Here is the design of a clinical trial:

Official Title: Oncologic Outcomes of Single-incision Laparoscopic Surgery Versus Conventional Laparoscopic Surgery for Colorectal Cancer: A Multi-center, Prospective, Open Label, Non-inferiority, Randomized Controlled Trial

Included conditions:
- Colorectal Cancer
- Colon Cancer
- Rectal Cancer

Study Armgroups:
- {'label': 'Single-incision Laparoscopic Surgery', 'type': 'EXPERIMENTAL', 'description': 'Patients with colorectal cancer undergo single-incision laparoscopic surgery.', 'interventionNames': ['Procedure: Single-incision Laparoscopic Surgery']}
- {'label': 'Conventional Laparoscopic Surgery', 'type': 'ACTIVE_COMPARATOR', 'description': 'Patients with colorectal cancer undergo conventional laparoscopic surgery（3\\~5 ports）.', 'interventionNames': ['Procedure: Conventional Laparoscopic Surgery']}

Interventions:
- {'type': 'PROCEDURE', 'name': 'Single-incision Laparoscopic Surgery', 'description': 'In this group，the surgery is performed through a single incision. The surgeon will adjust surgical position to expose the operative field with the help of gravity. Besides，hand over hand cross and parallel techniques are needed to achieve the SILS. All the other operative procedures are the same as conventional laparoscopic surgery.', 'armGroupLabels': ['Single-incision Laparoscopic Surgery'], 'otherNames': ['SILS']}
- {'type': 'PROCEDURE', 'name': 'Conventional Laparoscopic Surgery', 'description': 'In this group，the surgery is performed through 3-5 ports according to the surgeons habits and specific conditions.', 'armGroupLabels': ['Conventional Laparoscopic Surgery'], 'otherNames': ['CLS']}

Primary Outcomes:
- {'measure': '3-year disease free survival rate', 'description': '3-year disease free survival rate', 'timeFrame': '36 months after surgery'}

Please estimate the sample size based on the assumption: 
The unilateral statistical significance level is 0.025, the power is 80%, and the study group and the control group will be allocated in a 1:1 ratio. The largest dropout rate is approximately 20%.
Sample size calculation
        In this study, the 3-year DFS is the main effectiveness evaluation index for noninferiority evaluation. According to previous studies [27â29], the 3-year DFS of the CLS group was approximately 75%. This study assumes that the 3-year DFS of the study group is the same as that of the control group. The expected enrolment time is 3Â years, and the follow-up time to reach the primary endpoint is 3Â years. If the acceptable noninferiority limit of DFS in the three years of this study is 10%, when DFS is exponentially distributed, the corresponding HR limit is 1.49. This number will be combined with "Log-Rank Tests for Noninferiority" in the professional sample size estimation software NCSS-PASS (14th edition, NCSS, LLC, Utah, USA). When the unilateral statistical significance level is 0.025, the inspection efficiency is 80%, and the study group and the control group will be allocated in the ratio of 1:1, the required sample size of each group will be 284. Considering that the largest abscission rate in this clinical study is approximately 20%, it was finally determined that the sample size of each group will be 355 cases, and the total number of cases required will be 710.