Gabrielle Gauvin

Background:

Gabrielle completed her Bachelor of Science with Honors in Biopharmaceutical Science as well as her medical degree at the University of Ottawa. She is currently in her 3rd year of General Surgery residency at Queen’s University. Along with clinical research, she also has a great interest in medical education and is involved in several education committees. She developed a surgery orientation handout for medical students and junior residents. She also started a sustainable program to involve the residents in the surgical clerks’ orientation process. She presented her work at the Canadian Undergraduate Surgical Education Committee (CUSEC) podium session of the Canadian Surgery Forum (Vancouver, 2014): “Starting the day off right: residents’ role in orienting surgical clerks”. Following residency, Gabrielle plans to pursue a clinical fellowship in Surgical Oncology.

Research Summary:

Breast-conserving surgery using real-time electromagnetic navigation

Breast cancer is treated during its early stages with breast-conserving surgery. Accurate delineation of the tumor margin is difficult as most lesions are not palpable, and breast tissue deforms during surgery. Current strategies, including gold-standard wire-localization, have positive margin rates as high as 47%. We propose using real-time electromagnetic (EM) tracking to three-dimensionally delineate and track the tumor resection volume, allowing the surgeon to navigate around the tumor and improve the precision of the resection. The EM navigation system utilizes an ultrasound (US) to register the tumour resection volume from a tracked needle fixed in the tumor, allowing tumor movement to be followed in real-time during surgery. This method has the potential to reduce the incidence of positive margins, while reducing the amount of healthy tissue removed.

We first performed a study using PVC phantom breast models created to simulate breast tissue density and deformability. We saw a reduction in the positive margin rate from 42.9% in the control group to 19.0% in the EM navigation group. A second study was done on cadavers to improve the workflow on real breast tissue. A clinical feasibility study is being conducted on patients with a palpable tumor to test the ease of use of EM navigation in the operating room setting. This study currently shows no EM-specific complications or breach in sterility. Feedback questionnaires state that none of the participants find that the EM sensors interfere with the surgical procedure, and that the EM navigation is easy to use.

These studies have led to presentations in Canada: Canadian Surgery Forum (Vancouver, 2014); USA: American Miami Breast Cancer Conference (Miami, 2015), Image Guided Therapy Workshop (Cambridge, 2014); International: Computer Assisted Radiology and Surgery (Barcelona, 2015), Hamlyn Symposium on Medical Robotics (London, 2014). The poster “Real-Time Electromagnetic Navigation for Breast Tumor Resection: Proof of Concept” presented at the Canadian Surgery Forum (Vancouver, 2014) wonthe best poster award for the Canadian Society of Surgical Oncology category.

Queen’s Department of Surgery Development and Innovation Fund internal department grant was awarded to co-fund the palpable tumor study. An Academic Health Science Center (AHSC) Alternate Funding Plan (AFP) Innovation grant was recently awarded by the Southeastern Ontario Academic Medical Organization (SEAMO) to fund the next phase of this project, a clinical trial to see if EM navigation reduces the rate of positive margins in breast-conserving surgery for non-palpable tumors.

As a plug, if you are interested in participating the next step: multi-center RTC, please contact CJay.Engel@krcc.on.ca.