Clinical trial NCT00003140 (phase 3, status: completed)
Conditions: breast cancer
ICD codes: C79.81, D24.1, D24.2, D24.9, D49.3, C44.501, D48.60
Drugs: letrozole
SMILES: N#CC1=CC=C(C=C1)C(N1C=NC=N1)C1=CC=C(C=C1)C#N
Eligibility criteria:

        DISEASE CHARACTERISTICS:

          -  Histologically or cytologically confirmed primary invasive breast carcinoma resected
             at time of original diagnosis

               -  No ductal carcinoma in situ

          -  Axillary lymph node negative, positive, or unknown

          -  No evidence of metastases

          -  No localized or distant breast cancer recurrence

          -  Not registered on protocol NCCTG-893052, any other IBCSG protocol, or protocol
             SWOG-S9623

          -  Hormone receptor status:

               -  Estrogen or progesterone receptor positive as defined by tumor receptor content
                  at least 10 fmol/mg protein or receptor positive by ERICA or PgRICA

               -  Unknown status allowed if effort to determine status has been made by
                  immunocytochemistry

          -  No contralateral breast cancer

        PATIENT CHARACTERISTICS:

        Age:

          -  Postmenopausal

        Sex:

          -  Female

        Menopausal status:

          -  Postmenopausal defined by one of the following:

               -  Age 50 or over at start of adjuvant tamoxifen

               -  Under age 50 and considered postmenopausal by treating physician at start of
                  adjuvant tamoxifen

               -  Under age 50 at start of adjuvant tamoxifen and had bilateral oophorectomy
                  (surgical or radiation)

               -  Under age 50 and premenopausal at start of adjuvant tamoxifen, but became
                  amenorrheic during tamoxifen and remained amenorrheic for at least 1 year

               -  Considered postmenopausal by physician with LH/FSH levels under the treatment
                  center's postmenopausal limits

        Performance status:

          -  ECOG 0-2

        Life expectancy:

          -  At least 5 years

        Hematopoietic:

          -  WBC ≥ 3,000/mm^3 OR

          -  Granulocyte count ≥ 1,500/mm^3

          -  Platelet count ≥ 100,000/mm^3

        Hepatic:

          -  AST and/or ALT < 2 times upper limit of normal (ULN) (unless imaging examinations have
             ruled out metastatic disease)

          -  Alkaline phosphatase < 2 times ULN (unless imaging examinations have ruled out
             metastatic disease)

        Renal:

          -  Not specified

        Other:

          -  No concurrent medical or psychiatric condition that would preclude study participation

          -  No other malignancy within the past 5 years except adequately treated superficial
             squamous cell or basal cell skin cancer or carcinoma in situ of the cervix

          -  Able to swallow study drug

          -  Adequate oral intake

        PRIOR CONCURRENT THERAPY:

        Biologic therapy:

          -  Not specified

        Chemotherapy:

          -  Prior adjuvant chemotherapy allowed

          -  No concurrent chemotherapy

        Endocrine therapy:

          -  Completed at least 4.5 but no more than 6 years of adjuvant tamoxifen after resection

          -  Completed at least 4.5-6 years of adjuvant aromatase inhibitor as initial therapy or
             after tamoxifen

          -  No more than 3 months since prior adjuvant tamoxifen

          -  No concurrent hormone replacement therapy (e.g., megestrol)

          -  No concurrent selective estrogen-receptor modulators (e.g., raloxifene or idoxifene)

          -  Concurrent intermittent vaginal estrogens (e.g., Estring) allowed if other local
             measures for intractable vaginal atrophy are insufficient

          -  No other concurrent aromatase inhibitors

          -  No more than 2 years since prior aromatase inhibitor therapy (re-randomization)

        Radiotherapy:

          -  Prior radiotherapy allowed

        Surgery:

          -  See Disease Characteristics

        Other:

          -  At least 1 month since prior investigational drugs

          -  Prior treatment on a clinical trial for breast cancer allowed if permission has been
             obtained from the sponsors of the original study for their patient to participate on
             MA.17/JMA.17/BIG-97-01

          -  No prior placebo on core protocol

          -  No concurrent anticancer therapy

          -  Concurrent thyroid medication, calcium, vitamin D, and bisphosphonates allowed