Nearly half of all cancer patients undergo radiation therapy as part of their care. Ionizing radiation, or the emission of high-energy waves or particles, works as a therapy by damaging a cancer cell’s DNA. It’s an effective tool for killing cancer cells because they are generally much less adept at DNA repair compared to healthy cells. Damaging specific parts of DNA prevents cancer cells from reproducing, effectively killing them.
A major limitation of radiation therapy is the damage it may cause as it passes through healthy organs to get to tumors located deep in the body. The need to protect healthy organs limits the dose of radiation that can be delivered to cancerous tissue, thereby reducing the chance of successful treatment.
Overcoming this challenge has long been a mission for medical physicists and radiation oncologists like us. Improvements to radiotherapy will enable clinicians to not only better control tumors overall, but also open the door for more favorable outcomes in patients with cancers that are more resistant to radiation.
Fundamentals of radiation therapy
At the heart of radiation therapy lies the fundamental principle that cancer cells are more susceptible to radiation than healthy cells. However, there are exceptions. Sometimes resistance to radiation in cancer cells may be comparable or even greater than that of their neighboring cells.
