Radiation therapy uses high-energy beams to treat cancer. These beams kill tumor cells by damaging the DNA and destroying the cells. Advances in radiation therapy, including more detailed imaging techniques, improved delivery systems, and a better understanding of genes and the immune system, have improved patient outcomes.

Advances in imaging

Better technology enables radiation oncologists to more accurately define the tumor, its size, and location so that the radiation is given just to the tumor and sparing, as much as possible, the normal tissues that surrounds it. One such method is stereotactic guidance, which uses 3-D imaging data, including computed tomography (CT) or magnetic resonance imaging (MRI)).

Radiation oncologists can also combine live streaming video imaging (4-D imaging) along with normal imaging guidance to correct for movements such as breathing during treatment.

“By finding genetic mutations, we can now better predict which patients will respond to what therapies and who will benefit most from combination therapy...”

Reducing unwanted effects

Stereotactic body radiotherapy has improved patient outcomes by using multiple radiation beams from different angles that hit the tumor from all sides. By using CT or MRI imaging during treatment, also known as image-guided, intensity-modulated radiation therapy, radiation oncologists may now take images of the tumor and surrounding area to make sure that the patient is positioned exactly as they should be.

The result is the ability to deliver very high radiation doses to the tumor while the non-cancerous tissues around the tumor get minimal to no radiation dose. This results in fewer side effects for patients.

Genomic approaches

Knowing the genetic sequence of a patient or their tumor helps improve patient outcomes. By finding genetic mutations, we can now better predict which patients will respond to what therapies and who will benefit most from combination therapy such as radiation plus chemotherapy.

Our improved understanding of how the immune system can be used to fight cancer helps us develop better approaches to killing cancer cells. New immunotherapy treatments have helped to create more cancer survivors, but early data indicates that combining immunotherapy and radiation therapy may offer a better solution, and can potentially cure some patients with metastatic disease that has spread to other areas of the body.

Radiation therapy has advanced significantly in the past 20 years. This improved efficacy and reduced toxicity has resulted in better patient outcomes resulting in more cancer survivors. As we progress into an era of highly personalized cancer treatment, these advances must reach across fields, bringing together the best ideas from radiation oncology, medical oncology and surgical oncology, to create even more optimistic futures for individuals diagnosed with cancer.