What is Hyperthermia?
Hyperthermia is a type of cancer treatment in which tumors are exposed to elevated body temperatures, between 104˚ and 113°F. Research has shown that high temperatures can damage and kill cancer cells, usually with minimal injury to normal tissues. Higher temperatures selectively damage cells that are hypoxic and have low pH, a condition of tumor cells and not a condition of normal cells. Hyperthermia has been shown to inhibit cellular repair mechanisms, induce heat-shock proteins, denature proteins, induce apoptosis, and inhibit angiogenesis.
- Tumour hypoxia
- is the situation where tumor cells have been deprived of oxygen. As a tumor grows, it rapidly outgrows its blood supply, leaving portions of the tumor with regions where the oxygen concentration is significantly lower than in healthy tissues.
- Heat shock proteins
- are a family of proteins that are produced by cells in response to exposure to stressful conditions.
- is the process of programmed cell death (PCD)
- is the physiological process through which new blood vessels form from pre-existing vessels.
What is Superficial Hyperthermia?
Superficial hyperthermia approaches are used to treat tumors that are in or just below the skin. External applicators are positioned around or near the appropriate region, and energy is focused on the tumor to raise its temperature. The BSD-500 is used shown excellent results in clinical studies on recurrent and progressive Melanoma, Squamous or basal-cell carcinoma, Sarcoma and Adenocarcinoma.
What is Interstitial Hyperthermia?
The BSD-500 can bring therapeutic hyperthermia to solid tumors via catheters placed into the body, usually done during the bracytherapy process. The BSD-500 delivers energy to a patient using a power source and an array of multiple antennas inserted into the catheters. RF energy is applied at 915 MHz to provide an optimized heating zone targeted to the tumor region by utilizing the adjustment of, phase, and amplitude from multiple power sources.
What is Deep Regional Hyperthermia?
The BSD-2000 provides deep regional therapeutic hyperthermia to solid tumors by applying radiofrequency (RF) energy at the frequency range of 75 to 120 MHz. The BSD-2000 delivers energy to a patient using a power source and an array of multiple antennae that surround the patient’s body. The system provides an optimized heating zone targeted to the tumor region by utilizing the adjustment of frequency, phase, and amplitude from multiple power sources. The energy can be focused electronically to the tumor region, thus providing dynamic control of the heating delivered to the tumor region.
How does Hyperthermia work with Radiation Therapy?
Hyperthermia increases the effectiveness of radiation therapy due to the independent cytotoxic effects of hyperthermia combined with its radiosensitizing effects. Hyperthermia increases blood flow, resulting in improved tissue oxygenation and thus increased radiosensitivity. Hyperthermia also interferes with cellular repair of the DNA damage caused by radiation. Hyperthermia damages cells that are hypoxic, have a low pH, and are in the S-phase of division, which are all conditions that make cells resistant to radiation therapy. The addition of hyperthermia does not usually increase toxicity of radiation therapy.
How does Hyperthermia work with Chemotherapy?
Hyperthermia used in combination with chemotherapy increases the drug concentration in the tumor region duet to increased blood flow, thus raising the effectiveness of cytostatic drugs. In addition hyperthermia has been proven to enhance drug toxicity in cells resistant to many drugs.
Why is it more commonly used in Recurrent Cancer Treatment?
There is a lifetime limit to the amount of radiation a patient can be exposed to. So doctors must look for alternative therapies when treating cancer that has returned. This is where clinical trials flourish. It was found that hyperthermia sensitized tumors to radiation treatment allowing Radiation Oncologist to treat recurrent cancer with less toxicity.
Is there Clinical Evidence?
Numerous clinical trials have studied hyperthermia in combination with radiation therapy and/or chemotherapy. These studies have focused on the treatment of many types of cancer, including sarcoma, melanoma, and cancers of the head and neck, brain, lung, esophagus, breast, bladder, rectum, liver, appendix, cervix, and peritoneal lining (mesothelioma). Many of these studies have shown a significant reduction in tumor size when hyperthermia is combined with other treatments.
Is it Safe?
The Hyperthermia process does not harm, is non-toxic and is non-invasive. Most normal tissues are not damaged during hyperthermia if the temperature remains under 111°F. However, due to regional differences in tissue characteristics, higher temperatures may occur in various spots. This can result in burns (9.9%), pain (8.4%), ulceration (3.6%) and infection (1.8%). Perfusion techniques can cause tissue swelling, blood clots, bleeding, and other damage to the normal tissues in the perfused area; however, most of these side effects are temporary. (National Institute of Health)
It may be defined as minimally invasive when used with radiotherapy. In this case, hyperthermia RF antennas are placed in existing catheters that were placed in the body by the Radiation therapy process.
Hyperthermia is almost always used with other forms of cancer therapy, such as radiation therapy and chemotherapy (1, 3). Hyperthermia may make some cancer cells more sensitive to radiation or harm other cancer cells that radiation cannot damage. When hyperthermia and radiation therapy are combined, they are often given within an hour of each other. Hyperthermia can also enhance the effects of certain anticancer drugs.