I'm a Radiation Oncologist and just wanted to speak a little bit to discussion regarding breast cancer treatment and impact to the heart and lung. Modern radiation therapy planning and delivery techniques do a great job protecting your underlying organs from radiation exposure. Heart sparing is something we take great care in doing and utilize several techniques for it. You may be treated prone (on your belly with treated breast handing down), or asked to use deep inspiration breath hold technique (DIBH) or we sometimes utilize proton beam therapy. Prone positioning is good when you are only needing to treat breast tissue (no nodes) and the breast tissue readily pulls away from the chestwall when you're facedown. DIBH is a way of cheating your anatomy to protect your organs - when you take in a deep breath the lungs double in size which pushes the heart back from the chestwall as well as making the total amount of lung that gets some of the low dose behing the breast much less. But for some cases, particularly those in which we need to treat lymph node areas, even DIBH doesn't protect the lungs as much as we'd like to keep your risk of pneumonitis low. In those cases, proton beam therapy (charge particle therapy) can be a benefit. Because of the charge on the particles, the exit dose is eliminated and you almost completely spare tissue outside of the breast and lymph node areas. However, proton beam therapy has limited availability and insurance coverage is highly variable.

Best wishes with your radiation therapy! It will be done before you know it!