Vitamins and herbs may reduce the cure rate of cancer therapy

Dr. Andrew Dean – OncologistMBChB MRCP(UK) FRACPMedical Director and Founder of Virtual Cancer Centre and Virtual Medical CentreOne of my colleagues has a reputation for being extremely intolerant of anyone taking anything other than his prescribed medication. Rumour has it that he has thrown down his pen in the midst of a consultation when one of his patients dared to inquire about vitamin C injections or a herbal supplement. I, on the other hand, have a reputation for being “a bit soft”. I am supposedly very tolerant of patients wishing to experiment with herbal remedies etc. However, in the light of recent media publicity, I have to concede that he could well be right; recent newspaper articles have quoted a new far-reaching study, which shows that people who take vitamin supplements have a lower life expectancy than people who don’t.1 This has attracted more attention than previous studies, which showed that lung cancer patients being given supplemental vitamins A, C and E all experienced recurrence of their cancer sooner, which progressed more rapidly resulting in a sooner death.2 Both studies in fact, one in the US and one in Scandinavia, had to be stopped early because of the enormity of the difference between the vitamin supplemented and the non-vitamin supplemented group. Why then was this study not given any attention?

Vitamins and cell growth

The word vitamin came from the amalgamation of two words; vital and amines. These were supposedly chemicals that the body was unable to manufacture itself and thus it was vital that these were ingested. It is understood that generally, vitamins are necessary for normal metabolism, cell growth and tissue repair. It may seem logical therefore that a gross excess of vitamins could encourage cell growth and division in the cells in which we least want it (i.e. cancer cells). As oncologists, we try frantically to arrest cancer cell growth, yet ironically by not taking a stand against vitamin supplementation, we may be letting our patients, and ourselves down. By taking vitamin supplements, our patients may unknowingly be stimulating the growth and proliferation of the very cancer cells that we are trying to kill.

That is not to say that in certain circumstances careful supplementation of certain vitamins is not helpful. A typical example would be therapy with Pemetrexed (Alimta) with which vitamin supplementation with folic acid and vitamin B12 has been shown to reduce side effects of chemotherapy and improve quality of life.³ This does not mean however that blanket supplementation with these vitamins should encouraged for everyone. The difference here is that there is a significant scientific basis for supplementation with these vitamins. Another example would be the addition of folinic acid to 5FU chemotherapy. It is known that the Folinic acid significantly improves the response rate to chemotherapy with this agent.⁴ Again there is a significant scientific basis for its use. 
 
The case against health supplements

Certain cancer treatments rely upon the creation of free radicals to damage the DNA of cancer cells. Primarily of course I am talking about radiotherapy. Radiotherapy involves high-energy proton or electron beams, beamed directly at cancer cells in an effort to damage their DNA. Often they do so by the creation of toxic free radicals within the affected tissues, which then cause the damage to kill the cancer cell. Using free radical scavengers such as vitamins C and E potentially reduces the creation of the free radicals and possibly decreases the effect of radiotherapy. Should radiation oncologists therefore be more vigilant about what supplements their patients are taking?

It is likely, that if patients are taking vitamin supplements, they are taking them to excess. It is known that excess vitamins can be harmful in themselves, regardless of whether the patient has cancer. Three examples would be hypervitaminosis A in which patients can suffer marked cutaneous and metabolic problems with excess doses of vitamin A. A vitamin A derivative, Beta-carotene, has been shown to worsen the outcome in patients with mesothelioma and lung cancer.⁵ Excess vitamin D consumption (e.g. eating polar bear liver) can be rapidly fatal due to hypervitaminosis D. Happily, not many oncology patients eat polar bear…(!) Excess doses of vitamin C have been known to cause inflammation of the kidneys, interstitial nephritis.⁶ The purveyors of the Emperor’s new clothes would however encourage cancer patients (as indeed they do) to have high doses of intravenous vitamin C to “boost the immune system”. The charge to the patient is often ten times the cost of the vitamin C ampoule. 

How many times per day do Oncologists get asked “is it alright for me to take these doctor?” Often these are obscure herbal remedies or mixtures of herbs and usually from the Asian subcontinent. Are they harmful? Who knows? In fact, what evidence is there of quality control or even accurate knowledge of what the herbal preparations contain? There are many reports of lead and other heavy metal poisoning from herbal and mineral supplementation.⁷ Are herbs necessarily harmless? One of the countries most widely consumed herbal remedies, St John’s Wort, is know to interact with virtually every prescription drug. It interacts with the enzymes that are responsible for drug metabolism and although there is no doubt that St John’s Wort works reasonably well as an antidepressant; its use would be strongly cautioned in anyone who is taking any prescription medications.⁸ So what then if patients are on chemotherapy? Well herbal remedies are potentially anything but harmless. If they induce the body’s enzymes (i.e. make the body metabolise substances more efficiently) then it is possible that this reduces the levels of circulating chemotherapy. It is known that chemotherapy levels are very important in determining optimal cell damage. Reduction of the effective chemotherapy dose can therefore reduce cancer cell death, potentially reducing the response and cure rate to the chemotherapy. If the herbal supplements reduce the activity of liver enzymes, this could raise the chemotherapy levels, which could in turn be toxic. If we tell patients that “its OK to take herbal supplements” could we then be guilty of malpractice i.e. in advertently misleading our patients into doing themselves harm by taking drugs which will interfere with the prescribed anticancer therapy. 

Unproven therapies 

A number of doctors have now joined a group called the Australian College of Nutritional and Environmental Medicine, practicing full-time with alternative and unproven remedies. Does the fact that they have their own college actually give credibility to potentially harmful therapies? Should doctors who in theory abide by the Hippocratic oath, prescribe medications without any scientific validity? The medical history books are full of well meaning practitioners who passionately believed in a pathological or therapeutic theory. Researchers have even gone so far as to inject themselves with the HIV virus because they passionately believe that the retrovirus itself was not the cause of AIDS. Passionate belief does not necessarily equate to therapeutic efficiency. The only way we find if treatments work is through rigorous controlled scientific trials that make a fair assessment of the probability of chance affecting the results. 

So is mainstream medicine guilty of passive acceptance of a small group of colleagues use of unproven (and should this read potentially harmful?) therapies? Unproven therapies mean that there is no evidence that the therapy works. Why therefore would anyone in their right mind either want to take it or encourage patients to take it? 

One medical practitioner, who practices heavily in this field, is known to charge large sums of money to people who can least afford it i.e. patients who have been afflicted by cancer, who are no longer able to work, who are facing death. These patients are often paying large sums of money in the hope that they may benefit from these unproven remedies. The ethics of this are surely questionable? 

Most of us in Oncology have seen repeated vogues in cycles of usually a few years. Shark cartilage was first touted as a cure for cancer back in the 1960’s. When it was shown not be of any use, it died a death only to resurface in the 1990’s. Virtually every single cancer patient coming to the clinic was taking Shark cartilage and unfortunately none of them have seemed to benefit. The “scientific” theory underpinning is that no shark has ever been discovered to have cancer.⁹ Call me skeptical, but to my recollection, sharks that die from cancer would tend to be eaten by their mates or sink to the floor as they have no air bladder to keep them afloat. Why would consumption of an inner substance such as cartilage, be expected to be absorbed by the human body and turn into a miracle cancer cure? Another well meaning and passionate theory is that the antihistamine Promethazine gets into cancer cell mitochondria and poisons their metabolism thus killing the cancer cells.¹⁰ At various times over the last 15 years, patients have arrived for their oncology appointment in semi-comatosed states, wheeled in by relatives in wheelchairs, causing alarm on behalf of the treating doctors. Has the patient taken an expected deterioration? Is the patient about to die? Am I poisoning the patient with too much painkiller? The answer is NO! The patient is doing the latest cancer treatment fad, taking large doses of Promethazine. Boy, what an improvement in quality of life?…I don’t think so.

Recently, the Cancer Support Association of WA sponsored a public evening in which a European oncologist, who is barred from practicing in their home country, gave a theory about using intravenous sodium bicarbonate as a cancer treatment. Patients flocked to the purveyor’s of the Emperors New Clothes, spending hundreds of dollars with colleagues who have no specialist training, colleagues who are only too happy to dispense intravenous sodium bicarbonate (at quite a high price too actually). 

Hope

What then is the role of hope in cancer care? An excellent nursing paper addressed this. It recalled the story of Pandora’s box. Pandora, driven by curiosity, opened the forbidden box. Out of the box rushed all the evils of the world, anger, greed, despair, envy, sloth etc but remaining in the bottom of the box was hope. Thus the question as to the nature of hope arose. Was hope the greatest evil in the world or was it actually the antidote to all the evils in the world? 

We all see hope as being essentially to the human condition. Patients, who have hope, are generally more upbeat and have better quality of lives than those whose lives are devoid of hope. But what is important is that the hope is kept grounded and realistic. When a patient gets a lump, they hope it’s not cancer. When that hope is dashed, it is important that that hope is replaced with something else. i.e. the hope that the cancer can be cured. When surgery and other treatments take place, the patient hopes they are cured. We hope they are cured. If however they relapse, it is important that the germ of hope is kept alive i.e. it may not be possible to cure it but we can give some treatment which may shrivel it down and put you in remission. The problem comes when the hope is unrealistic and preyed upon by the purveyor’s of Emperor’s New Clothes. Rather than encourage the hope that patients may enjoy the best quality of life their remaining time, certain practitioners encourage patients, often impoverished by their illness, to spend what money they can’t afford on an unproven remedy.

What therefore is the responsibility of the general medical community? Should the general medical community make official complaints to the medical board in each state about medical practitioners who carry out unproven, potentially dangerous and usually expensive treatments? Should the Minister of Health on behalf of the government, take action to prevent people being preyed upon? Should the government legislate that alternative and unproven remedies carry health warnings such as “warning, unproven remedies may do nothing at all” or “warning, these herbs can make you ill”.

References

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10. Jones GR. Successful cancer therapy with promethazine: the rationale. Med Hypotheses. 1996 Jan;46(1):25-9.