Letrozole in Breast Cancer Who Have Received 5 Years of Aromatase Inhibitor Therapy

• Status: Completed
• Trial end date: 2017-04-19
• Target enrollment: 0
• Participant gender: Female

Summary

RATIONALE: Estrogen can cause the growth of breast cancer cells. Hormone therapy using letrozole may fight breast cancer by lowering the amount of estrogen the body makes. It is not yet known whether letrozole is more effective than a placebo in treating in women with breast cancer who have already received 5 years of aromatase inhibitor therapy.

PURPOSE: This randomized phase III trial is studying letrozole to see how well it works compared with a placebo in treating women with primary breast cancer who have received 5 years of aromatase inhibitor therapy.

• Phase: Phase 3
• Accepts Healthy Volunteers?: No

Details

• Lead Sponsor: Canadian Cancer Trials Group
• Collaborators: Alliance for Clinical Trials in Oncology; Eastern Cooperative Oncology Group; North Central Cancer Treatment Group; Southwest Oncology Group
• Treatments: Aromatase Inhibitors; Letrozole

Criteria

DISEASE CHARACTERISTICS:

• Previously diagnosed with primary breast cancer

• Must have received 4½ - 6 years of aromatase inhibitor therapy (e.g., letrozole, anastrozole, or exemestane), either as initial therapy or after prior tamoxifen citrate, including treatment received as part of clinical trial CAN-NCIC-MA17

• Completed aromatase inhibitor therapy ≤ 2 years ago

• No metastatic or recurrent disease, contralateral breast cancer, or ductal carcinoma in situ in either breast, as determined by the following:

• Clinical examination of the breast area, axillae, and neck within the past 60 days

• Mammogram within the past 12 months*

• Chest x-ray within the past 60 days

• Bone scan, if alkaline phosphatase > 2 times normal and/or there are symptoms of metastatic disease AND confirmatory x-ray, if bone scan results are questionable, within the past 60 days

• Abdominal ultrasound, liver scan, or CT scan of the abdomen within the past 60 days, if ALT, AST, or alkaline phosphatase > 2 times normal NOTE: *A baseline mammogram is not required for patients who have undergone bilateral complete mastectomy

• Hormone-receptor status:

• Estrogen receptor positive (ER+) and/or progesterone receptor positive (PR+) primary tumor at the time of diagnosis, defined as a tumor receptor content of > 10 fmol/mg protein or receptor positive by immunocytochemical assay (for patients not previously enrolled on clinical trial CAN-NCIC-MA17)

• ER+ and/or PR+ primary tumor OR hormone receptor status of primary tumor unknown (for patients previously enrolled on clinical trial CAN-NCIC-MA17)

PATIENT CHARACTERISTICS:

• Menopausal status not specified

• ECOG performance status 0-2

• Life expectancy ≥ 5 years

• WBC > 3.0 x 10^9/L OR granulocyte count (polymorphs + bands) ≥ 1.5 times 10^9/L

• Platelet count > 100 x 10^9/L

• AST and/or ALT < 2 times upper limit of normal (ULN)*

• Alkaline phosphatase < 2 times ULN*

• Able (i.e. sufficiently fluent) and willing to complete quality-of-life questionnaires in either English or French (NCIC CTG participating centers)

• Inability to complete questionnaires due to illiteracy in English or French, loss of sight, or other equivalent reason allowed

• Accessible for treatment and follow-up

• No other prior or concurrent malignancy except adequately treated, superficial squamous cell or basal cell skin cancer, carcinoma in situ of the cervix, or other cancer treated > 5 years ago that is presumed cured NOTE: *Elevated levels allowed provided imaging examinations have ruled out metastatic disease

PRIOR CONCURRENT THERAPY:

• See Disease Characteristics

• No concurrent selective estrogen receptor modulator (e.g., raloxifene, idoxifene)

• No other concurrent anticancer therapy