I had the same question when reading this. They use the light only at places where cancerous cells were found plus some safety margin I guess.
In that sense it's an alternative to surgery.
In that sense it's an alternative to surgery.
New modern chemotherapy (anti-body drug conjugates) are also similar to how it "adheres" to cancer cells, by binding to specific cell expression. It's not re-inventing this technology, just finding a new way to leverage it. The drug will also bind to normal cells, but by directing light to a specific area the goal is to minimize damage and side effects.