In a world-first, scientists have developed a breakthrough treatment that uses light to kill cancer cells.

We often think of light as a life-giving source, but in the case of photoimmunotherapy — the use of light to help a person’s own immune system fight cancer — light can both be a source of life, for the patient, and death, to cancer cells.

A multidisciplinary team of European scientists joined forces to design the new treatment, which works by combining a special fluorescent dye with a cancer-targeting compound.

Shining light on the compound forces cancer cells to glow in the dark, helping surgeons to remove more of the tumors compared with existing techniques.

Then, the surgeon would shine near-infrared light on the site, switching the compound into tumor-killing mode and killing off any remaining cells.

The trial of this therapy was done on mice with a particularly aggressive form of brain cancer called glioblastoma.

Findings showed that the mice had clear signs of tumor death in as little as one hour after exposure to the light. The treatment also triggered an immune response that could mount a new attack on cancer should it come back.

Study leader Dr. Gabriella Kramer-Marek told The Guardian, “Brain cancers like glioblastoma can be hard to treat, and sadly, there are too few treatment options for patients. Surgery is challenging due to the location of the tumors, and so new ways to see tumor cells to be removed during surgery and to treat residual cancer cells that remain afterward could be of great benefit.”

Scientists are quite hopeful that the results will be duplicated when they study the treatment of humans. In the meantime, this trial has shined a light at the end of a long, dark tunnel.

By Natasha Gutshtein