Side effects can occur with any type of treatment for parathyroid cancer, but not everyone has them or experiences them in the same way. Side effects of radiation therapy will depend mainly on the:
Radiation therapy damages cancer cells, but healthy cells in the treatment area can also be damaged, even though steps are taken to protect them as much as possible. Different cells and tissues in the body tolerate radiation differently.
Side effects can happen any time during, immediately after or a few days or weeks after radiation therapy. Most side effects go away after radiation therapy is finished. Late side effects can occur months or years after radiation therapy. Some side effects may last a long time or be permanent.
It is important to report side effects to the healthcare team. Many side effects can be relieved by medications, a change in diet or other measures. Doctors may also grade (measure) how severe certain side effects are. Sometimes radiation therapy treatments need to be adjusted if side effects are severe.
Fatigue is one of the most common side effects of radiation therapy. Fatigue may be caused by anemia, poor appetite or depression. It may also be related to toxic substances that are produced when cancer cells break down and die. During radiation therapy, the body uses more energy to heal itself, so fatigue will not always be relieved by rest. Making frequent, daily trips for radiation treatments can also be tiring.
Radiation therapy to any area of the body can make a person feel more tired than usual, but is more common when larger areas of the body are treated. Anemia is more likely to occur when the treatment area includes areas where blood cells are formed in the bone marrow, such as the pelvic bones.
Fatigue usually occurs during the second week of radiation treatment or later. Symptoms of fatigue may increase or become more severe over the course of treatment. Fatigue usually goes away gradually after treatment has ended, but some people continue to feel tired for several weeks or months after radiation therapy is finished.
Skin reactions occur because external beam radiation travels through the skin to reach the area being targeted for treatment. The skin in the radiated area may become red, dry or itchy, or it may change colour (become darker or tanned looking). Most skin reactions occur within the first 2 weeks of receiving radiation treatment. They usually go away a few weeks after treatment, but some skin changes, like skin darkening or scarring, can be permanent. Some people do not experience any skin reactions with radiation therapy.
Nausea and vomiting are not common side effects of radiation therapy for parathyroid cancer, but they can occur. Nausea and vomiting may occur after the first or second week of radiation therapy. They can usually be managed with anti-nausea medication and usually go away after treatment is finished.
Diarrhea is frequent and very loose (watery) stools. Abdominal cramping may occur with the diarrhea. Diarrhea often begins 2–3 weeks into radiation therapy. Report diarrhea to the radiation therapy team. They can suggest over-the-counter or prescription medicines to help relieve diarrhea.
Radiation to the neck can cause hypothyroidism (a decrease in thyroid function). The thyroid makes hormones that help regulate and maintain many body functions. Symptoms of hypothyroidism include fatigue, hair loss, brittle nails, dry skin or changes in menstruation in women.
Hypothyroidism usually develops 3–4 years after treatment, but can also occur several years later.
Thyroid function is checked and daily medications (thyroid hormone replacement) may be needed to regulate the thyroid.