Intraoperative Breast Cancer Tumor Margin Assessment Using NIR Quantum Dot Molecular Probes
Tuesday, March 15, 2022
10:45 AM-12:45 PM
BIOMED PhD Research Proposal
Title:
Intraoperative Breast Cancer Tumor Margin Assessment Using Near Infrared (NIR) Quantum Dot Molecular Probes
Speaker:
Alexandra Jednorski, PhD Candidate
School of Biomedical Engineering, Science and Health Systems
Drexel University
Advisors:
Wan Y. Shih, PhD
Professor
School of Biomedical Engineering, Science and Health Systems
Drexel University
Wei-Heng Shih, PhD
Professor
Department of Materials Science and Engineering
College of Engineering
Drexel University
Abstract:
About 1 out of 8 women in the US will develop breast cancer in her lifetime. Most breast cancer patients undergo a lumpectomy surgery to excise the tumor specimen. About 25% of the time the margins of the tumor are determined, post-operatively, to be positive, meaning there was cancer left in the patient. The patient must then undergo another surgery, called a re-excision surgery to remove the cancerous area that was left behind. Current methods of assessing tumor margins during the first operation (intraoperatively) lack sensitivity and specificity in detection of the cancerous areas, are prone to error, or do not work with all tumor types, such as very large or small and dense or fibrous lesions. Most of the current methods also require the expertise of a pathologist to perform and interpret hematoxylin and eosin (H&E) staining of the tissues. The pathologist is not always available to perform these procedures. Therefore, there is a need for a highly specific and quantitative intraoperative breast cancer margin assessment technique that can work for any excised specimen without the need for a pathologist.
The goal of our work is to develop an intraoperative breast cancer margin assessment tool using a breast cancer-specific antibody-near infrared quantum dot (NIR QD) molecular probe. The fluorescent probe uses QDs, which are superior to traditional organic dyes in their brightness and photostability. The CdPbS QDs used in this work have a near infrared emission, emitting light above any autofluorescence from biological tissues. Therefore, there is no background during tissue imaging. The QDs will be conjugated to an antibody (Ab) to target the Tn antigen, specific to carcinomas. Each molecular probe will have multiple QDs per Ab, making the staining as bright as possible. A spacer arm will be implemented to allow multiple QDs per Ab without blocking the binding site of the Ab and rendering the probe useless. Because the QDs are conjugated to a primary Ab, the excised tumor tissue can be stained directly with the probe. This will drastically cut down the time needed for staining and the time the patient must be under anesthesia. The probe’s fluorescent signal can be easily imaged and margin assessment determined using a custom imaging setup. While this specific tool is targeted for breast cancer tumor margin assessment, it can be applied to other diseases with distinct antigens.
Contact Information
Natalia Broz
njb33@drexel.edu