Surgical and Patient Reported Outcomes in Robotic Mastectomy

Pilot Robotic Mastectomy in Singapore (PRoMiSing I) Study: First Safety and Feasibility Prospective Cohort Study in South East Asia

Conventional nipple and/or skin-sparing mastectomy (NSM/SSM) with or without immediate reconstruction is becoming one of the mainstream surgical treatment for breast cancer and risk reducing mastectomy in recent years. While this technique provides satisfactory oncologic and aesthetic outcomes, its disadvantages include skin flap and/or nipple-areolar complex (NAC) necrosis, NAC malposition/distortion as well as visible scar(s) on the breast.

In terms of technical aspects, NSM/SSM has its inherent challenges in view of limited incisions and thereby difficulties in dissection. Since 2015, a number of institutions worldwide had adopted a new technique of NSM/SSM using robotic surgical system. Institutional experiences worldwide demonstrated feasibility and safety of this technique coupled with improved patients' satisfactions.

To date, there is no center in Singapore or the region offering Robotic NSM/SSM (R-NSM/R-SSM). The authors believe that robotic mastectomy is a feasible and safe technique that can be utilized in our institution and it provides superior aesthetic outcomes with less morbidity and higher patient satisfaction if compared to conventional NSM/SSM.

The aim of this study is to conduct a single-arm prospective pilot study to investigate the safety and feasibility as well as learning curve of R-NSM/R-SSM.

Study Overview

• Status: Completed
• Conditions: Breast Cancer
• Intervention / Treatment: Procedure: Robotic mastectomy

• Study Type: Interventional
• Enrollment (Actual): 29
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Singapore
  • Singapore, Singapore, 529889
    • Changi General Hospital

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Women aged 21-70, with invasive breast cancer, ductal carcinoma in situ (DCIS), Breast Cancer (BRCA) gene or other breast cancer genetic mutation carriers or high risk female patients who are otherwise candidates for conventional NSM/SSM will be eligible for the study. All suitable patients will be offered the option of R-NSM/ R-SSM.

For patients with breast cancer (invasive or DCIS), selection criteria include but not limited to:

1. Early breast cancer
2. Tumor size less than 5 cm
3. No evidence of lymph node metastases
4. No evidence of skin or chest wall invasion.

Exclusion Criteria:

1. Extensive axillary lymph node metastasis (Stage 3B or later)
2. Heavy smokers (>20 cigarettes a day)
3. High risk patient with severe and poorly controlled co-morbid conditions (include but not limited to diabetes, heart disease, renal failure or liver dysfunction)
4. Poor performance status or high risk for anaesthesia (ASA 3 and above)
5. Inflammatory or Locally Advanced Breast Cancer (with or without chest wall or skin invasion)

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
Other: Robotic mastectomy; All consecutive cases of robotic mastectomy over the study duration	Procedure: Robotic mastectomy; Robotic mastectomy with or without reconstruction

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Surgical Outcomes - Operative parameters	- Operative parameters (in terms of docking time/console time and total operative time - defined as time taken from axilla staging procedure, robot docking time, console time, closure and time taken for reconstruction, if applicable	Postoperative Day 0-1
Surgical Outcomes - Length of stay (days)	- Length of stay (days)	Postoperative 30 days
Surgical Outcomes- 30-days morbidity/complications	- 30-days morbidity/complications	Postoperative 30 days

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Oncologic outcomes	Short-term oncologic outcomes, such as positivity of margins	Postoperative 2 weeks until final histopathology results are available
Learning curve	Learning curve analysis using cumulative sum (CUSUM) method	Postoperative up to 2 years throughout study recruitment

Collaborators and Investigators

• Sponsor: Changi General Hospital
• Investigators: Principal Investigator: Chi Wei Mok, Changi General Hospital

Study record dates

Study Major Dates

• Study Start (Actual): November 24, 2022
• Primary Completion (Actual): December 31, 2023
• Study Completion (Actual): March 1, 2024

Study Registration Dates

• First Submitted: March 4, 2024
• First Submitted That Met QC Criteria: March 21, 2024
• First Posted (Actual): March 28, 2024

Study Record Updates

• Last Update Posted (Actual): March 28, 2024
• Last Update Submitted That Met QC Criteria: March 21, 2024
• Last Verified: March 1, 2024

More Information

Terms related to this study

• Keywords: Breast cancer; Minimally invasive breast surgery; endoscopic breast surgery; robotic breast surgery
• Additional Relevant MeSH Terms: Skin Diseases; Neoplasms; Neoplasms by Site; Breast Diseases; Breast Neoplasms
• Other Study ID Numbers: 2021/2680

Drug and device information, study documents

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