Conventional radiation for lung cancer damages heart


Note: This is the first in a monthly series of blogs that will be authored by Dr. Ben Wilkinson, radiation oncologist and medical director for Provision Center for Proton Therapy. Dr. Wilkinson will cover a variety of topics related to proton therapy treatment and cancer care.

For some years now, the damage conventional radiation can do to the hearts of breast cancer patients has been documented in the medical literature.

Now, we’re seeing the same effects in lung cancer patients.

In a recent study of 127 patients diagnosed with stage III lung cancer, nearly a quarter suffered from some type of cardiac event an average of 26 months following radiation treatment for their tumors. The report was published in the January issue of the Journal of Clinical Oncology.

Patients suffered from a range of issues including pericardial effusion or fluid collecting around the heart, heart attack, pericarditis, arrhythmia and heart failure. The average follow-up time for patients was 8.8 years.

Radiation is a curative treatment option for many lung cancers that can be combined with surgery or chemotherapy depending on the stage of the patient’s cancer. Conventional radiation treatment typically includes not only lung tumors but also surrounding lymph nodes found in the chest wall. In a typical treatment regimen, a patient receives a radiation dose between 60 to 70 gray. In the recent study published in JCO, average doses as low as 10 to 20 gray were enough to cause unexpectedly high levels of heart damage.

This is one of the first study we’ve seen specifically measuring such results, and, frankly, the degree of the effect of regular radiation on the heart is surprising. While you could easily surmise that conventional radiation would cause some long-term damage to the heart, this study concludes that the effects are felt sooner than we might have expected—and show up in quite a variety of cardiac diseases. This is important data showing that even low doses of radiation make a difference to the long-term health of the heart.

As lung cancer treatments improve, offering longer and improved quality of life to survivors by reducing the amount of radiation that reaches healthy tissues becomes increasingly important.

Unfortunately, with regular X-ray radiation it is difficult to control the surplus dose to surrounding health tissues and organs. Proton beam therapy, on the other hand, offers the advantage of focusing the maximum dose where it is needed, with no “exit dose” beyond the treatment site.

Obviously, each patient is different, but this new data certainly gives us reason to more confidently recommend proton therapy for lung cancers and other thoracic tumors near the heart.