Hyperthermia
Hyperthermia
Definition
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.
Origins
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 Re-search 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 & 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 & certification
Practitioners performing hyperthermia are certified medical doctors and such trained assistants as nurses and anesthesiologists.
Resources
PERIODICALS
"BSD Medical Licenses Right to NIH Non-invasive Deep Hyperthermia Cancer Therapy." BIOTECH Patent News (February 2002).
"Cancer (therapy)." Women's Health Weekly (August 10, 1998): 17.
"Hyperthermia and Ifosfamide Induced Cytotoxicity is Subadditive." Proteomics Weekly (March 24, 2003):10.
"Hyperthermia Improves Immune Response to Human Hepato-cellular Carcinoma." Vaccine Weekly (July 30, 2003):10.
Jack, David. "Waxing Hot and Cold in the Surgical Arena." The Lancet (April 11, 1998): 1110.
Key, Sandra, and Michelle Marble. "Hyperthermia Treatment Evaluated" Cancer Weekly Plus (February 8, 1999): 14.
Walker, Morton. "Medical Journalist Report of Innovative Biologics: Whole Body Hyperthermia Effect on Cancer." Townsend Letter for Doctors & Patients (June 30, 1998): 60–66.
"Whole-body Hyperthermia and Metronomic Chemotherapy Prevent Cancer Metastasis." Angiogenesis Weekly (April 11, 2003):4.
Wu, Corrina, Shannon Brownlee, and Anna Mulrine. "Zapping a Problem Prostate." U.S. News & World Report (May 20, 1996): 71.
Angela Woodward
Teresa G. Odle
Hyperthermia
Hyperthermia
Definition
Hyperthermia is the use of therapeutic heat to treat various cancers on and inside the body.
Purpose
The purpose of hyperthermia is to shrink and hopefully destroy cancer without harming noncancerous cells. It can be used to treat cancer in many areas of the body, including the brain, thyroid, lung, breast, and prostate. It is thought that high temperatures, up to 106 degrees Fahrenheit, can help shrink cancerous tumors. Hyperthermia is starting to be more widely used because it does not have side effects like other forms of cancer treatment such as radiation or chemotherapy . In some instances, hyperthermia is used at the same time with other forms of cancer therapy.
Through years of research, it has been found that the effectiveness of some forms of radiation therapy and chemotherapy are enhanced when combined with hyperthermia.
Although the treatment was considered experimental 15-20 years ago, its proponents believe that the treatment has been accepted by many physicians, and that use of hyperthermia will increase as more cancer centers install the high-tech equipment necessary for regional and whole body hyperthermia. (Currently, cancer care centers offering this treatment are limited.) In 2001, the American Cancer Society acknowledges that hyperthermia can make the cancer cells of some cancers more responsive to treatment, but still considers the treatment experimental, especially in whole-body form. The National Institutes of Health are sponsoring ongoing clinical trials studying hyperthermia.
Precautions
Patients who have extensive metastasis (spreading of the cancer throughout their body) may not be good candidates for hyperthermia. Patients need to be free of major infections and able to tolerate the high temperatures of the treatment. Caution must be used when areas of the body are heated with external heat sources such as heating pads to avoid potentially dangerous burns.
Description
Hyperthermia can be used on the body from very small areas of the body to the entire body itself. Local hyperthermia refers to heating just one area of body, usually where the tumor is located. Heat can be applied from outside the body using microwaves or high-frequency radio waves. Heat can be applied from inside the body or even inside the tumor itself by the use of thin, heated wires, small tubes filled with hot water, or implanted microwave antennae.
If heat is used to treat an entire organ or limb, it is referred to as regional hyperthermia. High-energy magnets or other devices that produce high energy, and thus heat, are placed over the larger areas to be heated. Another method of regional hyperthermia is the use of perfusion. Hyperthermia perfusion uses the patient's own blood; the blood is removed, heated outside the body, then pumped back into the area that contains the cancer.
For treatment of cancers that have spread throughout the body, whole-body hyperthermia can be considered. Various methods are used to heat up a patient's entire body, including warm-water or electric blankets, hot wax, or thermal chambers which are very much like incubators used to warm newborn babies, except much larger.
Preparation
There are generally no advance preparations needed for a patient considering the use of hyperthermia.
Risks
The major risks of hyperthermia use are pain and external burns. Heat applied directly to the skin can cause minor discomfort to significant pain, especially when high temperatures are used. Blistering and actual burning of the skin can also occur at higher temperatures, although with careful application of the hyperthermia, these side effects are very rare.
Normal Results
The goal of hyperthermia is to control the growth and shrink hyperthermia-sensitive tumors. As stated earlier, hyperthermia can also be used to help sensitize tumors to other cancer treatment modalities such as radiation and chemotherapy.
Abnormal Results
There are generally no abnormal results seen with the use of hyperthermia. Side effects, such as pain and burning from external heat sources, can be minimized with careful application of the heat.
Resources
BOOKS
Abeloff, D. Martin, James O. Armitage, Allen S. Lichter, and John E. Niederhuber. Clinical Oncology. New York: Churchill Livingstone, 2000.
Bicher, I. Haim, John R. McLaren, and Giuseppe M. Pigliucci, ed. Consensus on Hyperthermia for the 1990s. New York: Plenum Press, 1990.
Freeman, L. Michael and Kurt J. Henle. "Hyperthermia." InEncyclopedia of Cancer, Volume II. Academic Press, 1997: 888-900.
Edward R. Rosick, D.O., M.P.H.
hyperthermia
hy·per·ther·mi·a / ˌhīpərˈ[unvoicedth]ərmēə/ • n. Med. the condition of having a body temperature greatly above normal.DERIVATIVES: hy·per·ther·mic / -ˈ[unvoicedth]ərmik/ adj.
hyperthermia
1. exceptionally high body temperature (about 41°C or above). See fever.
2. treatment of disease by inducing fever. Compare hypothermia.