Im 5 years post radiation. When they do the mapping the appropriate ammount is targeted and hence why they take a while to measure you if you havent had this yet make sure you take panadol or nuerofen on the day of measurement as tour back will ache. If your treatment is on your heart side they measure to protect it. My soreness is still there and takes many years to go in dome people. But my onco told me recently the benefits go on for a long time. You may be lucky to recieve the new treatment of 1 go with a baloon insertion do ask its very new. Adean xx