Survivorship: Late Effects After Radiation Treatment for Thyroid Cancer.

Side Effects After Cancer Treatment

There are different types of side effects you may have during or after cancer treatment.

• Short-term: side effects that happen while you are on treatment and end shortly after.
• Long-term: side effects that happen while you are on treatment and last for months to years. Some of these side effects will not go away. Example: neuropathy.
• Late effects: side effects that happen months to years after you have finished treatment. Example: scar tissue forming and causing health issues.

This article focuses on the late effects of radiation treatment for thyroid cancer.

Late effects can be health issues or psychological, emotional, and practical challenges.

Late Effects After Radiation for Thyroid Cancer

Side effects from radiation treatment affect the area of the body in the treatment field. The treatment field includes the cancer and in some cases nearby healthy tissue. How radiation is given has changed over the years, leading to a lower risk of late effects. Talk with your radiation oncologist to find out which areas were in your treatment field.

Late effects of radiation treatment for thyroid cancer include:

Oral Health

Radiation to the head and neck can harm the salivary (parotid) glands. This can lead to changes in how your saliva is made and can lead to dry mouth or thickened saliva. This can be a side effect that is short-term (gets better after treatment) or long-term (lasts a long time, even forever). Loss of saliva can make it hard to eat and speak.

• Saliva kills bacteria in your mouth and on your teeth. Without saliva, you are at risk of tooth decay (cavities). Taking good care of your teeth and gums is important. You should brush your teeth twice a day and floss daily.
• Visit your dentist for cleanings and oral exams every 6 months. Fluoride treatments can help prevent cavities and decay. Your dentist and oncology team will help you decide what fluoride treatment is best for you.
• Tips to help with changes to your saliva production are:
  • Use saliva substitutes. These come in gels, lozenges, and sprays. They are available by prescription or over the counter. Your provider can give you suggestions for these products.
  • Chew on sugarless gum or suck on sugarless candy. This can help stimulate saliva production.
  • Drink plenty of water; keep a water bottle on hand.
  • Suck on ice chips.
  • Avoid soda, caffeinated beverages, alcohol, and tobacco.
  • Avoid sugary foods, candy, and drinks.
  • Eat moist foods and sip liquids with your meals.
• Changes in, or a loss of taste or smell can happen during treatment and can be permanent (won’t go away). You could also have a hard time chewing or swallowing.

Ask your care team about seeing a Registered Dietitian if you are having trouble eating because of dry mouth, decreased taste/smell, or trouble chewing or swallowing.

Skin Changes

Radiation can lead to changes in the skin that don’t go away.

• You may find new scars or notice changes in the color or texture of your skin. Radiation can also change the color and texture of your hair or can cause hair loss in the treated area. Your hair might never grow back.
• The soft tissue and muscles under the skin can develop scarring and/or shrinkage, which can lead to a loss of flexibility and movement or chronic swelling in the area treated.
• You may get chronic or recurring ulcers of the skin in the area treated. Blood vessels of the skin may become dilated (larger) and more visible, but this is not harmful.
•  If the skin feels tight or sore, you can apply vitamin E.
• Use fragrance and dye-free soaps and moisturizers if your skin is sensitive after radiation.

After radiation, the skin in the treated area is more sensitive to sunlight. This sensitivity will last for your lifetime. Practice sun safety, use plenty of sunscreen, wear a wide-brimmed hat, and keep skin in the treated area covered with clothing. Try not to be out in the sun between the hours of 10 am-4 pm when it is the strongest. If you notice any new or worsening skin issues, you should call your provider for an assessment.

Damage to the Bones

• Radiation can cause small cracks (fractures) in the bones that are in the treatment field. Try to avoid trauma including falls or accidents. If you do get hurt, ask your provider if you need any tests (x-ray) to check for bone damage.
• Radiation to the jaw can cause osteoradionecrosis (ORN) of the jawbone, but this is rare. It causes the jawbone to not be able to heal after minor trauma. It can happen after a dental procedure such as pulling a tooth. It may start as jaw pain or not being able to open the jaw. You should tell you provider about any pain or trouble with opening your mouth. Let your dentist know that you have had radiation to the jaw, so they can watch for ORN.

Throat and Swallowing Problems

Radiation to your upper airway and throat area can lead to scar tissue in the throat. This can happen months to years after treatment.

• This scarring can make your throat narrow, making it hard to swallow, feel like food gets “stuck”, or cause heartburn. If you have these problems, you should be seen by your provider. You may see a gastroenterologist (GI Doctor) or surgeon. They may be able to use a stent or balloon to stretch the scar tissue and widen your throat.
• This scar tissue can also make breathing and speaking hard. Talk with your provider if you are having issues like a hoarse voice or a lasting cough. If you are having severe trouble breathing or are coughing up blood, contact your care team right away or go to an emergency room.

Managing Late Effects 

Tell your care team about any new or worsening symptoms. Some side effects need care from healthcare providers who specialize in working with cancer survivors. There are Interdisciplinary survivorship clinics at many cancer centers. If there is not a survivorship clinic near you, talk with your oncology care team about support for managing your late effects.

After treatment, talk with your oncology team about getting a survivorship care plan, which can help you in your transition to survivorship and learn about life after cancer. You can build your own survivorship care plan using the OncoLife Survivorship Care Plan.