Adjuvant Tamoxifen Compared With Anastrozole in Treating Postmenopausal Women With Ductal Carcinoma In Situ

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

RATIONALE: Estrogen can stimulate the growth of breast cancer cells. Hormone therapy using either tamoxifen or anastrozole may fight breast cancer by blocking the uptake 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: Randomizedphase III trial to compare the effectiveness of adjuvant tamoxifen with that of anastrozole in treating postmenopausal women who have undergone surgery to remove ductal carcinoma in situ. Condition:- intraductal breast carcinoma- breast cancer in situ Study Type: InterventionalStudy Design: Treatment Official Title: Phase III Randomized Study of Adjuvant Tamoxifen Versus Anastrozole in Postmenopausal Women With Ductal Carcinoma In SituFurther Study Details: OBJECTIVES: PrimaryCompare 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. SecondaryCompare 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, multicenter study. Patients are stratified according to participating center. 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.PROJECTED ACCRUAL: A total of 4,000 patients will be accrued for this study within 4 years. Eligibility Ages Eligible for Study: 40 Years – 70 Years, Genders Eligible for Study: Both Criteria DISEASE CHARACTERISTICS: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 Greater than 5% positive cells PATIENT CHARACTERISTICS: Age40 to 70 SexFemale Menopausal statusPostmenopausal, 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 statusNot specified Life expectancyAt least 10 years HematopoieticNot specified HepaticNot specified RenalNot specified CardiovascularNo prior deep vein thrombosis No prior transient ischemic attack No prior cerebrovascular accident PulmonaryNo prior pulmonary embolism OtherNo 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 PRIOR CONCURRENT THERAPY: Biologic therapyNot specified ChemotherapyNot specified Endocrine therapyNo prior or concurrent tamoxifen use lasting more than 3 months No prior or concurrent raloxifene use lasting more than 3 months No other prior or concurrent selective estrogen-receptor modulator use lasting more than 3 months No concurrent systemic estrogen-based hormone replacement therapy, including vaginal estrogen preparations RadiotherapyNot specified SurgerySee Disease Characteristics No prior mastectomy No planned prophylactic mastectomy OtherNo prior participation in the International Breast Cancer Intervention Study At least 3 months since prior unapproved or experimental agents No concurrent anticoagulants [1] Cancer Research UK