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Radiation Therapy Risks and Potential Side Effects
Radiation therapy itself is painless, and it remains an important treatment tool. But it can cause unwanted symptoms called side effects, either during treatment or afterward — sometimes months or even years later.
Side effects range from mild to severe and depend on the type of radiation, the intensity and the location targeted. Symptoms and intensity also vary between patients.
Thankfully, more precise treatment techniques and doses continue to eliminate or reduce side effects — advances we have taken part in developing and have embraced.
We fully explain potential side effects and incorporate your concerns into our recommendations. If side effects do occur, we track them carefully and can often adjust your treatment. We also provide therapy and full emotional and social support.
Radiation therapy works by damaging the genes of cancer cells so they stop growing and dividing, eventually dying off.
But radiation is a balancing act: providing the most effective treatment possible while still protecting normal cells. Some healthy cells do get caught up in the process, despite doctors’ best efforts to avoid harm. The death of these cells leads to side effects.
Cell death does not occur at equal rates. Fast-growing cells like those in the skin, bone marrow and intestinal lining die quickly, while slow-growing cells like those in the breast, bone tissue and brain might take days, weeks or months. (The same is true for both cancerous and normal cells.)
That means some side effects show up during treatment and end soon afterward, while others take longer to appear.
The types of side effects you may experience are specific to the area of the body that gets treatment. The most common side effects from radiation therapy are skin irritation and fatigue. Your radiation oncologist and nursing team will talk to you in depth about the types of side effects that your treatment may cause.