Please assess the completion status of the following clinical trial:

Trial Title: Letrozole in Preventing Breast Cancer in Postmenopausal Women

Study Design Characteristics:
- Allocation: RANDOMIZED
- Intervention Model: PARALLEL
- Observational Model: None
- Primary Purpose: PREVENTION
- Time Perspective: None
- Masking: DOUBLE
- Phase: PHASE2
- Number of Arms: 2.0

Eligibility Criteria:
DISEASE CHARACTERISTICS:~* At increased risk for the development or recurrence of breast cancer, defined as an estradiol level ≥ 9 pg/mL~* No evidence of suspicious or malignant disease, based on the following examinations:~  * Clinical bilateral breast examination within the past 6 months~ * Bilateral\* mammogram within 3 months before randomization OR within 30 days after randomization~ * Pelvic exam normal within the past 5 years~ * General physical exam within the past 6 months NOTE: \*Unilateral mammogram of the uninvolved breast for patients with prior invasive breast cancer or ductal carcinoma in situ (DCIS)~* Bone density scan within 2 standard deviations from normal within the past 30 days~  * Bone density scan ≥ 2 standard deviations below normal allowed if approved by the study physician~* At least 1 breast that has not been previously treated with radiotherapy or surgery (for patients with prior invasive breast cancer or DCIS)~* Hormone receptor status:~  * Not specified~PATIENT CHARACTERISTICS:~Age~* 35 and over~Sex~* Female~Menopausal status~* Postmenopausal, defined by any of the following criteria:~  * At least 12 months without spontaneous menstrual bleeding~ * Prior hysterectomy and bilateral salpingo-oophorectomy~ * ≥ 55 years of age with a prior hysterectomy with or without oophorectomy~ * \< 55 years of age with a prior hysterectomy without oophorectomy OR the status of the ovaries is unknown AND follicle-stimulating hormone (FSH) level is in the postmenopausal range~Performance status~* Normal activity must not be restricted for a significant portion of the day~Life expectancy~* At least 10 years~Hematopoietic~* Complete blood count with differential normal~  * Prior benign neutropenia allowed provided the granulocyte count is ≥ 1,500/mm\^3~Hepatic~* Bilirubin normal~* Alkaline phosphatase normal~* SGOT and SGPT normal~Renal~* Creatinine normal~Cardiovascular~* No uncontrolled cardiovascular disease~Other~* Not pregnant~* No other malignancy within the past 5 years except basal cell or squamous cell skin cancer or carcinoma in situ of the cervix~* No osteoporosis~* No hyperlipidemia~* No mental health status resulting in cognitive or emotional impairment that would preclude study participation~PRIOR CONCURRENT THERAPY:~Biologic therapy~* Not specified~Chemotherapy~* Not specified~Endocrine therapy~* More than 30 days since prior AND no concurrent use of any of the following hormonal agents:~  * Estrogen or progesterone replacement therapy~ * Oral contraceptives~ * Raloxifene or other plasma estrogen receptor modulators (SERMs)~ * Androgens (e.g., danazol)~ * Luteinizing hormone-releasing hormone (LHRH) analogs (e.g., goserelin or leuprolide)~ * Prolactin inhibitors (e.g., bromocriptine)~ * Antiandrogens (e.g., cyproterone)~* More than 60 days since prior AND no concurrent tamoxifen~* No prior aromatase inhibitors (for patients with prior invasive breast cancer or DCIS)~* No concurrent phytoestrogenic dietary supplements (e.g., soy, ginseng, or other natural products)~  * Dietary soy allowed~Radiotherapy~* See Disease Characteristics~Surgery~* See Disease Characteristics~* No prior bilateral mastectomy~Other~* More than 60 days since prior treatment for invasive breast cancer or DCIS~* More than 30 days since prior bisphosphonates or calcitonin~* No prior or concurrent participation on a treatment study for invasive breast cancer or DCIS~* No concurrent participation in any other cancer prevention study or osteoporosis prevention study involving pharmacologic agents~* No concurrent calcitonin~* No concurrent bisphosphonate therapy~* Concurrent cholecalciferol (vitamin D) and calcium to augment bone mineral density allowed

- Gender: FEMALE
- Minimum Age: 35 Years
- Maximum Age: 120 Years
- Healthy Volunteers: f

Study Arms:
- Letrozole (Type: EXPERIMENTAL): Participants in this arm received 2.5 mg of letrozole per day for a duration of 12 months; followed by an optional 4 years. Treatment continued in the absence of unacceptable toxicity or diagnosis of invasive breast cancer, ductal carcinoma in situ, or any non-breast primary cancer.
- Placebo (Type: PLACEBO_COMPARATOR): Participants in this arm received 1 tablet per day which contained the inert ingredients from the letrozole tablet, for a duration of 12 months; followed by an optional 5 years of letrozole.Treatment continued in the absence of unacceptable toxicity or diagnosis of invasive breast cancer, ductal carcinoma in situ, or any non-breast primary cancer.

Based on this trial design, predict the completion outcome and termination type (if applicable).

Answer: outcome: complete