Experimental cancer treatment
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Experimental cancer treatments are medical therapies intended or claimed to treat cancer (see also tumor) by improving on, supplementing or replacing conventional methods (surgery, chemotherapy, radiation, and immunotherapy).
The entries listed below vary between theoretical therapies and treatments that will most likely become standard procedures within the next few years. Many of these treatments will only help against specific forms of cancer. It is not a list of treatments widely available at hospitals!
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Angiostatic-based treatments
Every solid tumor (in contrast to liquid tumors like leukemia) needs to generate blood vessels to keep it alive once it reaches a certain size. Usually, blood vessels are not built elsewhere in an adult body unless tissue repair is actively in process. The anti-angiogenesis (angiostatic) agent endostatin and related chemicals can suppress the building of blood vessels, preventing the cancer from growing indefinitely. In tests with patients, the tumor became inactive and stayed that way even after the endostatin treatment was finished. The treatment has very few side effects but appears to have very limited selectivity. Other angiostatic agents like thalidomide and natural plant-based substances are being actively investigated.
Bacterial treatments
Chemotherapeutic drugs have a hard time penetrating tumors to kill them at their core because these cells may be dead or lack a good blood supply. Researchers have been using anaerobic bacteria, such as Clostridium novyi, to consume the interior of oxygen-poor tumours. These should then die when they come in contact with the tumour's oxygenated sides, meaning they would be harmless to the rest of the body. A major problem has been that bacteria don't consume all parts of the malignant tissue. However combining the therapy with chemotheraputic treatments has largely proven to solve this problem.
Gene therapy
Introduction of tumor suppressor genes into rapidly dividing cells has been thought to slow down or arrest tumor growth. Another use of gene therapy is the introduction of enzymes into these cells that make them susceptible to particular chemotherapy agents; studies with introducing thymidine kinase in gliomas, making them susceptible to aciclovir, are in their experimental stage.
Thermal therapy
Localized application of heat has been proprosed as a technique for the treatment of malignant tumours. Intense heating will cause denaturation and coagulation of cellular proteins, rapidly killing cells within a tumour.
More prolonged moderate heating to temperatures just a few degrees above normal can cause more subtle changes. A mild heat treatment combined with other stresses can cause cell death by apoptosis. There are many biochemical consequences to the heat shock response within in cell, including slowed cell division and increased sensitivity to ionizing radiation therapy.
There are many techniques by which heat may be delivered. Some of the most common involve the use of focused ultrasound (FUS), microwave heating, induction heating, or direct application of heat through the use of heated saline pumped through catheters.
One of the challenges in thermal therapy is delivering the appropriate amount of heat to the correct part of the patient's body. A great deal of current research focuses on precisely positioning heat delivery devices (catheters, microwave and ultrasound applicators, etc.) using ultrasound or magnetic resonance imaging. Clinicians also hope to use advanced imaging techniques to monitor heat treatments in real time—heat-induced changes in tissue are sometimes perceptible using these imaging instruments.
Complementary and alternative cancer treatment
See main article: Complementary and alternative medicine
In the year 2000, the American Cancer Society published American Cancer Society's Guide to Complementary and Alternative Cancer Methods. There are over 200 substances and therapies in this book, and while there is a varying degree of success with each of the methods, it appears that some of the techniques will work at times, however no technique will work in all situations, which, practitioners claim, is similar to the success rate of conventional techniques. Many of these treatements are similar to ancient ways of dealing with disease. According to practitioners of such techniques, various options are available to anyone who wants this information, however, they caution that discretion is advised no matter what methods a person chooses to pursue.
Dubious therapies
Diet therapy
In late 1940-s Max Gerson proposed a therapy that is claimed to be successful in the treatment of advanced cancer, normalizing metabolism and helping the body's immune system act on cancer cells. It is a high potassium, low sodium (saltless) diet, with no fats or oils, and high in fresh raw fruits and vegetables and their juices. (See for instance the lecture [1] (http://gerson-research.org/docs/GersonM-1978-1/), and the book A Cancer Therapy: Results of Fifty Cases, by Max Gerson, M.D.). Other scientists doubt the ability of these treatments to cure cancer, and point to the lack of detailed publication of their results ([2] (http://www.amazon.com/exec/obidos/tg/detail/-/0961152621/)).
The quackwatch.com site (http://www.quackwatch.com) writes about Gerson method[3] (http://www.quackwatch.org/01QuackeryRelatedTopics/cancer.html)
"In 1947, the NCI reviewed ten cases selected by Dr. Gerson and found his report unconvincing. That same year, a committee appointed by the New York County Medical Society reviewed records of 86 patients, examined ten patients, and found no evidence that the Gerson method had value in treating cancer."
"A recent review of the Gerson treatment rationale concluded: (a) the "poisons" Gerson claimed to be present in processed foods have never been identified, (b) frequent coffee enemas have never been shown to mobilize and remove poisons from the liver and intestines of cancer patients, (c) there is no evidence that any such poisons are related to the onset of cancer, (d) there is no evidence that a "healing" inflammatory reaction exists that can seek out and kill cancer cells (Green S. A critique of the rationale for cancer treatment with coffee enemas and diet. JAMA 268:3224-3227, 1992)."
"Between 1980 and 1986 at least 13 patients treated with Gerson therapy were admitted to San Diego area hospitals with Campylobacter fetus sepsis attributable to the liver injections. None of the patients was cancer-free, and one died of his malignancy within a week. Five were comatose due to low serum sodium levels, presumably as a result of the "no sodium" Gerson dietary regimen. (Ginsberg MM and others. Campylobacter sepsis associated with "nutritional therapy" -- California. MMWR 30:294-295, 1981)"
"Charlotte Gerson claims that treatment at the clinic has produced high cure rates for many cancers. In 1986, however, investigators learned that patients were not monitored after they left the facility [19]. Although clinic personnel later said they would follow their patients systematically, there is no published evidence that they have done so. A naturopath who visited the Gerson Clinic in 1983 was able to track 21 patients over a 5-year period (or until death) through annual letters or phone calls. At the 5-year mark, only one was still alive (but not cancer-free); the rest had succumbed to their cancer (Austin S, Dale EB, DeKadt S. Long-term follow-up of cancer patients using Contreras, Hoxsey and Gerson therapies. Journal of Naturopathic Medicine 5(1):74-76, 1994)."
Johanna Budwig proposed another diet therapy he claims can treat cancer. As with Max Gerson, most oncologists do not believe that a diet can treat cancer. Reports of dramatic remissions as a result of the Budwig diet are anecdotal, and not supported by peer-reviewed research. (On the other hand, his diet is good from a nutritional point of view and probably cannot do harm.)
Insulin Potentiation Therapy
In insulin potentiation therapy, low-dose insulin is given in conjunction with low-dose chemotherapy. Its proponents claim to be effective while dramatically reducing side effects. However, there is no evidence that it works other than anecdotal [4] (http://www.quackwatch.org/01QuackeryRelatedTopics/Cancer/ipt.html).
Fasting Therapy
Long-term fasting has been reported to work against malignant tumours. A specific mechanism for this effect has not been identified, and studies to date are merely anecdotal.
External links
- American Cancer Society (http://www.cancer.org)
- National Cancer Institute (http://www.nci.nih.gov)
- Nature Reviews Cancer website (http://www.nature.com/nrc/index.html)
- "Questionable Cancer Therapies" (http://www.quackwatch.org/01QuackeryRelatedTopics/cancer.html)
- Criticism of dubious therapies (http://www.quackwatch.org/00AboutQuackwatch/altseek.html)