Between 20 and 50 percent of human cancer patients will experience a local recurrence due to malignant cells left behind after tumor removal surgery. Surgeons (for both animals and humans) typically rely on sight and touch, which can be difficult.
Now researchers at the University of Pennsylvania have made progress on a technique that will increase successful tumor removals and decrease the likelihood of recurrence.
The collaboration between the veterinary and medical school explored using an injectable dye (indocyanine green or ICG) that accumulates in cancerous tissues more than normal tissues. This concentration occurs because the blood vessels of tumors have “leaky walls” from growing so rapidly. When a near-infrared light (NIR imaging) is shined, the tumor glows making removal easier.
The technique was first tested on mice, and then on eight dogs and five people at the University's hospitals. The surgeries were successful in making the process easier. In one of the human patients, NIR imaging revealed glowing areas that were thought to be healthy areas of the lung. The patient went on to receive chemotherapy and survived, thanks in large part to the new technique.
So far the limiting factor has been that ICG also absorbs into inflamed tissue, which can complicate its use. To avoid this problem, the researchers are working to identify an alternative targeted contrast agent specific to a tumor cell marker.
Glowing tumors are very impressive, but it's even cooler to see animal and human medicine come together to develop mutually beneficial advancements!