Complementary and alternative therapies for prostate cancer

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A cancer diagnosis is life-changing. Men with prostate cancer often react with determination, vowing to fight the disease by any means possible. Aside from mainstream medicine and surgery, there are many other therapies and lifestyle changes that claim to help prevent and treat prostate cancer. These interventions include complementary and alternative therapies. A US organisation called the National Cancer Institute have recently published extremely useful summaries of the scientific evidence surrounding many different complementary and alternative therapies for patients.

It's very common for someone diagnosed with cancer to be told by well-meaning friends that they know of treatments and cures that aren’t recommended by clinicians. But choosing a safe an effective complementary therapy can be very difficult. Different health professionals have very different opinions on the matter, and information from the internet is notoriously untrustworthy on this subject. This blog aims to provide information about the supply and regulation of complementary therapies in Australia, as well as some useful resources that summarise the scientific evidence regarding some of these therapies.

Mainstream, complementary and alternative therapies

Mainstream therapies generally refer to medications, surgery and procedures for which there is scientific evidence in favour of their effectiveness and safety in humans. Mainstream therapies are usually considered to be those in current use by doctors, as opposed to out-dated therapies that have better alternatives. Mainstream medicine is sometimes referred to as Western medicine or conventional medicine.

There are many different names that are used to refer to various non-mainstream therapies. These include complementary therapies, alternative therapies, integrative medicine, holistic or unconventional therapies. For the purposes of this article, we will group these under two headings that are commonly used:

Complementary medicine and therapies are used alongside mainstream therapies. They are used to improve the effectiveness of mainstream therapies, provide additional benefit, improve side effects or improve health in general. There is not enough scientific evidence to support the use of complimentary therapies as a way to treat cancer by themselves. If there was, these would be considered mainstream therapies. There are, however, some complimentary therapies for which there is good evidence that they provide additional benefit, when used alongside a mainstream therapy.

Alternative medicine and therapies are used instead of mainstream therapies. These are usually used to treat or prevent a condition, such as prostate cancer, or to improve health more generally. In some countries and cultures, traditional medicines such as herbal remedies, are very commonly used, and therefore may be considered mainstream for that culture. Herein, we refer to mainstream therapies as those considered mainstream in Australia.

Complementary and alternative therapies include a very wide range of medicines, treatments and procedures. Some examples are herbal medicine, meditation, supplements, massage, exercise, acupuncture and reiki. There is also a wide range of beliefs and reputations regarding these potential therapies. Complementary therapies such as tailored exercise programs have a good reputation and are often recommended by clinicians. Others, such as homeopathy, are widely believed to be ineffective (no more than a placebo effect), or even fraudulent.

So how can a man, who wants to do anything possible to fight his cancer, decide which complimentary therapies are worth trying?

Do complementary therapies work?

Since there are many different therapies aside from mainstream medicine, this is always going to be a complicated answer. Generally speaking, these therapies fall into 3 broad categories:

1. Therapies for which there is good evidence that they provide additional benefit, when used alongside mainstream therapies. One example is tailored exercise programs, which can reduce fatigue, improve bone strength and muscle mass.
2. Therapies that we know do not provide benefit, as demonstrated by definitive studies. We have good reason to believe that these don’t do what might be claimed. An example is vitamin E and selenium supplements for preventing prostate cancer. There is good evidence from a large randomised controlled trial that neither vitamin E nor selenium prevented prostate cancer in men when taken regularly.
3. Therapies that have not been adequately tested in clinical trials. These may or may not be effective. Most complementary therapies fit into this category. For this reason, it’s very difficult to answer the question – do they work? We simply do not have enough information to be sure of an answer to this question.

Clinicians usually make decisions on the basis of definitive evidence. This might be from well-conducted clinical trials, or from decades of documented use in our health systems. But the reality is that there are different levels of evidence. There are many instances where there is some evidence to support a therapy, but not enough to be sure. It’s difficult for clinicians to make recommendations, when the evidence is inconsistent or too preliminary. Unfortunately, this high standard is not always adhered to within various industries that advertise complementary and alternative medicines. Claims are often made about benefits in order to sell these products, which are not backed-up by an appropriate level of scientific evidence.

Are there harms in using a complementary therapy?

Using a therapy that has not been the subject of a randomised controlled trial (such as most complementary medicines) brings some risk. Clinical trials test not only the effectiveness of a therapy, they also test the safety and side effects. So for a therapy that has not been tested by men with prostate cancer in trials, we can’t be certain whether it:

- slows tumour growth

- makes the cancer worse

- has bad side effects

- improves sides and symptoms of the cancer

- makes other medications, such as chemotherapy, less effective

- has unlisted ingredients that may cause harm. An example is described in this research blog about supplements for treating erection problems.

Another potential harm is that complementary therapies can be very expensive. If they are not providing any benefit, then this money is wasted.

So there are potential harms that may occur when taking a complimentary medicine alongside mainstream treatments. But which ones are harmful and which ones are worth trying?

In reality, clinicians and allied health practitioners have some evidence on which to base their advice. For instance, there is much known about the safe doses, side effects and interactions of herbal medicines with other medications. This information is best sought from experienced and qualified clinicians rather than the websites selling the products. Complementary medicines sold in Australia are also regulated by the TGA, providing some assurance that they do not contain harmful ingredients (see below).

What does the science say?

A US organisation called the National Cancer Institute (NCI) have recently published extremely useful summaries of the scientific evidence surrounding many different complementary and alternative therapies for patients. Rather than reproduce this information here, the web links are provided below.

The NCI have a page dedicated to nutrition and dietary supplements that have been specifically tested for prostate cancer: https://www.ncbi.nlm.nih.gov/books/NBK83984/

The NCI also provides summaries of the evidence for many different complementary therapies for all cancers (not specifically prostate cancer). Much of this information is very useful for prostate cancer patients, such as therapies that relieve side effects during chemotherapy. These sites are listed under the heading “Integrative, alternative, and complementary therapies” at this website:

https://www.ncbi.nlm.nih.gov/books/NBK82221/

Some particularly useful links from this page describe:

Acupuncture

Cannabis

Gerson therapy

Vitamin C

There are many type of complimentary therapies for which the evidence is not yet discussed on the NCI webpages. We will try to cover the major ones in upcoming blogs over 2019.

Regulation of complementary medicines in Australia

All therapeutics sold in Australia should be subject to regulation by the therapeutic goods administration (TGA). These include prescription medicines, over-the-counter medicines, supplements, complementary medicines and some everyday items such as suncream. The TGA is responsible for ensuring that therapeutic goods available for supply in Australia are safe and fit for their intended purpose.

The TGA regulates therapeutic goods through:

• pre-market assessment
• post-market monitoring and enforcement of standards
• licensing of Australian manufacturers and verifying overseas manufacturers' compliance with the same standards as their Australian counterparts.

Medicines are approved by the TGA as either 'registered' (for higher risk) or 'listed' (for lower risk) before they may be supplied in Australia, unless exempted. Registered medicines are assessed for safety, quality and effectiveness. They include all prescription only medicines and many over-the-counter products such as those for pain relief, coughs and colds and antiseptic creams. Lower risk medicines are listed on the Australian Register of Therapeutic Goods. Listed medicines can only contain pre-approved low-risk ingredients. Listed products are only reviewed for safety and quality. They include sunscreens over SPF4 and many vitamin, mineral, herbal and homoeopathic products.

It’s important to note that most complementary medicines are listed, therefore the effectiveness of these products is not assessed by the TGA. These are marked as Aust-L on the packaging. Just because a product is listed by the TGA, does not mean that the TGA has assessed whether it does what is claimed on the packaging. If product is advertised as “TGA-approved”, you can check whether it is listed (effectiveness not assessed) or registered (effectiveness is assessed) by finding the Aust-L or Aust-R mark on the package.

More information about the regulation of complementary medicines by the TGA can be found here.

Where to buy complementary medicines in Australia?

Complementary medicines can be purchased from many different shops and usually don’t require a prescription. Complementary and prescription medicines can be bought over the internet from online pharmacies. There are legitimate online pharmacies that supply TGA-registered and listed goods within Australia. They supply prescription medicine when a prescription is sent to them. Unfortunately, there are also sources of medicines that are not regulated by the TGA, particularly international websites. It is illegal to import some medications into Australia. So ordering from these websites can bring trouble in many different ways. This NPS Medicinewise website has some useful advice for people wishing to order medications over the internet.

Are there harms in using an alternative therapy?

An alternative therapy is one that is not supported by clinical trial evidence, and that is used instead of mainstream therapies. Alternative therapies bring the potential for harm in two ways: from the therapy itself, and from the decision to forgo the mainstream therapy.

It’s rare to find people with cancer who forgo all mainstream therapies. It’s more common that people pick and choose between therapies, trying alternative therapies in between some mainstream therapies. A delay in using a mainstream therapy whilst someone tries an alternative therapy could be harmful, if the alternative therapy fails and the cancer spreads before a mainstream therapy is used.

Alternative and complimentary therapies are usually advertised on websites that provide a lot of personal testimonies. These are short description from “patients” who claim to have benefitted from these therapies. Although these might sound very convincing, it’s difficult to be sure of their accuracy.

A more scientific approach was used by a group of researchers from the Yale School of Medicine in the US. They identified people who had forgone all mainstream cancer treatments after their diagnosis, using the National Cancer Database records in the US. The people they studied were diagnosed with prostate, lung, breast or colorectal cancer between 2004 and 2013. They only studied people diagnosed with cancer that had not spread (non-metastatic).

The Yale researchers found records of 281 people who were diagnosed with one of these cancers and chose alternative therapies rather than any mainstream therapies. These people were compared to patients with very similar characteristics who chose mainstream therapies. The results showed that:

People who chose alternative therapies were significantly more likely to die in the follow-up time period (until 2017), than those who used mainstream therapies. People choosing the alternative therapies were 2.5 times more likely to die during the study follow-up than those who did not. Differences could be seen for each of the four cancers tested. Whether these people were harmed by the therapy they chose or harmed by their choice to forgo all mainstream therapies, was not examined in the study. These results indicate that there are harms for choosing alternative therapies over mainstream therapies for treatment of these four cancers.

Complementary therapies to improve quality-of-life

In the past, clinical trials for prostate cancer treatments have mainly concentrated on effectiveness and safety. Effectiveness is usually measured as living longer, or a delay to disease progression. However, living longer is not the same as living well. More recently, the quality-of-life for a man being treated for prostate cancer has become an important outcome measured in clinical trials. Researchers and doctors have a much better appreciation of the importance of quality-of-life for these men.

A complementary therapy can improve quality-of-life, even if it does not improve how long a man lives, or how long until disease progression. If using complementary therapies makes a man feel better, and improves his quality-of-life, then it has done something to help. But this is provided there are no unintended effects such as decreasing the effects of other medications. Complementary therapies such as exercise, massage, meditation, yoga, and acupuncture may not change the course of a man’s disease, but they may make him feel better. These interventions might help him cope with the physical and emotional challenges of living with cancer. By improving his quality-of-life, they have done something valuable for him.

PCFA recommends speaking with your healthcare team if you are thinking of using a complementary therapy to make sure they are safe and won’t interfere with any of your other treatments.