Hyperthermia (also called thermal therapy or thermotherapy) is a type of cancer treatment in which body tissue is exposed to high temperatures (up to 113°F). Research has shown that high temperatures can damage and kill cancer cells, usually with minimal injury to normal tissues (1). By killing cancer cells and damaging proteins and structures within cells (2), hyperthermia may shrink tumors.
Hyperthermia is under study in clinical trials (research studies with people) and is not widely available.
Hyperthermia usually is taken to mean a body temperature that is higher than normal. High body temperatures are often caused by illnesses, such as fever or heat stroke. But hyperthermia can also refer to heat treatment – the carefully controlled use of heat for medical purposes. Here, we will focus on how heat is used to treat cancer.
When cells in the body are exposed to higher than normal temperatures, changes take place inside the cells. These changes can make the cells more likely to be affected by other treatments such as radiation therapy or chemotherapy. Very high temperatures can kill cancer cells outright (thermal ablation), but they also can injure or kill normal cells and tissues. This is why hyperthermia must be carefully controlled and should be done by doctors who are experienced in using it.
Current instruments can deliver heat precisely, and hyperthermia is being used (or studied for use) against many types of cancer.
❯ Head and neck
❯ Sarcomas (soft tissues)
This type of hyperthermia delivers very high heat to a small area of cells or a tumor. Local hyperthermia can treat cancer without surgery.
Different forms of energy may be used, including:
✔ Radio waves
✔ Ultrasound waves
Heat may be delivered using:
✔ An external machine to deliver heat to tumors near the surface of the body.
✔ A probe to deliver heat to tumors within a body cavity, such as the throat or rectum.
✔ A needle-like probe to sends radio wave energy directly into the tumor to kill cancer cells. This is called radiofrequency ablation (RFA). It is the most common type of local hyperthermia. In most cases, RFA treats liver, kidney, and lung tumors that cannot be taken out with surgery.
This type of hyperthermia uses low heat on larger areas, such as an organ, limb, or a hollow space inside the body.
Heat may be delivered using these methods:
✔ Applicators on the surface of the body focus energy on a cancer inside the body, such as cervical or bladder cancer.
✔ Some of the person's blood is removed, heated, and then returned back to the limb or organ. This is often done with chemotherapy drugs. This method treats melanoma on the arms or legs, as well as lung or liver cancer.
✔ Doctors heat chemotherapy drugs and pump them into the area around the organs in a person's belly. This is used to treat cancers in this area.
This treatment raises a person's body temperature as though they have a fever. This helps chemotherapy work better to treat cancer that has spread (metastasized). Blankets, warm water, or a heated chamber are used to warm the person's body. During this therapy, people sometimes get medicines to make them calm and sleepy.
During hyperthermia treatments, some tissues may get very hot. This can cause:
✔ Discomfort or pain
Other possible side effects include:
✔ Blood clots
Whole-body hyperthermia can cause:
✔ Nausea and vomiting