- Question from RavenW: Why must radiations be given so close together if it causes so much skin irritation? Wouldn't it be better to space it out some?
Lydia Komarnicky, M.D.
We know that radiation given daily five days per week over six to seven weeks works best. Spacing it out or skipping days is not the best way to deliver radiation.
We know that from giving radiation daily, the risk of recurrence in the breast is low. So most radiation oncologists are not willing to change that pattern, because we know it works.
Marisa Weiss, M.D.
Radiation works best when one dose builds on the next dose. In between doses, normal tissue is better able to repair the effects of radiation, because they have their 'act together' better, whereas cancer cells grow in a more erratic and uncontrolled way. They're not as good at repairing radiation damage in between treatments.
So when one treatment is given close to the next treatment, the damage adds up more in the cancer cells and you're more likely to kill those cancer cells.
- Lydia Komarnicky, M.D. From historical studies looking at radiation biology—the effect of radiation on cells—we know that giving daily doses of radiation works best, as opposed to one dose a week or two doses a week. You need to give daily radiation for at least five days.
- Marisa Weiss, M.D. If you have a four-day week because of a holiday or another important reason, don't worry. Your treatment is still effective when the rest of the weeks of treatment are given in a more continuous fashion.
- Lydia Komarnicky, M.D. An occasional interruption would be OK. Continued interruptions on a weekly basis would not be recommended. You can make up an occasional interruption at the end.
On Wednesday, March 17, 2004, our Ask-the-Expert Online Conference was called Radiation Therapy Updates. Lydia T. Komarnicky, M.D. and Marisa Weiss, M.D. answered your questions about advances in radiation therapy: the newest and best techniques, combining radiation therapy with other treatments, ways to manage, reduce or eliminate side effects, and more.
The materials presented in these conferences do not necessarily reflect the views of Breastcancer.org. A qualified healthcare professional should be consulted before using any therapeutic product or regimen discussed. All readers should verify all information and data before employing any therapies described here.
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