Endoscopic Detection of Fluorescein for Sentinel Lymph Node Biopsy

DESCRIPTION (provided by applicant): The objective of this grant is to develop fluorescence endoscopy instrumentation to facilitate the surgical management of breast cancer, with possible application to other types of cancer. The specific aims for this project are to develop a combination holographic notch filter adapter and switchable high-intensity LED light source adapter for currently available surgical telescopes. This new device will allow the surgeon to perform the axillary dissection of lymph nodes in breast cancer patients with minimally-invasive surgical techniques. This new device will be a more efficient, more accurate, more cost-effective and safer way to perform the sentinel lymph node dissection of lymph node clusters in breast cancer patients. Illumination of a fluorescent lymphatic mapping agent with an appropriately matched fluorescent light source will be more efficient as red- shifted red and near-infrared fluorescent light is visible through many layers of tissue. This may reduce operating room time and obviate the need for a complete axillary dissection which is needed with the currently used visible dye marker (Lymphazurin(r). This device will be more accurate than the gamma ray detector used to find the radioactive marker (technetium sulfur colloid). Fluorescence endoscopy will be less-expensive per patient, as it replaces two imaging agent drugs (one of which is radioactive). Vestan will produce several prototype holographic optical notch filters and switchable high-intensity LED light sources that are matched to the FDA- approved fluorescent drug, fluorescein. The optical notch filter will attach directly to currently used surgical telescopes for the convenience of the operators. Fluorescein is available to all surgeons and it is currently used to determine intraoperative bowel viability. Vestan will demonstrate the feasibility of the device in a pig model of lymphatic mapping. Fluorescein will be injected into the dermis of the hind limb of adult pigs. The fluorescence endoscopy instrumentation will be used to define the lymphatic vessels and to find the sentinel lymph node with minimally-invasive surgical techniques. The accuracy of the device will be evaluated against the currently used blue dye, Lymphazurin(r). Since 200,000 new cases of breast cancer occur each year, and all require an axillary lymph node dissection, this new approach will benefit thousands of women, using three % inch incisions to replace an 8 inch incision. In addition, this new method of finding the sentinel lymph node with fluorescence avoids the use of radioactive drugs and the use of a dye that is associated with a 1% risk of anaphylactic shock.