Please assess the completion status of the following clinical trial:

Trial Title: Effect of Dexamethasone in Postoperative Symptoms After Mastectomy for Breast Cancer

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

Eligibility Criteria:
Inclusion Criteria:~* American Society of Anesthesiologists classes I-II female patients with breast cancer scheduled for surgical treatment; mastectomy plus axillary node dissection.~Exclusion Criteria:~* American Society of Anesthesiologists classes III and IV.~* Age more than 80 years; pregnancy; active menstruation; treatment with steroids; severe diabetes mellitus (serum HbA1c \> 8%); use of opioids, sedatives or any kind of analgesics less than one week before mastectomy, or a history of alcohol or drug abuse.~* Patients with any history of motion sickness and or previous postoperative nausea and vomiting after any surgical procedure.

- Gender: FEMALE
- Minimum Age: 18 Years
- Maximum Age: 79 Years
- Healthy Volunteers: f

Study Arms:
- Dexamethasone group (Type: ACTIVE_COMPARATOR): This group of patients received intravenous dexamethasone (8 mg) 60 minutes before skin incision.
- Placebo group (Type: PLACEBO_COMPARATOR): Patients of these group received homologated placebo 60 minutes before skin incision.

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