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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).

Cancer /ˈkænsə(r)/ ( listen) (medical term: malignant neoplasm) is a class of diseases in which a group of cells display uncontrolled growth (division beyond the normal limits), invasion (intrusion on and destruction of adjacent tissues), and sometimes metastasis (spread to other locations in the body via lymph or blood). These three malignant properties of cancers differentiate them from benign tumors, which are self-limited, and do not invade or metastasize. Most cancers form a tumor but some, like leukemia, do not. The branch of medicine concerned with the study, diagnosis, treatment, and prevention of cancer is oncology.

Cancer affects people at all ages with the risk for most types increasing with age.[1] Cancer caused about 13% of all human deaths in 2007[2] (7.6 million).[3]

Cancers are caused by abnormalities in the genetic material of the transformed cells.[4] These abnormalities may be due to the effects of carcinogens, such as tobacco smoke, radiation, chemicals, or infectious agents. Other cancer-promoting genetic abnormalities may randomly occur through errors in DNA replication, or are inherited, and thus present in all cells from birth. The heritability of cancers is usually affected by complex interactions between carcinogens and the host's genome.

Genetic abnormalities found in cancer typically affect two general classes of genes. Cancer-promoting oncogenes are typically activated in cancer cells, giving those cells new properties, such as hyperactive growth and division, protection against programmed cell death, loss of respect for normal tissue boundaries, and the ability to become established in diverse tissue environments. Tumor suppressor genes are then inactivated in cancer cells, resulting in the loss of normal functions in those cells, such as accurate DNA replication, control over the cell cycle, orientation and adhesion within tissues, and interaction with protective cells of the immune system.

Definitive diagnosis requires the histologic examination of a biopsy specimen, although the initial indication of malignancy can be symptomatic or radiographic imaging abnormalities. Most cancers can be treated and some cured, depending on the specific type, location, and stage. Once diagnosed, cancer is usually treated with a combination of surgery, chemotherapy and radiotherapy. As research develops, treatments are becoming more specific for different varieties of cancer. There has been significant progress in the development of targeted therapy drugs that act specifically on detectable molecular abnormalities in certain tumors, and which minimize damage to normal cells. The prognosis of cancer patients is most influenced by the type of cancer, as well as the stage, or extent of the disease. In addition, histologic grading and the presence of specific molecular markers can also be useful in establishing prognosis, as well as in determining individual treatments.To understand treatment of cancer you need to know what cancer is. The top cancers in america: 1.Lung cancer Lung cancer kills more American than any other cancer. The average annual death toll fro recent years is more than 90,000 men and 45,000 women. 2.Colon-rectum cancer It is the second leading cause of cancer death in the US. Each year it claims an estimated 55,000 lives, and produces about 150,000 new cases- more than any other kind of cancer except skin cancer. It afflicts men and women about equally. 3.Breast cancer Breast cancer is the most common of cancers affecting woman. It kills more women than any other kind of cancer. About 150,000 women in the US develop breast cancer each year, and 35% die of the disease. 4.Stomach Cancer Stomach cancer is still one of the more frequently diagnosed types of cancer and the death rate is relatively high, at nearly 10 per 100,000population. Men are twice as likely to be victims of stomach cancer as women. 5.Prostate Cancer Cancer of the prostate is the most common cancers among men and is second only to lung cancer as a lethal type of tumor for men. About 30,000 people die of prostate cancer each year.

The entries listed below vary between theoretical therapies to unproven controversial therapies. Many of these treatments are alleged to only help against specific forms of cancer. It is not a list of treatments widely available at hospitals.

Bacterial treatments

Chemotherapeutic drugs have a hard time penetrating tumors to kill them at their core because these cells may 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 can help to solve this problem.

Another strategy is to use anaerobic bacteria that have been transformed with an enzyme that can convert a non-toxic prodrug into a toxic drug. With the proliferation of the bacteria in the necrotic and hypoxic areas of the tumour the enzyme is expressed solely in the tumour. Thus a systemically applied prodrug is metabolised to the toxic drug only in the tumour. This has been demonstrated to be effective with the non pathogenic anaerobe Clostridium sporogenes.^[1]

Photodynamic Therapy

Photodynamic Therapy is generally a non-invasive treatment using a combination of light and a photosensitive drug. Photodynamic Therapy, also known as PDT, uses photosensitive drugs (such as 5-ALA, Foscan, Metvix, Tookad, WST09, WST11, Photofrin and Visudyne) which are triggered by light of a specific wavelength.

HAMLET (human alpha-lactalbumin made lethal to tumor cells)

HAMLET (human alpha-lactalbumin made lethal to tumor cells) is a molecular complex derived from human milk that kills tumor cells by a process resembling programmed cell death. HAMLET causes apoptosis and tumor cell death in tumor cells. HAMLET has broad antitumor activity in vitro, and its therapeutic effect has been confirmed in vivo in a human glioblastoma rat xenograft model, in patients with skin papillomas and in patients with bladder cancer.^[2]

Gene therapy

Introduction of tumor suppressor genes into rapidly dividing cells has been thought to slow down or arrest tumor growth. Adenoviruses are a commonly utilized vector for this purpose. Much research has focused on the use of adenoviruses which cannot reproduce, or reproduce only to a limited extent, within the patient to ensure safety via the avoidance of cytolytic destruction of noncancerous cells infected with the vector. However, new studies focus on adenoviruses which can be permitted to reproduce, and destroy cancerous cells in the process, since the adenoviruses' ability to infect normal cells is substantially impaired, potentially resulting in a far more effective treatment.^[3][4] 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.

Telomerase therapy

Because most malignant cells rely on the activity of the protein telomerase for their immortality, it has been proposed that a drug which inactivates telomerase might be effective against a broad spectrum of malignancies. At the same time, most healthy tissues in the body express little if any telomerase, and would function normally in its absence. Currently, Inositol hexaphosphate, which is available over-the-counter, is undergoing testing in cancer research due to its telomerase-inhibiting abilities.^[5]

A number of research groups have experimented with the use of telomerase inhibitors in animal models, and as of 2005 and 2006 phase I and II human clinical trials are underway. Geron Corporation, is currently conducting two clinical trials involving telomerase inhibitors. One uses a vaccine (GRNVAC1) and the other uses a lipidated drug (GRN163L).

Hyperthermia therapy

Localized and whole-body application of heat has been proposed 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 or HIFU), microwave heating, induction heating, magnetic hyperthermia or direct application of heat through the use of heated saline pumped through catheters. Experiments have been done with carbon nanotubes that selectively bind to cancer cells. Lasers are then used that pass harmlessly through the body, but heat the nanotubes, causing the death of the cancer cells. Similar results have also been achieved with other types of nanoparticles including gold-coated nanoshells and nanorods which exhibit certain degrees of 'tunability' of the absorption properties of the nanoparticles to the wavelength of light for irradiation. The success of this approach to cancer treatment rests on the existence of an 'optical window' in which biological tissue (i.e,. healthy cells) are completely transparent at the wavelength of the laser light while nanoparticles are highly absorbing at the same wavelength. Such a 'window' exists in the so-called near infrared region of the electromagnetic spectrum. In this way, the laser light can pass through the system without harming healthy tissue and only diseased cells, where the nanoparticles reside, get hot and are killed.

Magnetic hyperthermia makes use of magnetic nanoparticles, which can be injected into tumours and then generate heat when subjected to an alternating magnetic field.^[6]

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, as well as of developing new types of nanoparticles that make them particularly efficient absorbers while offering little or no concerns about toxicity to the circulation system. 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.

Dichloroacetate (DCA)

Dichloroacetate has been found to shrink tumors in vitro in rats.^[7] These studies received attention in the media,^[8] and some doctors began controversially using the chemical off-label.^[9] A small clinical trial (enrollment- up to 50 patients) has been planned with patients originating from the Edmonton area.^[10][11]

Quercetin

In vitro, quercetin shows some antitumor activity. Cultured skin and prostate cancer cells showed significant mortality (compared to nonmalignant cells) when treated with a combination of quercetin and ultrasound^[12] Note that ultrasound also promotes topical absorption by up to 1,000 times, making the use of topical quercetin and ultrasound wands an interesting proposition.^{[citation needed]}

High dietary intake of fruits and vegetables is associated with reduction in cancer, and some scientists suspect quercetin may be partly responsible. Research shows that quercetin influences cellular mechanisms in vitro and in animal studies, and there is limited evidence from human population studies that quercetin may reduce the risk of lung cancer.^[13][14]

Non-invasive RF cancer treatment

This preclinical treatment involves using radio waves to heat up tiny metals which are implanted in cancerous tissue. Gold nanoparticles or carbon nanotubes are the most likely candidate. Promising preclinical trials have been conducted,^[15][16] although clinical trials may not be held for another few years.^[17]

Complementary and alternative

Complementary and alternative medicine (CAM) treatments are the diverse group of medical and health care systems, practices, and products that are not part of conventional medicine.^[18] "Complementary medicine" refers to methods and substances used along with conventional medicine, while "alternative medicine" refers to compounds used instead of conventional medicine.^[19] CAM use is common among people with cancer; a 2000 study found that 69% of cancer patients had used at least one CAM therapy as part of their cancer treatment.^[20] Most complementary and alternative medicines for cancer have not been rigorously studied or tested. Some alternative treatments which have been investigated and shown to be ineffective continue to be marketed and promoted.^[21]

Yagya Therapy : The Indian Ayurvedic Method

According to the scholars of ancient Ayurveda texts, there are hundred and eight prominent nuclei that are richest sources and repositories of prana (vital spiritual energy) inside the human body. Dysfunctioning of any of these may lead to immediate death. Blockage or disturbance in the flow of prana in any of these deep "marma sthanas" is said to be the cause of cancer.

According to the scholars of ancient Ayurveda texts, there are hundred and eight prominent nuclei that are richest sources and repositories of prana (vital spiritual energy) inside the human body. Dysfunctioning of any of these may lead to immediate death. Blockage or disturbance in the flow of prana in any of these deep "marma sthanas" is said to be the cause of cancer. Abnormal levels of tridoshas is also described as a cause of cancerous transformation of blood and other body functions. The scriptures give details of different manifestations of prana in biochemical and physiological functions.

The Indian (Ayurvedic) prescription of fresh wheat grass juice has been recognized by many modern doctors, as it helps increasing the vitality and resistance of patients. Patients who drink a glass of this every day are found to bear the side effects of chemotherapy much easily than other patients in similar state of disease and treatment. Moreover, the rate and frequency of cure is also found to be higher in such patients. The Brahmvarchas Research Center of Shantikunj Hardwar has contributed significantly by publishing the information on this easy remedy in the Hindi magazine "Akhand Jyoti" more than a decade ago.

For the details of the relatively simple curative procedure, one may follow the link given in the reference.^[22]

Controversial therapies

Diet therapy

Johanna Budwig proposed a diet therapy claimed to treat cancer. Most oncologists have a belief that a diet alone cannot 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, her diet is good from a nutritional point of view to counteract some side-effects of other treatments.) Some basic research on flax oil (preferred by Budwig) is available.^{[23][24][25][26][27]}

Unfortunately, the proponents of this approach have been consistently unable to produce a single surviving patient who meets all of these criteria:

1. was diagnosed by an independent oncologist instead of by a proponent,
2. actually appears to have been cured, and
3. did not undergo conventional cancer therapies which could reasonably explain the successful treatment.

Insulin potentiation therapy

In insulin potentiation therapy (IPT), insulin is given in conjunction with low-dose chemotherapy. Its proponents claim insulin therapy increases the uptake of chemotherapeutic drugs by malignant cells, permitting the use of lower total drug doses and reducing side effects.

Some In vitro studies have demonstrated the principle of IPT.^[28][29]

The first clinical trial of IPT for treating breast cancer was done in Uruguay and published in 2003/2004. Insulin combined with low-dose methotrexate (a chemotherapy drug) resulted in greatly increased stable disease, and much reduced progressive disease, compared with insulin or low-dose methotrexate alone. Although the study was very small (30 women, 10 per group), the results appear to be very promising.^[30]

References

External links

• American Cancer Society
• National Cancer Institute
• Dichloroacetate (DCA) Research
• Nature Reviews Cancer website
• Audio-video Physician Interviews on Cancer Treatment Breakthroughs
• "Questionable Cancer Therapies"