First Clinical Experience With Single-Port Robotic Transanal Minimally Invasive Surgery: Phase II Trial of the Initial 26 Cases

BACKGROUND: Many transanal platforms have been developed to address the challenge of reach and vision when operating transanally. The single-port robot was specifically designed for narrow-aperture surgery and is a promising platform for minimally invasive transanal surgery. OBJECTIVE: The purpose of this phase II trial is to evaluate the safety and feasibility of the initial clinical experience with single-port robot transanal minimally invasive surgery. DESIGN: In a prospective phase II trial, patients with rectal neoplasms eligible for local excision were enrolled for single-port robotic transanal minimally invasive surgery. SETTING: The study was conducted between October 2018 and March 2020 at a tertiary referral hospital. PATIENTS/INTERVENTION: Twenty-six consecutive patients underwent single-port robotic transanal minimally invasive surgery resection of rectal lesions. MAIN OUTCOME MEASURES: The primary end point of the study was the efficacy and safety of single-port robotic transanal minimally invasive surgery. RESULTS: There were 13 men and 13 women, with an average lesion size of 2.9 cm (range, 1.0-6.0 cm) and average level of 4.8 cm from the anorectal ring (range, 0-30 cm). Ten patients had a preoperative diagnosis of adenocarcinoma, 7 of whom received neoadjuvant chemoradiation (range, 4500-5580 cGy with concurrent oral capecitabine). Eighty-eight percent of cases were completed by single-port robotic transanal minimally invasive surgery; 2 were converted to transanal endoscopic microsurgery, and 1 patient underwent a low anterior resection. There were no piecemeal extractions, and all margins were negative on final pathology. There were no mortalities, and the morbidity rate was 15.4%. There have been no local recurrences, with a mean follow-up of 5.8 months (range, 0-15.9 months). LIMITATIONS: The study was limited by small sample size, short-term follow up, and a single-surgeon experience. CONCLUSION: Single-port robotic transanal minimally invasive surgery procedures are safe and feasible in patients with select benign and malignant rectal lesions. Future trials will need to evaluate the long-term safety and efficacy of single-port robotic transanal minimally invasive surgery.