Why does my mother need treatment planning for radiation therapy for lung cancer?

1 answer | Last updated: Feb 02, 2011
A fellow caregiver asked...

My mother has a stage III tumor in her lung and her doctor has recommended radiation treatment, but he's scheduling a radiation planning appointment first. Why can't we just start the radiation immediately?

Expert Answers

Oncologist Shalom Kalnicki is chairman of radiation oncology at Montefiore Medical Center and the Albert Einstein College of Medicine, New York.

Many radiation therapy centers now offer advanced technologies that use a variety of computer imaging techniques to image, or "map," the tumor before therapy begins. Scans such as MRIs and CTs capture images of the tumor so the radiation specialists can measure it in three dimensions and determine exactly where the cancerous tissue stops and healthy tissue begins. Then advanced computer software calculates the exact size, shape, and depth of the tumor.

This computerized treatment planning allows your parent's doctors to set up the radiation therapy in terms of the size, number, directions, and angles of thousands of tiny beams to more accurately target the tumor while sparing normal tissue. The result of all these measurements and calculations is that the beams can be distributed around the tumor exactly the way you want them to be, avoiding damage to healthy or healing tissue.

Frequently, doctors use PET scans to determine if parts of the tumor are more or less biologically active. Then higher-dose beams of radiation can be used on the more active portions, instead of giving the same dose across the whole tumor.

It's understandable that you're impatient to begin your parent's treatment, but studies show that advanced radiation techniques and treatment planning give much better results than conventional radiation treatment, so it's worth taking the time to get it right.