Hyperthermia

Hyperthermia
Hyperthermia

Hyperthermia involves raising the body’s core temperature as a means of eradicating tumors. The treatment simulates fever. Some therapies actually bring on fever through the introduction of fever-causing organisms, while others raise body temperature by directly heating the blood.

Hyperthermia dates back to investigations begun in 1883 by William B. Coley, M.D., a general surgeon at New York City’s Memorial Hospital. Coley was intrigued by a paper published in 1868 by an American family physician named Busch. Busch’s paper described a patient with an untreatable sarcoma of the face.

Though Busch had been unable to help the patient overcome her cancer, the patient went into remission spontaneously after suffering a bout of the skin infection known as erysipelas. The erysipelas resulted in a high fever ranging from 104°F to 105.8°F (40°C to 41°C).

Over the next 20 years, Coley performed a series of experiments to study the effects of elevated temperature on various forms of cancer. After experimenting on animals, Coley moved to treating human cancer patients, injecting them with bacteria to induce high fevers.

The bacteria he used are known as Coley’s toxins. He reported much success with his method, especially against soft-tissue sarcomas and sarcomas of the bone. Yet his treatment also had serious side effects due to the infections he was introducing.

In spite of its drawbacks, Coley’s work intrigued a few other researchers. A study published in Cancer Research in 1957 showed that in a review of 450 cases of supposed spontaneous remissions of cancer, 150 of the patients had suffered acute infections that raised their body temperatures.

In the 1960s, a Cleveland surgeon and breast cancer specialist, George Crile Jr., published several studies of his experiments in eliminating tumors in mice using heat.

Another doctor, Harry Leveen of South Carolina, began building machines that used radio frequencies to heat either the whole body or affected parts. But Leveen’s machines were not approved by the Food and Drug Administration (FDA) and Leveen took his inventory to the University of Bangor in Wales.

Hyperthermia did not receive much attention in the United States after this point, but practitioners in other countries, particularly Germany, Italy, and Mexico, have reported good results with it. An international congress on hyperthermia has been held each year since 1977.

Benefits

Hyperthermia has been shown in several studies to reduce malignant tumors either alone or in combination with chemotherapy. A 1998 study of patients with breast and ovarian cancer found that hyperthermia therapy increased the effectiveness of chemotherapy.

This study suggested that patients undergoing hyperthermia might be successfully treated with lower doses of chemotherapy. A 2003 study demonstrated that women with breast cancer were less likely to experience spread of the cancer to distant lymph nodes or the lungs if they received a combination of whole-body hyperthermia and chemotherapy.

A form of localized hyperthermia used to treat benign enlarged prostate glands can be performed in a doctor’s office in as little as an hour, and this method does not have the side effects, such as impotence and incontinence, that often accompany traditional prostate surgery.

Newer methods of hyperthermia involving noninvasive (no penetration of skin) microwave technology have been introduced in other countries and were making their way to the United States in early 2002.

This technology offered excellent results for some cancer patients in improving five-year survival rates for some aggressive forms of cancer when combined with other cancer therapy procedures.

Description

Hyperthermia therapy involves raising the body’s internal temperature, and this can be brought about by several methods. Hyperthermia can involve the whole body, or just an affected local region.

For reducing an enlarged prostate, doctors use a device approved by the FDA in 1996 that delivers microwaves to the prostate, while water cools the surrounding tissue to prevent burns.

For whole-body hyperthermia, a method used in Europe employs a tent-like device that delivers infrared light to the body. The patient is injected with toxins to provoke a mild fever and then monitored under lights.

The lights produce a slow rise in temperature, optimally to 107.6°F (42°C). A prominent practitioner of hyperthermia in Mexico directly heats the patient’s blood. Under sedation, the doctor inserts a catheter into each leg near the groin. The two catheter tubes are connected to a heat exchanger.

The heat exchanger heats the patient’s blood, bringing up the entire body temperature. The patient is monitored by thermometers in the esophagus and rectum. Body temperature is raised to 107.6°F (42°C) for about one hour.

Side effects

The side effects of hyperthermia depend on how it is delivered. Cardiac problems are possible. The patient should be closely monitored during the procedure and after. For treatment of the prostate, localized hyperthermia seems to be without the side effects of traditional prostate surgery.

Research and general acceptance

Though research into hyperthermia as a cancer treatment began in the United States, most active practitioners are in Europe or Mexico as of 2004. However, the heat therapy for prostate enlargement was approved in the United States in 1996.

Localized hyperthermia was being studied in the late 1990s for treatment of other conditions, including menorrhagia (heavy menstrual periods) and malignant tumors of the liver and rectum. Whole body hyperthermia continues to be studied and tested for its impact on cancers, and a test underway in 1999 in Texas examined this therapy for patients with AIDS.

Several studies in 2003 showed hyperthermia’s positive effects on cellular immune response in cancer patients, especially when used along with chemotherapy. One study suggested that the effectiveness of certain chemotherapy drugs used for leukemia patients could be enhanced by adding hyperthermia to the treatment.

Training and certification

Practitioners performing hyperthermia are certified medical doctors and such trained assistants as nurses and anesthesiologists.

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