Herbal Medicine in the Treatment of Cancer

By: Chris Aoki - 1998
University of Hawaii at Manoa John A. Burns School of Medicine


The war on cancer that began in 1970 is still far from over. Despite 30 billion dollars spent on research and treatment, the mortality rate for cancer is 6% higher in 1997 than it was in 1970 (Bailar III and Gornik, 1997). This has frustrated both patients and physicians, and has led some patients to actively seek out non-Western healing practices. One of the most popular is herbal medicine. In 1996 US herbs sales were 12 billion dollars with 63% of the population expecting to make herbs a part of their daily regimen within 5 years (Landers, 1996). The popularity of the use of herbs to treat cancer poses a unique difficulty to health care professionals. Terminal cancer patients who have lost all hope with modern medicine are easy prey to scam artists who will offer dangerous products at high prices with promises of a cure. At the same time there may also be legitimate herbalist who offer products with great benefit to the cancer patient. Physician must be vigilant to those who seek to harm or take advantage of the patient. However they must also remain open minded to non-Western healing practices that have worked in some people for thousands of years. Many times this type of healing cannot be tested within the boundaries of Western science. In addition many people are rebelling against a scientific way of thinking, and instead, are going to their cultural and spiritual belief system. This is especially true of native Hawaiians, whose belief system had been largely oppressed and now are increasingly returning to the health practices that served them for thousands of years. Physicians in Hawaii need to be knowledgeable about the different treatments native Hawaiian medicine offers, in addition to the popular herbs used in the market. The purpose of this paper is to educate physicians about Hawaiian and non-Hawaiian herbs used to treat cancer and how to help patients make informed decisions about the use of herbal medicine to treat cancer. Herbs in Hawaiian medicine are but one facet of the intricate healing process involved in native Hawaiian healing. In general, disease processes in Hawaiian medicine stem from either problems within the person, inside a person's family or from outside influences. Before any diagnosis is made, things must be put right (ho'oponopono) with all the family members. If the disease process continued after ho'oponopono the kahuna determines the outside influence causing the disease. Some of these outside influences come in the form of cursing from an enemy. If the signs indicated that the illness was not from outside forces then it had to come from within the patient. In this case the disease was the result of an offense against either an akua 'aumakua (one of the great gods Ku, Kane, Kanaloa or Lono), an 'ohana 'aumakua (an ancestral family god) or one the kini akua (multitude of gods, many of them lesser spirits). Once a diagnosis is made a kahuna then performs many rituals and prayers until a correct form of treatment is decided. Treatments in Hawaiian medicine can be variable and consists of herbs, prayers and rituals depending on the kahuna (Gutmanis, 1987). While this form of medicine served Hawaiians well before the coming of Captain Cook, it was no longer effective in treating the diseases brought by the influx of immigrants to Hawaii. Native Hawaiian medicine needed to evolve to treat these new diseases that were decimating the population. One thing that was noticed was that as the diet of Hawaiians changed there was an increase in the amount of cancer and other diseases. Practitioners of la'au lapa'au decided that cancer and many other diseases could be prevented if Hawaiians stayed away from the foods with high cholesterol and fat that were introduced to these islands. But once cancer has started most practitioners' believe that treatment is mostly in conjunction with Western chemotherapy and radiation (Papa Kalua). Others believe that the use of popolo, ihi, alae, noni, and aloe can stop the growth of cancer (Henry Rapoza). While no formal scientific studies have been done on these herbs, physicians should take the time to talk to the practitioners who administer them. Much like Western medicine, Hawaiian medicine is an art with each practitioner having their own belief system about the efficacy of different treatments. In addition to Hawaiian herbs, many of the herbs popular on the market are beginning to show promising effects. This is a short summary of preliminary research that has shown benefits to taking these herbs. Astragalus membranaceus (Huang chi) has been used for thousands of years in Asia to stimulate the immune system. It has recently been shown in vitro to increase function of T lymphocytes in 13 cancer patients by 260% compared with untreated cells and by 160% compared with cells from healthy donors (Chu et al., 1988). In patients receiving chemotherapy it appears to help reduce the side effects, promote immune function and increase survival time (Boik, 1996). Some side effects that have been reported include low blood pressure, diuresis, dizziness, and fatigue (Hartland, 1996). Iscador is the trade name for extract of European mistletoe (Viscum album), has been used since the 1960's in Europe as an anticancer agent. A study investigating alterations in DNA repair in 14 breast cancer patients showed repairs averaging 2.7 times higher in 12 of the 14 who were treated parenterally with Iscador (Kovacs, et al., 1991). Side effects can stem from mistletoe being able to grow as a parasite of toxic host plants and absorb harmful alkaloids and glycosides. This has led to numerous poisoning and deaths (Spaulding, 1997). Studies are underway in the United States at the University of Texas Center for Alternative Medicine. Milk thistle (Silybum marianum gaietro) contains a wide variety of flavolignans (silymarin) that act as liver protection agents. Studies in mice have shown silymarin does exert a protective effect against a variety of toxins. Human trials have shown some effects in hepatitis and cirrhosis of various origins. Silymarin appears to effect undamaged liver cell plasma membrane, inhibiting the uptake of the toxins. It also appears to increase protein synthesis and have antioxidant properties (Tyler, 1993). Studies from Case Western Reserve University have shown that topical application of silymarin on mice resulted in almost complete inhibition of an epidermal carcinogen and prevented formation of pyrimidine dimers (potential cancer agents) in the skin after exposure to ultraviolet B sun rays. The data suggests that the compound could be a useful to decreasing tumor promoters (Agarwal et al, 1994). Bokemeyer et al. found that infusion of the flavonoid silibinin before cisplatin treatment significantly reduced glomerular and tubular kidney toxicity in a rat model without inhibiting the antitumor activity of the drug (1996). Thus it may serve as a useful adjunct for patients receiving chemotherapy that are especially nephrotoxic and hepatotoxic. Well-controlled studies on humans are still needed to ensure that no negative effects would occur with long time usage. To this date there have been no reports of adverse side effects. Pycnogenol is the trade name for a substance extracted from the French maritime pine tree. It contains oligomericproanthocyanide (a type of bioflavinoid) which are active free radical scavengers. Most of the studies have been done in France and study controls are unknown. In vitro studies in mice from a US study suggest that pycnogenol may be useful for preventing disorders associated with oxidative damage and can increase natural killer cell cytotoxicity (Rong et al., 1994). No side effects are found except for an occasional allergic reaction or diarrhea. Shiitake mushroom is an important herbal remedy in Asian medicine. Preliminary research has shown they contain an antitumor polysaccharide called lentinan. The sugar extract appears to stimulate production of T lymphocytes, macrophages, and natural killer cells (Chiara, 1987). Lentinan has been shown to have antitumor effects in humans and animals when taken orally or by injection. It is currently being studied as an augmentative substance to protect the cells from the cytotoxic effects of chemotherapy agents. In studies with mice treated with 5=Fluorouracil, lentinans increased production of stem cells and assisted elxogenous erythropoietin in relieving anemia (Takatsuki, 1996). The results from these studies are exciting and with time will produce results that are comparable to current chemotherapy in the future. However this does not mean all the herbs out there for cancer are working, in fact some have been shown to be outright fraudulent and sometimes fatal. Patients should be wary of the following herbs. The Hoxsey herbal treatment was developed by Harry Hoxsey and consists of an external and internal component. The external component consists of consuming various herbs as well as arsenic sulfide, which is so corrosive that it can destroy any body tissue on contact. The internal formula consists of about nine herbs, including cascara, which can serve as a laxative. Because of constant pressure by the FDA Hoxsey moved his treatment plan to Tijuana Mexico, where it is called The Bio-Medical Center. Peer-reviewed scientific literature and case history submissions by Hoxsey provided no acceptable evidence that his formula was effective (American Cancer Society, 1993). Mildred Nelson RN, Hoxsey's former head nurse now runs the Bio-Medical Center. Ironically, Hoxsey died of prostate cancer, apparently his own formula did not work for him (Castleman, 1991). Kombucha tea is derived from the fermentation of various yeast and bacteria. A starter culture is added to a mixture of black tea and sugar and allowed to ferment for a week or more. Kombucha tea can contain up to 1.5-% alcohol and a variety of other metabolites, such as ethyl acetate, acetic acid, and lactate. The tea must be stored properly because the acid could leach lead and other toxic elements form certain containers especially ceramic and lead crystal. Home brewed versions of this tea are prone to microbiologic contamination (Stone, 1995). Thus far all cancer claims are unsubstantiated (Boik, 1996). In fact daily drinking may be linked to acidosis and cardiac arrest, especially for those with preexisting health problems MMwr, 1995). Laetrile or amygdalin is a cyanogenetic glycoside found in the seeds of apricots, peaches and plums. It has been a popular cancer treatment since the 1920's. However studies done from the 1950's to studies done in the 1990's have failed to show any clinical value in the treatment of cancer, and no significant improvements in quality of life or symptom relief was seen (Moertel et al., 1982). Several case reports have described serious lethal toxicity from laetrile ingestion. Cyanide poisoning appears to be a risk only when taken orally because beta-glucosidase made by intestinal bacteria converts amygdalin to cyanide (American Cancer Society, 1996). It is currently used in many Mexican cancer clinics, and is illegal in 30 states in the United States. While there are some lethal and fraudulent claims being made by herbalists, there are many patients who claim these herbs work for them regardless of what has been scientifically proven. As physicians we must not turn our cheek in response to these methodologies. In fact a successful promoter of such therapies in the 1950's said, "Cancer victims come to us because they are unwilling to accept as final a death sentence handed them by their own doctors." (Lerner and Beckhardt, 1997) Even when there is no longer any effective treatment- the fundamental responsibility of caring for the patient is relieving any physical or emotional suffering. Anything less would be abandonment. Besides preventing abandonment, a physician must maintain good doctor/patient dialogue. Patients' report that 35% of the time, they do not discuss the option of alternative cancer treatment at all with their physicians. In addition most patients raise the issue of questionable practices after they have already committed to using them. Therefore a physician should take the initiative in this area and introduce the subject early on in the discussion of the cancer problem and it ramifications (Lerner and Beckhardt, 1997). A good opening for this subject would be, "In addition to the common Western medical treatment modalities that we have discussed, you very likely will hear about a variety of alternative treatments. I want you to know that I am available to discuss such proposals with you and can give you a scientific viewpoint to the treatment. I will not judge you for any decision you make for your health. However I would like to know what other forms of treatment you decide to use in order to pay attention to any interactions that may come from the use of the alternative treatment." This establishes that this information is acceptable for discussion between doctor and patient and that the patient should not be embarrassed to raise the subject. It also invites the patient to consult with a scientifically trained professional before the patient has committed to alternative treatment practice. The art in these dialogues is to help the patient appreciate the level of scientific credibility, if any, for a particular herb and any medical risks associated with the treatment. In order for this to work, doctors must commit themselves to effective patient education. Studies indicate that physicians consistently underestimate the patients' desire for complete medical information and they consistently overestimate the amount of time that they devote to patient education. A physician should be able to explain clearly and briefly how the safety and efficacy of a new treatment is established in clinical trials that are scientifically designed to ensure reproducible findings, finding the biochemical mechanism and getting FDA approval. Similarly, physicians should help patients evaluate claims made about various treatment options and to recognize fallacies of certain techniques that are used to promote questionable treatments. In order to reduce the confusion for patients, physicians should be familiar with resources available to them and their patients about all types of alternative treatments. This has proven to be a hard task. It appears physicians do not recognize useful sources of information and all too often simply have expressed disapproval without an interest in obtaining information. One of the best resources is the local chapter of the American Cancer Society. In addition to literature about alternative medicine practices, they can direct physicians to experts, locally, or nationally who are available to discuss a particular treatment with them or their patient. Other good sources include the American Society of Clinical Oncology, the FDA, the National Cancer Institute, and the United States Pharmacopoeia. Since many of these herbs are given in the context of cultural or religious beliefs it would be wise to consult a practitioner who is familiar with the patient's belief system. This ensures a team care approach to the patient while they go through this difficult time in their life.

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