Letrozole in Preventing Cancer in Postmenopausal Women Who Have Received 4-6 Years of Hormone Therapy for Hormone Receptor-Positive, Lymph Node-Positive, Early-Stage Breast Cancer
Condition: Breast Cancer
MeSH terms: Breast Neoplasms
Intervention: Letrozole; Letrozole
Intervention description: Film-coated tablet, oral use, 2.5 mg Letrozole daily for 5 years continuously; Film-coated tablet, oral use, 2.5 mg daily, 48 months over 5 yrs: 4 x 9 months (9 mo followed by 3 mo treatment-free interval in yrs 1-4, -> 36 mo) plus 1 x 12 mo in yr 5 -> 48 months
Intervention MeSH terms: Letrozole
Phase: Phase 3
Study type: Interventional
Primary purpose: Prevention
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Enrollment: 4884.0
Sex: Female
Minimum age: 18 Years
Maximum age: 120 Years
Healthy volunteers: No
Keywords: stage IA breast cancer; stage IB breast cancer; stage II breast cancer; stage IIIA breast cancer

Summary:

      RATIONALE: Estrogen can cause the growth of breast cancer cells. Letrozole may fight breast
      cancer by lowering the amount of estrogen the body makes. It is not yet known which regimen
      of letrozole is more effective in postmenopausal women who have received hormone therapy for
      early-stage breast cancer.

      PURPOSE: This randomized phase III trial is comparing two different regimens of letrozole in
      preventing cancer in postmenopausal women who have received 4-6 years of hormone therapy for
      hormone receptor-positive, lymph node-positive, early-stage breast cancer.
    

Eligibility criteria:

        DISEASE CHARACTERISTICS:

          -  Confirmed diagnosis of prior operable, noninflammatory breast cancer meeting the
             following criteria:

               -  Steroid hormone receptor-positive tumors (estrogen receptor and/or progesterone
                  receptor), determined by immunohistochemistry, after primary surgery and before
                  commencement of prior endocrine therapy

               -  Prior local treatment including surgery with or without radiotherapy for primary
                  breast cancer with no known clinical residual loco-regional disease

               -  Following primary surgery, eligible patients must have had evidence of lymph node
                  involvement either in the axillary or internal mammary nodes, but not
                  supraclavicular nodes

               -  Clinically disease-free

          -  Must have completed 4-6 years of prior adjuvant selective estrogen receptor modulators
             (SERMs), aromatase inhibitors (AIs), or a sequential combination of both

               -  When calculating 4-6 years, neoadjuvant endocrine therapy should not be included

          -  No evidence of recurrent disease or distant metastatic disease

          -  No prior bilateral breast cancer

        PATIENT CHARACTERISTICS:

          -  Female

          -  Must be postmenopausal by any of the following criteria:

               -  Patients of any age who have had a bilateral oophorectomy (including radiation
                  castration AND amenorrheic for > 3 months)

               -  Patients 56 years old or older with any evidence of ovarian function must have
                  biochemical evidence of definite postmenopausal status (defined as estradiol,
                  luteinizing hormone [LH], and follicle-stimulating hormone [FSH] in the
                  postmenopausal range)

               -  Patients 55 years old or younger must have biochemical evidence of definite
                  postmenopausal status (defined as estradiol, LH, and FSH in the postmenopausal
                  range)

                    -  Patients who have received prior luteinizing-hormone releasing-hormone
                       (LHRH) analogues within the last year are eligible if they have definite
                       evidence of postmenopausal status as defined above

          -  Clinically adequate hepatic function

          -  No bone fracture due to osteoporosis at any time during the 4-6 years of prior therapy

          -  No prior or current malignancy except adequately treated basal cell or squamous cell
             carcinoma of the skin, in situ carcinoma of the cervix or bladder, or contra- or
             ipsilateral in situ breast carcinoma

          -  No other nonmalignant systemic diseases (cardiovascular, renal, lung, etc.) that would
             prevent prolonged follow-up

          -  No psychiatric, addictive, or any other disorder that compromises compliance with
             protocol requirements

        PRIOR CONCURRENT THERAPY:

          -  See Disease Characteristics

          -  More than 12 months since prior and no other concurrent endocrine SERM/AI therapy

          -  Any type of prior adjuvant therapy allowed including, but not limited to, any of the
             following:

               -  Neoadjuvant chemotherapy

               -  Neoadjuvant endocrine therapy

               -  Adjuvant chemotherapy

               -  Trastuzumab (Herceptin®)

               -  Ovarian ablation

               -  Gonadotropin releasing hormone analogues

               -  Lapatinib ditosylate

          -  No concurrent hormone-replacement therapy, bisphosphonates (except for treatment of
             bone loss), or any other investigational agent