Radiation Therapy for Salivary Gland Cancer

3D-CRT uses special computers to precisely map the location of the tumor. Several radiation beams are then shaped and aimed at the tumor from different directions.

Each beam alone is fairly weak, which makes it less likely to damage the normal tissues, but the beams join together at the tumor to give a higher dose of radiation there.

IMRT is an advanced form of 3D-CRT. Along with shaping the beams and aiming them at the tumor from several angles, the intensity of the beams is adjusted to limit the dose reaching the most sensitive nearby normal tissues.

This lets the doctor give a higher dose to the tumor. Many major hospitals and cancer centers now use IMRT, and it is often the preferred method for salivary gland tumors.

Proton beam therapy focuses proton beams on the tumor. Unlike x-rays, which release energy both before and after they hit their target, protons cause little damage to the tissues they pass through and then release their energy after traveling a certain distance. This means more radiation can be delivered to the tumor while doing less damage to the normal tissue around it.  

Like proton beam radiation, this method limits radiation exposure to healthy tissues and focuses radiation energy on the tumor. This method is only available in a few centers in the world.

Fast neutron beam radiation uses a beam of high-energy neutrons instead of using x-rays. Neutrons are neutral particles in atoms. Some studies have suggested that this type of radiation might be more effective, but it might also lead to more side effects. Neutron therapy might not be available in all treatment centers.

Many people treated with radiation to the salivary gland area have painful sores in the mouth and throat that can make it very hard to eat and drink. This can lead to weight loss and poor nutrition.

The sores heal with time after the radiation ends, but some people continue to have problems swallowing long after treatment ends because of the tightening of the muscles caused by radiation.

Ask your speech pathologist about swallowing exercises you can do to help keep those muscles working and increase your chance of eating normally after treatment. Liquid feeding through a tube placed into the stomach might be needed.

Damage to the salivary (spit) glands from radiation can cause a dry mouth that doesn't get better with time.

For most major salivary gland cancers, radiation is only given to the side of the face and neck with the cancer, which reduces the risk of serious long-term side effects.

In rare instances, both sides of the face and neck might need to be treated with radiation. This might damage other salivary glands, resulting in permanent dry mouth. This can lead to discomfort and problems eating and swallowing, as well as damage to the jawbone.

The lack of saliva can also lead to tooth decay (cavities). People treated with radiation to the mouth or neck need to practice careful oral hygiene to help prevent this problem and see their dentist regularly. Fluoride treatments might also help.

This problem, known as osteoradionecrosis of the jaw, can be a serious side effect of radiation treatment. This is more common after tooth infection, extraction, or trauma, and it can be hard to treat.

The main symptom is pain in the jaw. In some cases, the bone actually breaks. Sometimes the fractured bone heals by itself, but often the damaged bone will have to be repaired with surgery.

To help prevent this problem, people getting radiation to the mouth or throat area need to see a dentist to have any problems with their teeth treated before radiation is started. In some cases, teeth might need to be removed.

Lockjaw, also known as trismus, is a condition in which the mouth cannot open fully. This can be a serious side effect of radiation treatment.

It happens because of scarring or damage to the muscles, joints, and tissue that help the jaw work. This can make it hard for people to chew their food well, speak clearly, and can increase the chance of cavities.

Not everyone who gets radiation for salivary gland cancer will have this side effect, but spotting the problem early can help people start treatment sooner and lower the chances that it will cause major troubles.

The nerves or organs that help you hear can be damaged by radiation. You might be asked to see an audiologist, a person who specializes in hearing, to test your hearing before and after treatment to watch for signs of hearing loss.

Radiation might damage your thyroid gland. Your doctor will do blood tests regularly to see how well your thyroid is working. Some people might need to take pills to replace thyroid hormones at some point if the thyroid gland is not working well.

Some people treated with radiation therapy might be at risk of developing lymphedema swelling in the head and neck areas that were treated. These areas can become enlarged, firm, and painful. This can be worse if the person also had surgery. Sometimes, medicines, physical therapy, or massage therapy might be helpful.

Radiation to the neck area might increase a person’s risk of stroke many years after treatment. This might be because of damage to the blood vessels or health problems that were already present before radiation such as narrowing of the artery from plaque, both of which can decrease blood flow.

Smoking cigarettes also damages the arteries. Because of this, some doctors might order regular ultrasounds after treatment to watch the blood flow to the brain.