Removing all cancerous tissue during surgery, and obtaining clear margins—the area of tissue that is free of cancerous cells—is critically important, but it is not always easy or possible.
As archaic as it sounds, a surgeon has no way of knowing precisely where cancerous tissue ends and the margin of healthy tissue begins. Often, when post-surgery pathology shows that cancer cells remain, cancer patients, including those with breast cancer who undergo lumpectomy or mastectomy, need another visit to the operating room to eradicate rogue tissue that may otherwise escape a surgeon’s visual examination. According to Dr. Jim Olson, a pediatric oncologist at Fred Hutchinson Cancer Center who cares for children with brain cancer, “Thirty percent of women who have breast cancer find out that where the surgeon stopped cutting, there are still cancer cells, and that they probably need to have more surgery done. And unfortunately, they get this information 7 to 10 days after they’re out of the operating room.”
Inspired by many of his young patients, Dr. Olson and his creative research team developed Tumor Paint to identify cancerous tissue during surgery so that it can be removed during the initial operation. Simple and effective, injectable Tumor Paint is derived from a peptide in scorpion venom that naturally binds to brain cancer cells. Combining it with a fluorescent molecule that “lights up” cancerous cells and bypasses healthy cells, surgeons can more easily distinguish normal tissue from tissue that needs to be removed and that might otherwise go undetected. (After a tumor is removed, the surgeon uses a special near-infrared camera to make sure no stray cancerous cells have been left behind.)
Initially developed to save healthy brain tissue, in preclinical trials involving animals, Tumor Paint has successfully illuminated prostate, colon, breast and other cancers. If human clinical trials next year are successful, Tumor Paint will become perhaps the most important surgical tool for reducing repeat surgeries, limiting or elminating the amount of normal tissue that is removed, and ultimately, saving lives.
To learn how Dr. Olson was inspired by individual patients that he cared for, and how this inspiration led to a whole new platform of potential cancer drugs that come from violets, sunflowers, spiders, scorpions and other nature-based sources, watch his recent TEDxSeattle talk. To encourage those who care about breast cancer to spread the word, the Washington Research Foundation (WRF) has offered to donate up to $50,000 ($10 for each view).