Single-Incision Versus Conventional Laparoscopic Appendectomy: A Multi-Center Randomized Controlled Trial (SCAR trial).

Introduction: Although single-incision laparoscopic appendectomy (SILA) was introduced decades ago, it is still considered a difficult technique to perform compared to conventional laparoscopic appendectomy (CLA). In addition, controversy about the benefits of SILA compared to CLA abound and no definite criteria for choosing SILA over CLA in patients with appendicitis currently exist. Therefore, we have planned a multi-center randomized controlled trial to compare SILA with CLA in terms of cosmetic satisfaction and pain reduction.

Methods and analysis: Patients diagnosed with appendicitis at the participating centers will be recruited and allocated into either a CLA or an SILA groups using a 1:1 randomization. Patients in the CLA group will receive a conventional 3-port laparoscopic appendectomy and patients in the SILA group will receive a laparoscopic appendectomy using a single-incision at the umbilicus. The primary trial endpoint is cosmetic satisfaction assessed using the Patients and Observer Scar Assessment Scale (POSAS) administered 6 weeks post-surgery. Secondary trial endpoints include cosmetic satisfaction assessed via the Body Image Questionnaire, pain levels assessed via the Visual Analog Scale and International Pain Outcomes questionnaire, and the presence of postoperative complications. The target sample size of this superiority trial is 120 patients, as this will provide 80% power at the 2.5% level of significance to detect a 3-point difference in POSAS.

Discussion: The results of this planned multi-center randomized controlled trial will provide substantive evidence to help surgeons choose when to use SILA over CLA in patients with appendicitis.

Ethics and dissemination: This trial was approved by the institutional review board at Daegu joint on February 27, 2020 (No: 19-12-001-001) and registered with the clinical research information service (CRIS) (KCT0005048). The results of the study will be published and presented at appropriate conferences.

Highlights: To investigate the clinical benefits comparing between single incision laparoscopic appendectomy and conventional laparoscopic appendectomyTo assess the pain and cosmetic satisfaction through quantitative scales, Patient-Reported Outcomes Measures (PROMs), International Pain Outcome (IPO) Questionnaire, the Patient and Observer Scar Assessment Scale (POSAS), and the Body Image Questionnaire (BIQ)To help surgeons choose when to use single incision laparoscopic appendectomy in patients with appendicitis.