Here is the design of a clinical trial:

Official Title: Oncologic oUTcomes of Neoadjuvant Chemotherapy for obSTructive Colon cAncer After steNt Decompression (OUTSTAND Trial); Multicenter Randomized Controlled Trial

Included conditions:
- Colon Cancer, Obstruction

Study Armgroups:
- {'label': 'The Control group', 'type': 'ACTIVE_COMPARATOR', 'description': '- The patients who are assigned into control group take a curative surgery within 2 weeks after successful SEMS placement. And then, after recovery period, adjuvant FOLFOX chemotherapy will be administered into them. Adjuvnat FOLFOX chemotherapy will be administered every 2week during 6 months (total 12 cycles).', 'interventionNames': ['Drug: Adjuvant chemotherapy', 'Procedure: Curative resection']}
- {'label': 'The Experimental group', 'type': 'EXPERIMENTAL', 'description': '- The patients who are assigned into the experimental group take a neoadjuvant FOLFOX chemotherapy within 2 weeks after successful SEMS placement. After three cycles of FOLFOX, they will take a curative surgery. And then, after recovery period, adjuvant FOLFOX chemotherapy will be administered into them. Adjuvnat FOLFOX chemotherapy will be administered every 2week during about 4 months (total 9 cycles). The perioperative FOLFOX chemotherapy in the experimetal group will be totally 12 cycles during 6months.', 'interventionNames': ['Drug: Neoadjuvant chemotherapy', 'Drug: Adjuvant chemotherapy', 'Procedure: Curative resection']}

Interventions:
- {'type': 'DRUG', 'name': 'Neoadjuvant chemotherapy', 'description': 'In this study, patients with obstructive colon cancer will be divided into two groups; in the control group, curative surgery will be performed within 2 weeks after successful SEMS placement, and in the experimental group, 3 cycles of neoadjuvant chemotherapy will be administered into patients who undergo successful SEMS placement and then curative surgery will be performed after neoadjuvnat chemotherapy. After the surgery, adjuvant chemotherapy will be administered, and total perioperative chemotherapy will be administered with 12 cycles.', 'armGroupLabels': ['The Experimental group'], 'otherNames': ['Curative surgery']}
- {'type': 'DRUG', 'name': 'Adjuvant chemotherapy', 'description': 'After the surgery, adjuvant chemotherapy will be administered, and total perioperative chemotherapy will be administered with 12 cycles.', 'armGroupLabels': ['The Control group', 'The Experimental group'], 'otherNames': ['curative surgery']}
- {'type': 'PROCEDURE', 'name': 'Curative resection', 'description': 'After successful SEMS placement, curate resection will be performed for all enrolled patients regardless of neoadjuvant chemotherapy.', 'armGroupLabels': ['The Control group', 'The Experimental group']}

Primary Outcomes:
- {'measure': '3-year overall survival', 'description': '3-year overall survival after curative surgery', 'timeFrame': '3 years after surgery'}

Please estimate the sample size based on the assumption: 
The study uses a non-inferiority log-rank test with a significance level of 0.050 and 80.1% power to detect an equivalence hazard ratio of 2.29, assuming the actual hazard ratio is 1.00 and the hazard rate of the reference group is 0.0446. The study duration is six years, with uniform subject accrual over the first three years. The dropout rate for both control and experimental groups is 0.0100. The failure rate for stents is 8%, and the failure rate for screening is 15%.
Sample size and randomization
        Based on our retrospective analysis, the 5-year overall survival (OS) rate for the control group was 84.1%. However, for patients who underwent curative surgery 4 weeks after SEMS placement without neoadjuvant chemotherapy, the OS rate was only 37.5%. The maximum response rate was assumed to be 80.0%, while the minimum response rate was assumed to be 40.0%. The non-inferiority limit for this study was set at 20%, which is half of 40%. Additionally, a non-inferiority margin of 60% was established. We determined the noninferiority margin for our study based on clinical judgment and retrospective data. We have chosen the noninferiority test as a method to minimize the unrealistic overall survival difference resulting from such a significant gap. We have set the non-inferiority limit for this study at 20%, which is relatively large. However, we believed that a 20% increase in OS with neoadjuvant therapy is possible and realistic, even though it is not a small number. Although it is generally advisable to choose a smaller value for the noninferiority margin, the feasibility of study recruitment was another important factor to consider. Therefore, we selected the noninferiority margin equivalent to a 20% increase in the expected OS rate. A non-inferiority log-rank test was conducted with a total sample size of 204 subjects, evenly divided between the control and experimental groups. The test achieved 80.1% power at a significance level of 0.050 to detect an equivalence hazard ratio of 2.29, assuming the actual hazard ratio is 1.00 and the hazard rate of the reference group is 0.0446. The study will last for six years, during which subject accrual (entry) will occur within the first three years. The accrual pattern is uniform across all time periods; all years are equal. The proportion of participants dropping out of the control group is 0.0100. The proportion of participants dropping out of the experimental group is 0.0100. The proportion of individuals switching from the control group to another group with a hazard rate equal to that of the experimental group is 0.0000. The proportion of individuals switching from the experimental group to another group with a hazard rate equal to that of the reference group is 0.0000. The estimated failure rate for stents is 8%. And, the failure rate for screening - indicating synchronous malignancies at other sites or patients requiring emergency operations - is 15%. A total of over 260 patients will be screened for the successful trial.
        After the successful placement of self-expandable metal stents (SEMS), random allocation will be carried out with the consent of patients and their guardians. A total of 204 patients will be evenly distributed between the two groups in a 1:1 ratio. This study is a multicenter, randomized (1:1), parallel-group, open-label, controlled clinical trial. Using a random-number table, assignment codes will be concealed in opaque envelopes. To avoid the issue of tampering with the allocation from the sealed envelopes, the sealed opaque envelopes containing the randomization card, which is not visible through transillumination, are stored at the trial administration center (St. Vincentâs Hospital, Suwon, Korea). They are opened by a third party immediately after receiving a telephone call from the clinician who wishes to enroll a patient, in order to minimize the risk of allocation manipulation. The sealed envelopes will be used but will be open by a centralized system. Half of the patients will be randomly assigned to the control group, while the other half will be assigned to the experimental group through randomization.