Please assess the completion status of the following clinical trial:

Trial Title: Imatinib Mesylate or Observation Only in Treating Patients Who Have Undergone Surgery for Localized Gastrointestinal Stromal Tumor

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

Eligibility Criteria:
DISEASE CHARACTERISTICS:~* Histologically confirmed gastrointestinal stromal tumor~  * Localized disease~* Meets 1 of the following criteria:~  * At high-risk of relapse, defined by 1 of the following criteria:~    * Tumor size \> 10 cm~   * Mitotic rate \> 10/50 high-power field (HPF)~   * Tumor size \> 5 cm AND mitotic rate \> 5/50 HPF~ * At intermediate-risk of relapse, defined by 1 of the following criteria:~    * Tumor size \< 5 cm AND mitotic rate 6-10/50 HPF~   * Tumor size 5-10 cm AND mitotic rate \< 5/50 HPF~* Tumor must stain positive for Kit (CD117) by polyclonal DAKO antibody staining~* Must have undergone complete resection of the primary tumor at least 2 weeks, but no more than 3 months, before study entry~  * Meets criteria for 1 of the following resection levels:~    * R0 (clear margins)~   * R1, defined by 1 of the following criteria:~      * Margins of resection are contaminated by tumor, but no macroscopic tumor is left behind~     * Intraoperative tumor rupture~     * Shelling-out procedure~     * Endoscopic maneuver~ * No residual macroscopic disease after surgery~    * Regional positive lymph nodes allowed provided they have been macroscopically excised~* No distant metastases\*, including any of the following:~  * Peritoneal lesion not contiguous to the primary tumor~ * Liver metastases~ * Hemoperitoneal metastases NOTE: \*Even if a complete resection (R0) was performed~PATIENT CHARACTERISTICS:~Age~* 18 and over~Performance status~* WHO 0-2~Life expectancy~* Not specified~Hematopoietic~* Absolute neutrophil count ≥ 1,500/mm\^3~* Platelet count ≥ 100,000/mm\^3~* Hemoglobin ≥ 9 g/dL (transfusions allowed)~Hepatic~* Bilirubin ≤ 1.5 times upper limit of normal (ULN)~* AST or ALT ≤ 2.5 times ULN~* No uncontrolled liver disease~* No chronic viral hepatitis at risk of reactivation~Renal~* Creatinine \< 1.5 times ULN~* No uncontrolled chronic renal disease~Cardiovascular~* No New York Heart Association class III-IV cardiac disease~* No congestive heart failure~* No myocardial infarction within the past 2 months~Other~* Not pregnant or nursing~* Negative pregnancy test~* Fertile patients must use effective contraception during and for up to 3 months after study participation~* No uncontrolled diabetes~* No uncontrolled active infection~* No HIV infection~* No psychological, familial, sociological, or geographical condition that would preclude study compliance or participation~* No other severe and/or uncontrolled medical disease~* No other malignancy within the past 5 years except adequately treated basal cell or squamous cell skin cancer or carcinoma in situ of the cervix~PRIOR CONCURRENT THERAPY:~Biologic therapy~* No other prior molecular targeted or biologic therapy~* No concurrent filgrastim (G-CSF) or sargramostim (GM-CSF) to support blood counts~* No concurrent anticancer biologic agents~Chemotherapy~* No prior chemotherapy for gastrointestinal stromal tumors~* No concurrent anticancer chemotherapy~Endocrine therapy~* Not specified~Radiotherapy~* No prior radiotherapy~* No concurrent anticancer radiotherapy~Surgery~* See Disease Characteristics~* Prior non-curative surgery allowed (e.g., surgery with main diagnostic intent or emergency surgery with symptomatic intent)~Other~* No prior imatinib mesylate~* No prior randomization to this study~* No concurrent therapeutic anticoagulation with coumarin derivatives~  * Concurrent therapeutic low-molecular weight heparin or mini-dose coumarin derivatives (equivalent to oral warfarin 1 mg/day) allowed for prophylaxis of central venous catheter thrombosis~* No other concurrent antitumoral therapy~* No other concurrent anticancer agents~* No other concurrent investigational drugs

- Gender: ALL
- Minimum Age: 18 Years
- Maximum Age: 120 Years
- Healthy Volunteers: f

Study Arms:
- Imatinib mesylate (Type: EXPERIMENTAL): 400 mg/day for 2 years
- Control (Type: NO_INTERVENTION): None

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