Proton Therapy for Breast Cancer

Cancers Treated: Breast Tumors

Breast Cancer

Breast cancer is the second deadliest cancer among women in the United States, but treatment breakthroughs, like proton therapy, are increasing the odds for survival.

Why proton therapy

Proton therapy limits radiation exposure to healthy surrounding tissue in two ways. First it focuses the highest radiation dose to the tumor. Also, the proton beam can conform to the shape, depth, and size of the tumor. This is especially important when you consider the proximity of the heart and lungs to the breasts.

Sometimes traditional radiation, using X-ray technology, is adequate to avoid the heart during breast cancer treatment, but not always. The heart is close to the left breast in most women, but sometimes the right breast can overlap with the heart, such as when treating lymph nodes close to the sternum (internal mammary nodes). Even motion tricks, like taking a deep breath and holding it, during X-ray beam therapy, aren’t always enough to spare cardiac tissue.

We know that cardiac sparing is important because after treatment, breast cancer patients are at increased risk of developing cardiac side effects like a heart attack or needing a stent in a cardiac artery. Even cardiac death, albeit rare, is a known risk. The main artery to the heart, the LAD (Left anterior descending) is especially close to the left breast, often less than an inch away. Traditional X-ray treatment can move the radiation dose away from the LAD, but sometimes this means pushing more of the X-ray dose into the lungs, opposite breast, or other parts of the heart. Proton therapy has been shown to reduce radiation doses to the LAD as compared to X-rays.

Other Proton Therapy Benefits

  • May reduce radiation doses to the lungs.
  • Typically has less impact on quality of life both during and after treatment.
  • Can be used to treat previously irradiated areas.

Proton therapy is fundamentally different from X-ray therapy, because the proton particles can stop at a set distance, before going deeper into the heart. X-ray beams don’t stop, and travel through the body.

Proton Therapy Candidates Typically Have:

  • Stage I, II, or III breast cancer.
  • Breast cancer in the lymph nodes.
  • Breast cancer that has spread locally.

You can learn more about whether you are a candidate for proton therapy by getting a doctor’s referral to McLaren Proton Therapy Center or by setting up a consultation on your own. To get the process started, call 1-855-My Proton or 1-855-697-7686.

If You Are a Candidate

Before your first treatment, you will have a CT simulation. This is an imaging process used to map out the location, shape, and size of your tumor. The number of treatments and duration of each session will vary based on your specific case.

Breast Cancer Facts
(From the American Cancer Society)

  • Both women and men can get breast cancer.
  • One in eight women will be diagnosed with breast cancer in her lifetime, making it the most common cancer in Women.
  • The American Cancer Society estimates nearly 300,000 new breast cancer cases in the United States this year, and nearly 44,000 deaths.
  • Early detection through regular screenings, like mammograms and self-exams, is key to combatting breast cancer.

Request a Referral or Information Today Schedule An Appointment - (855) 697-7686

Learn More About Treatment of Breast Cancer

There are different treatment types for patients with breast cancer including surgery, radiation therapy, chemotherapy, hormone therapy, targeted therapy and immunotherapy. New treatments are also being tested in clinical trials

Information from the National Cancer Institute


Information about breast cancer, causes, risk factors, diagnosis and treatment.

Learn More: NCI