Our 24/7 cancer helpline provides information and answers for people dealing with cancer. We can connect you with trained cancer information specialists who will answer questions about a cancer diagnosis and provide guidance and a compassionate ear.
Our highly trained specialists are available 24/7 via phone and on weekdays can assist through video calls and online chat. We connect patients, caregivers, and family members with essential services and resources at every step of their cancer journey. Ask us how you can get involved and support the fight against cancer. Some of the topics we can assist with include:
For medical questions, we encourage you to review our information with your doctor.
Radiation therapy uses high-energy rays (or particles) to kill cancer cells or slow their rate of growth. The goal of radiation therapy may change based on the situation.
For some cancers that have not spread too far from where they started, it can be used alone or with other treatments such as surgery with the goal of trying to cure the cancer.
When cancer has spread extensively, radiation can be used to relieve symptoms such as pain, bleeding, trouble swallowing, intestinal blockage, compression of blood vessels or nerves by tumors, and problems caused by metastases to bones.
Internal radiation therapy lets your doctor give a dose of radiation to a smaller area and in a shorter time than is possible with external radiation treatment.
Sometimes, both internal and external beam radiation therapies are used together.
Depending on where the radiation is aimed or placed and what dose is given, side effects may include the following:
Possible general side effects from radiation
Possible side effects from radiation to the head and neck
Radiation therapy to the head and neck area often causes damage to the throat and salivary glands, which can result in:
Over the long term it can also lead to cavities in the teeth and thyroid problems (from damage to the thyroid gland). This might mean that you need pills to replace thyroid hormone.
Possible side effects from radiation to the chest
Possible side effects from radiation to the abdomen
Possible side effects from radiation to the pelvis
Most of these side effects go away after treatment ends, but some are long-term and may never go away completely.
If chemotherapy is given along with radiation, the side effects are often worse.
There are ways to relieve many of these side effects, so it’s important to discuss any changes you notice with your cancer care team.
Our team is made up of doctors and oncology certified nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.
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Last Revised: March 9, 2018
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