmed I, Piper T, Salunga R, Brachtel EF, Pirrie SJ, Schnabel CA, Rea DW. Breast Cancer Index and prediction of benefit from extended endocrine therapy in breast cancer patients treated in the Adjuvant Tamoxifen-To Offer More? (aTTom) trial. Ann Oncol. 2019 Nov 1;30(11):1776-1783. doi: 10.1093/annonc/mdz289.