Please assess the completion status of the following clinical trial:

Trial Title: Anastrozole or Tamoxifen in Treating Postmenopausal Women With Ductal Carcinoma in Situ Who Are Undergoing Lumpectomy and Radiation Therapy

Study Design Characteristics:
- Allocation: RANDOMIZED
- Intervention Model: PARALLEL
- Observational Model: None
- Primary Purpose: TREATMENT
- Time Perspective: None
- Masking: QUADRUPLE
- Phase: PHASE3
- Number of Arms: 2.0

Eligibility Criteria:
DISEASE CHARACTERISTICS:~* Histologically confirmed ductal carcinoma in situ (DCIS) of the breast~  * Mixed DCIS and lobular carcinoma in situ (LCIS) allowed~* Must have undergone lumpectomy~  * Margins must be histologically free of disease~ * Re-excision to obtain tumor-free margins allowed~ * No more than 84 days since prior lumpectomy or re-excision~* More than 1 area of DCIS allowed provided all disease is removed with tumor-free margins~  * Masses or clusters of calcification that are clinically or mammographically suspicious must be biopsied~* No prior invasive breast cancer or DCIS~  * Patients with a history of LCIS are eligible~* No prior or concurrent invasive (including microinvasive) breast cancer~  * DCIS suspicious for microinvasion allowed~* No bilateral malignancy~  * No mass or mammographic abnormality suspicious for malignancy in the opposite breast unless not malignant as proven by biopsy~* No Paget's disease of the nipple~* No positive ipsilateral axillary or intramammary nodes~  * No palpable nodes in the ipsilateral or contralateral axilla or palpable supraclavicular or infraclavicular nodes unless not involved with tumor as proven by biopsy~* Hormone receptor status:~  * Estrogen- or progesterone-receptor positive as determined by immunohistochemistry~    * Borderline results are considered positive~PATIENT CHARACTERISTICS:~Age~* See Menopausal status~Sex:~* Female~Menopausal status:~* Postmenopausal as defined by at least 1 of the following:~  * Prior documented bilateral oophorectomy~ * At least 12 months without spontaneous bleeding~ * Age 55 or over with prior hysterectomy without oophorectomy~ * Age 54 or under with prior hysterectomy without oophorectomy with a documented follicle-stimulating hormone level in the postmenopausal range~Performance status~* Zubrod 0-2~Life expectancy~* At least 10 years (excluding diagnosis of breast cancer)~Hematopoietic~* WBC normal~Hepatic~* AST normal~* Bilirubin normal~* Alkaline phosphatase normal~* No hepatic disease that would preclude administration of study drugs~Renal~* Creatinine normal~* No renal disease that would preclude administration of study drugs~Cardiovascular~* No prior documented cerebral vascular accident or transient ischemic attack~* No prior deep vein thrombosis~* No cardiovascular disease that would preclude administration of study drugs~* No uncontrolled hypertension (i.e., systolic blood pressure at least 180 mm Hg or diastolic blood pressure at least 110 mm Hg based on the average of 2 or more readings at each of 2 or more visits after initial screening)~* No uncontrolled atrial fibrillation~Pulmonary~* No pulmonary embolus~Other~* Not pregnant or nursing~* Patients with a history of non-breast malignancies are eligible provided they have been disease-free for ≥ 5 years and are deemed by their physician to be at low risk for recurrence~* No other malignancy within the past 5 years except treated basal cell or squamous cell skin cancer, carcinoma in situ of the cervix, carcinoma in situ of the colon, or melanoma in situ~* No psychiatric or addictive disorders that would preclude informed consent~* No uncontrolled diabetes, defined as hemoglobin A1C greater than 9% (fasting glucose 200 mg/dL)~* No nonmalignant systemic disease that would preclude administration of study drugs~PRIOR CONCURRENT THERAPY:~Endocrine therapy~* No prior or concurrent aromatase inhibitors (e.g., exemestane or letrozole) or tamoxifen~* No concurrent raloxifene or other selective estrogen receptor modulators~* No concurrent sex hormone therapy (e.g., estrogen or progesterone replacement therapy, oral contraceptives, androgens, luteinizing hormone releasing hormone analogs, prolactin inhibitors, or antiandrogens)~  * Low-dose estrogen vaginal creams or Estring allowed~Radiotherapy~* Radiotherapy for this cancer initiated before study is allowed~Surgery~* See Disease Characteristics~* No prior or concurrent mastectomy for DCIS~* Prior sentinel node biopsy or axillary node dissection allowed provided nodes are pathologically negative~Other~* No concurrent warfarin~* No other systemic therapy for this cancer initiated before study~* No other concurrent anticancer therapy unless permitted by the protocol investigator~* No concurrent participation in another clinical trial of therapy for DCIS~  * Concurrent participation in protocol NSABP-B-39 allowed

- Gender: FEMALE
- Minimum Age: None
- Maximum Age: None
- Healthy Volunteers: f

Study Arms:
- Group 1 (Type: ACTIVE_COMPARATOR): tamoxifen 20 mg/day and an anastrozole look-alike placebo for 5 years
- Group 2 (Type: EXPERIMENTAL): anastrozole, 1 mg/day and an tamoxifen look-alike placebo for 5 years

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

Answer: outcome: complete