Optimization and Standardization of Single-Port Robotic Transanal Minimally Invasive Surgery for Rectal Tumor Excision

Title Case Summary: "This study evaluates the safety, feasibility, and short-term clinical outcomes of a new surgical approach called Single-Port (SP) Robotic Transanal Minimally Invasive Surgery (SPR TAMIS) for treating rectal tumors."

Content:

Transanal Minimally Invasive Surgery (TAMIS) is a standard technique for treating early-stage rectal tumors. However, traditional TAMIS often faces challenges such as restricted vision and instrument crowding in the narrow rectum.

The purpose of this study is to establish a standardized surgical procedure using a single-port robotic platform, which provides better flexibility and visualization. The investigators will analyze real-world clinical cases and surgical videos to assess key outcomes, including the success of tumor resection (R0 resection rate), operative safety, and patient recovery parameters. The study aims to provide clinical evidence for this robotic technique and facilitate its standardized implementation in surgical practice.

Study Overview

• Status: Active, not recruiting
• Conditions: Rectal Neoplasms; Rectal Cancer Patients; Rectal Benign Lesions
• Intervention / Treatment: Device: da Vinci SP Surgical System

Detailed Description

Transanal Minimally Invasive Surgery (TAMIS) is a key minimally invasive technique for the treatment of early-stage rectal tumors and selected rectal lesions. It offers advantages such as organ preservation, avoidance of abdominal incisions, reduced complications, and accelerated postoperative recovery. However, conventional TAMIS procedures are often limited by instrument crowding and restricted operative vision, especially within the narrow confines of the rectum.

The single-port robotic platform provides enhanced flexibility, articulation, and visualization, offering a promising solution to the technical challenges of transanal surgery. This study aims to establish a standardized surgical protocol for SP-assisted Robotic TAMIS (SPR TAMIS) and to evaluate its clinical safety, feasibility, and short-term outcomes.

The investigators will incorporate real-world clinical cases and intraoperative videos to perform procedural decomposition, analyze key surgical steps, assess R0 resection rates, and measure recovery-related parameters. In parallel, the project will develop a dedicated educational module and performance evaluation tools to support skill transfer and broader clinical implementation.

This project is expected to facilitate the standardization of the Robotic TAMIS workflow, provide evidence for its clinical efficacy, and build a structured training platform. This project will help establish a standardized framework for robotic transanal surgery, improve patient care through precise and less invasive techniques, and foster broader clinical integration of advanced robotic platforms within Taiwan's surgical practice.

• Study Type: Interventional
• Enrollment (Estimated): 20
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Taiwan
  • Taoyuan District, Taiwan, 333
    • Chang Gung Memorial Hospital, Linkou

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Patients with benign rectal lesions, including large adenomas or polyps not amenable to standard endoscopic removal
• Patients with recurrent or residual rectal lesions following incomplete endoscopic resection
• Patients with early-stage rectal cancer (clinical T1 tumors confined to the submucosa) with favorable histologic features (e.g., well-differentiated, no lymphovascular or perineural invasion)
• Select patients with T2 rectal cancer who are medically unfit for radical surgery or require local palliation
• Patients with clinically downstaged rectal cancer (e.g., cT0 or near-complete response) following neoadjuvant chemoradiotherapy, in whom TAMIS may be used for local excision to confirm pathological response

Exclusion Criteria:

• Patients undergoing excision of rectal neuroendocrine tumors
• Patients with bulky tumors or advanced disease (clinical T3-T4)
• Patients with radiologic or clinical evidence of nodal involvement
• Patients with high-risk histologic features (e.g., lymphovascular invasion, perineural invasion, poor differentiation), unless TAMIS is performed for palliative purposes or in patients unfit for radical surgery
• Patients in whom completion radical surgery is clearly indicated based on preoperative assessment

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: SPR TAMIS Group; Participants with early-stage rectal tumors or lesions undergoing Transanal Minimally Invasive Surgery (TAMIS) using a single-port robotic platform.	Device: da Vinci SP Surgical System; This intervention involves the use of a single-port robotic platform to perform transanal excision of rectal tumors. The procedure includes robotic docking, precise tumor dissection with wristed instrumentation, and robotic-assisted closure of the rectal defect.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of Participants With Procedure-Related Adverse Events	Number of participants experiencing procedure-related adverse events within 30 days after surgery, graded according to the Clavien-Dindo classification.	Within 30 days postoperatively

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of Standardized Surgical Steps Identified	Number of discrete procedural steps defined for SPR TAMIS based on intraoperative video analysis.	Throughout the study period (Expected 1 year)

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Surgical Competency in SPR TAMIS	Surgical competency will be evaluated using a structured, procedure-specific assessment framework during SPR TAMIS procedures performed in the training workshops. The evaluation will focus on key technical domains, including instrument control, dissection precision, maintenance of operative field exposure, procedural efficiency, and quality of defect closure. Assessments will be conducted by expert evaluators based on direct observation or recorded procedures. Improvement in competency over the training period will be used to reflect skill acquisition and technical proficiency.	Upon completion of the training workshops (Expected within 1-2 years)

Collaborators and Investigators

• Sponsor: Jeng-Fu You
• Investigators: Study Chair: JENG-FU YOU, Chang Gung Memorial Hospital

Study record dates

Study Major Dates

• Study Start (Actual): January 1, 2026
• Primary Completion (Estimated): December 31, 2026
• Study Completion (Estimated): December 31, 2029

Study Registration Dates

• First Submitted: December 24, 2025
• First Submitted That Met QC Criteria: April 3, 2026
• First Posted (Actual): April 13, 2026

Study Record Updates

• Last Update Posted (Actual): April 17, 2026
• Last Update Submitted That Met QC Criteria: April 14, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Keywords: Minimally Invasive Surgery; Robotic Surgery; Transanal Surgery; Natural Orifice Transluminal Endoscopic Surgery (NOTES); TAMIS (Transanal Minimally Invasive Surgery); Single-port Robot; SPR TAMIS
• Additional Relevant MeSH Terms: Neoplasms by Site; Neoplasms; Intestinal Diseases; Gastrointestinal Neoplasms; Digestive System Neoplasms; Digestive System Diseases; Gastrointestinal Diseases; Colorectal Neoplasms; Intestinal Neoplasms; Rectal Diseases; Rectal Neoplasms
• Other Study ID Numbers: 202501208A3

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No