Proton Therapy vs. Conventional Radiation Therapy: What to Know

May 05, 2022
Radiation therapy is a common technique for targeting cancerous tumors. But what’s the difference between conventional radiation therapy and the newer proton therapy?
“It’s important to note that proton therapy is a type of radiation therapy that targets tumors,” says Nicholas DeNunzio, M.D., Ph.D., a radiation oncologist at Hackensack Meridian John Theurer Cancer Center who is fellowship trained in proton therapy.
Dr. DeNunzio describes the biggest differences in the two approaches:
- With conventional radiation therapy, X-rays can be deflected on their way to the target and are not cleanly absorbed at the directed site, such that the dose is delivered to areas that don’t need it. In contrast, protons enter the body, deliver less dose on their way to the target and release most of their energy when reaching their destination. This limits the dose to surrounding tissues.
- With conventional radiation therapy, some particles scatter to nearby tissues after reaching their target. With proton therapy, the protons stop once they reach the tumor, so there is no exit dose.
“The combination of these attributes makes proton therapy highly targeted in killing a tumor,” Dr. DeNunzio says.
Who is a Candidate for Proton Therapy?
Proton therapy can be used to effectively treat most tumors. “That said, every clinical scenario is unique,” says Dr. DeNunzio. “Whether proton therapy may benefit a given patient is best determined by a radiation oncologist trained to deliver this specialized therapy.”
Generally speaking, proton therapy may be an option for patients with these types of tumors/cancers:
- Brain tumors
- Breast cancers
- Esophageal cancers
- Head and neck tumors
- Lung tumors
- Lymphomas
- Pediatric cancers
- Prostate cancer
- Skull-based tumors
- Testicular cancers
- Tumors near the spine
What to Expect from Proton Therapy
The proton therapy process is very similar to conventional radiation therapy. “With both, we’ll start with a consultation and then a planning session,” Dr. DeNunzio says. “Patient treatment times are generally similar—about 20–30 minutes per appointment.”
Both types of therapy are painless during treatment and similar in the types of side effects that may arise. However, proton therapy can often reduce the chance of these side effects from developing during treatment or in the months or years following.
“Many people are living more years after cancer treatment,” Dr. DeNunzio says. “Trying to mitigate the long-term impact of cancer therapy is incredibly important—we are not just thinking about what we are trying to do now, but five, 10, even 20 or more years down the line.”
Next Steps & Resources:
- Meet our source: Nicholas DeNunzio, M.D., Ph.D.
- To make an appointment with Dr. DeNunzio or to find a radiation oncologist near you, call 800-822-8905 or visit our website.
- Learn more about proton therapy at John Theurer Cancer Center, delivered in conjunction with ProCure NJ
The material provided through HealthU is intended to be used as general information only and should not replace the advice of your physician. Always consult your physician for individual care.
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