The regular consumption of fish-oil has a potentially favourable role in inflammation, carcinogenesis inhibition and cancer outcomes. An analysis of the literature aimed to review the evidence for the roles of dietary-fish and fish-oil intake in prostate-cancer (PC) risk, aggressiveness and mortality.
A systematic-review, following PRISMA guidelines was conducted. PubMed, MEDLINE and Embase were searched to explore PC-risk, aggressiveness and mortality associated with dietary-fish and fish-oil intake. 37 studies were selected.
A total of 37-studies with 495,321 participants were analysed. They revealed various relationships regarding PC-risk (n = 31), aggressiveness (n = 8) and mortality (n = 3). Overall, 10 studies considering PC-risk found significant inverse trends with fish and fish-oil intake. One found a dose–response relationship whereas greater intake of long-chain-polyunsaturated fatty acids increased risk of PC when considering crude odds-ratios [OR: 1.36 (95% CI: 0.99–1.86); p = 0.014]. Three studies addressing aggressiveness identified significant positive relationships with reduced risk of aggressive cancer when considering the greatest intake of total fish [OR 0.56 (95% CI 0.37–0.86)], dark fish and shellfish-meat (p < 0.0001), EPA (p = 0.03) and DHA (p = 0.04). Three studies investigating fish consumption and PC-mortality identified a significantly reduced risk. Multivariate-OR (95% CI) were 0.9 (0.6–1.7), 0.12 (0.05–0.32) and 0.52 (0.30–0.91) at highest fish intakes.
The authors concluded that fish and fish-oil do not show consistent roles in reducing PC incidence, aggressiveness and mortality. Results suggest that the specific fish type and the fish-oil ratio must be considered. Findings suggest the need for large intervention randomised placebo-controlled trials.
Several other recent reviews have also generated encouraging evidence, e.g.:
Available evidence is suggestive, but currently inadequate, to support the hypothesis that n-3 PUFAs protect against skin malignancy.
…omega-3 fatty acids may exert their anticancer actions by influencing multiple targets implicated in various stages of cancer development, including cell proliferation, cell survival, angiogenesis, inflammation, metastasis and epigenetic abnormalities that are crucial to the onset and progression of cancer.
If I was aiming for a career as a cancer quack, I would now use this evidence to promote my very own cancer prevention and treatment diet. As I have no such ambitions, I should tell you that regular fish oil consumption is no way to treat cancer. It also is no way to prevent cancer. If anything, it might turn out to be a way of slightly reducing the risk of certain cancers. To be sure, we need a lot more research, and once we have it, fish oil will be entirely mainstream. Raising false hopes regarding ‘alternative cancer cures’ based on fairly preliminary evidence is counter-productive, unethical and irresponsible.
A lengthy article posted by THE HOMEOPATHIC COLLEGE recently advocated treating cancer with homeopathy. Since I doubt that many readers access this publication, I take the liberty of reproducing here their (also fairly lengthy) CONCLUSIONS in full:
Laboratory studies in vitro and in vivo show that homeopathic drugs, in addition to having the capacity to reduce the size of tumors and to induce apoptosis, can induce protective and restorative effects. Additionally homeopathic treatment has shown effects when used as a complementary therapy for the effects of conventional cancer treatment. This confirms observations from our own clinical experience as well as that of others that when suitable remedies are selected according to individual indications as well as according to pathology and to cell-line indications and administered in the appropriate doses according to the standard principles of homeopathic posology, homeopathic treatment of cancer can be a highly effective therapy for all kinds of cancers and leukemia as well as for the harmful side effects of conventional treatment. More research is needed to corroborate these clinical observations.
Homeopathy over almost two decades of its existence has developed more than four hundred remedies for cancer treatment. Only a small fraction have been subjected to scientific study so far. More homeopathic remedies need to be studied to establish if they have any significant action in cancer. Undoubtedly the next big step in homeopathic cancer research must be multiple comprehensive double-blinded, placebo-controlled, randomized clinical trials. To assess the effect of homeopathic treatment in clinical settings, volunteer adult patients who prefer to try homeopathic treatment instead of conventional therapy could be recruited, especially in cases for which no conventional therapy has been shown to be effective.
Many of the researchers conducting studies — cited here but not discussed — on the growing interest in homeopathic cancer treatment have observed that patients are driving the demand for access to homeopathic and other alternative modes of cancer treatment. So long as existing cancer treatment is fraught with danger and low efficacy, it is urgent that the research on and the provision of quality homeopathic cancer treatment be made available for those who wish to try it.
When I report about nonsense like that, I find it hard not to go into a fuming rage. But doing that would not be very constructive – so let me instead highlight (in random order) eight simple techniques that seem to be so common when unsubstantiated claims are being promoted for alternative treatments:
1) cherry pick the data
2) use all sorts of ‘evidence’ regardless how flimsy or irrelevant it might be
3) give yourself the flair of being highly scientific and totally impartial
4) point out how dangerous and ineffective all the conventional treatments are
5) do not shy away from overt lies
6) do not forget to stress that the science is in full agreement with your exhaustive clinical experience
7) stress that patients want what you are offering
8) ignore the biological plausibility of the underlying concepts
Provided we adhere to these simple rules, we can convince the unsuspecting public of just about anything – even of the notion that homeopathy is a cure for cancer!
Rudolf Steiner was a weird guy by any stretch of imagination. He was the founding father of anthroposophy, an esoteric “philosophy” that created a new dimension of obtrusiveness. Not only that, he also dabbled in farming methods, devised an educational technique and created an entire school of health care, called anthroposophical medicine. The leading product in its range of homeopathy-inspired “drugs” is a mistletoe-extract which is, according to Steiner, a cure for cancer. His idea was simple: the mistletoe plant is a parasite that lives off host trees sapping its resources until, eventually, it might even kill its host – just like cancer threatening the life of a human being!!!
So, what is more logical than to postulate that extracts from mistletoe are a cure for cancer? Medicine seems simple – particularly, if you do not understand the first thing about it!
But here comes the odd thing: some ingredients from mistletoe do actually have anti-cancer properties. So, was the old Steiner an intuitive genius who somehow sensed that mistletoe would be a life-saver for cancer patients? Or is all this just pure luck? Or was it perhaps predictable?
Many plants produce molecules that are so toxic that they can kill (cancer) cells, and many conventional cancer drugs were originally derived from plants; the fact that mistletoe has some anti-cancer activity therefore comes as a surprise only to those who have little or no knowledge of phyto-pharmacology.
Ok, mistletoe might have some ingredients which possess pharmacological activity. But to claim that it is a cancer cure is still a huge leap of faith. This fact did not stop promoters of anthroposophical medicine to do just that.
Due to decades of clever promotion, it is now hard in many countries (including for instance Germany) to find cancer patients who have not tried mistletoe; indeed, selling mistletoe preparations to desperate cancer patients has become a mega-business.
But does it actually work? Do these extracts achieve what proponents advertise?
The claims for mistletoe are essentially twofold:
1) Mistletoe cures cancer.
2) Mistletoe improves the quality of life (QoL) of cancer patients.
The crucial question clearly is: are these claims based on good evidence?
According to our own systematic review, the answer is NO. In 2003, we looked at all the clinical trials and demonstrated that some of the weaker studies implied benefits of mistletoe extracts, particularly in terms of quality of life. None of the methodologically stronger trials exhibited efficacy in terms of quality of life, survival or other outcome measures. The current Cochrane review (of which I am not a co-author) concluded similarly : The evidence from RCTs to support the view that the application of mistletoe extracts has impact on survival or leads to an improved ability to fight cancer or to withstand anticancer treatments is weak.
But both reviews have one major weakness: they included all of the many available extracts of mistletoe – and one cannot deny that there are considerable differences between them. The market leader in this area is Weleda (avid readers of science blogs might remember that this firm has been mentioned before); they produce ISCADOR, the mistletoe extract that has been tested more than any other such preparation.
Perhaps it would be informative to focus specifically on this product then? A German team from the “Center for Integrative Medicine, Faculty of Health, University of Witten/Herdecke” has done just that; despite the fact that these authors are not really known for their critical analyses of anthroposophical medicine, their conclusion is also cautious: The analyzed studies give some evidence that Iscador treatment might have beneficial short-time effects on QoL-associated dimensions and psychosomatic self-regulation.
So, what is the bottom line? Sceptics would say that almost a century of research without a solid proof of efficacy is well and truly enough; one should now call it a day. Proponents of mistletoe treatment, however, insist: we need more and better studies. Well, there is more! A new RCT of Iscador has just been published.
It included chemotherapy-naive advanced non-small-cell lung cancer (NSCLC) patients to assess Iscador’s influence on chemotherapy-related adverse-effects and QoL. Patients with advanced NSCLC were randomised to receive chemotherapy alone or chemotherapy plus Iscador thrice weekly until tumour progression. Chemotherapy consisted of 21-day cycles of carboplatin combined with gemcitabine or pemetrexed. Seventy-two patients were enrolled of whom 65% were in stage IV, and 62% had squamous histology. Median overall survival in both groups was 11 months. Median time to tumour progression was not significantly different between the two groups. Differences in grade 3-4 haematological toxicity were not significant, but more control patients had chemotherapy dose reductions, grade 3-4 non-haematological toxicities, and hospitalisations.
The authors’ conclusion: No effect of Iscador could be found on quality of life or total adverse events. Nevertheless, chemotherapy dose reductions, severe non-haematological side-effects and hospitalisations were less frequent in patients treated with Iscador, warranting further investigation of Iscador as a modifier of chemotherapy-related toxicity.
So, does Steiner’s notion based on the weirdest of intuitions contain some kernel of truth? I am not sure. But for once I do agree with the proponents of mistletoe: we need more and better research to find out.
Since weeks I have been searching for new (2013) studies which actually report POSITIVE results. I like good news as much as the next man but, in my line of business, it seems awfully hard to come by. Therefore I am all the more delighted to present these two new articles to my readers.
The first study is a randomized trial with patients suffering from metastatic cancer who received one of three interventions: massage therapy, no-touch intervention or usual care. Primary outcomes were pain, anxiety, and alertness; secondary outcomes were quality of life and sleep. The mean number of massage therapy sessions per patient was 2.8.
The results show significant improvement in the quality of life of the patients who received massage therapy after 1-week follow-up which was not observed in either of the other groups. Unfortunately, the difference was not sustained at 1 month. There were also trends towards improvement in pain and sleep of the patients after massage. No serious adverse events were noted.
The authors conclude that “providing therapeutic massage improves the quality of life at the end of life for patients and may be associated with further beneficial effects, such as improvement in pain and sleep quality. Larger randomized controlled trials are needed to substantiate these findings“.
The second study examined the effectiveness of a back massage for improving sleep quality in 60 postpartum women suffering from poor sleep. They were randomized to either the intervention or the control group. Participants in both groups received the same care except for the back massages. The intervention group received one 20-minutes back massage at the same time each evening for 5 consecutive days by a certified massage therapist. The outcome measure was the Pittsburgh Sleep Quality Index (PSQI). The results showed that the changes in mean PSQI were significantly lower in the intervention group than in controls indicating a positive effect of massage on sleep quality.
The authors’ conclusions were clear: “an intervention involving back massage in the postnatal period significantly improved the quality of sleep.”
Where I was trained (Germany), massage is not deemed to be an alternative but an entirely mainstream treatment. Despite this fact, there is precious little evidence to demonstrate that it is effective. Our own research has found encouraging evidence for a range of conditions, including autism, cancer palliation, constipation, DOMS and back pain. In addition, we have shown that massage is not entirely free of risks but that its potential for harm is very low (some might say that this was never in question but it is good to have a bit more solid evidence).
The new studies are, of course, not without flaws; this can hardly be expected in an area where logistical, financial and methodological problems abound. The fact that there are many different approaches to massage does not make things easier either. The new evidence is nevertheless encouraging and seems to suggest that massage has relaxing effects which are clinically relevant. In my view, massage is a therapy worth considering for more rigorous research.
Whenever I lecture on the topic of alternative medicine for cancer, the first comment from the audience usually is “aren’t there any herbal treatments that are effective?” This is of course a most reasonable question; after all, many conventional cancer drugs originate from the plant kingdom – think of Taxol, for instance.
My answer often upsets believers in alternative cancer remedies. I tell them that, no, there is none and, even worse, there never will be one.
Did I just contradict myself? Did I not just state that many cancer drugs come from plants? Yes, but once the pure ingredient is isolated and synthetized, the drug ceases to be an herbal remedy which is defined as an extract of all the plant’s ingredients, not just one isolated constituent.
And why am I so depressingly pessimistic about there ever being an herbal cancer cure? Because of a simple fact: as soon as a natural substance shows the slightest promise, scientists will analyse and test it. If this process turns out to be successful, we will have a new cancer drug – but not an effective herbal remedy. Again, think of Taxol.
Since almost a decade, colleagues and I have been working on a relatively little-known project called CAM cancer. It started as an EU-funded activity and is now coordinated by Norwegian researchers. Our main aim is to provide unbiased and reliable information about all sorts of alternative treatments for cancer.
Our team is large, hard-working, highly motivated and independent – we do not accept sponsorship from anyone who might want to influence the results of what we are publishing. It is probably fair to say that most individuals who give their time working for CAM cancer are more optimistic than I regarding the value of alternative treatments. Therefore, our publications are certainly not biased against them; if anything, they are a bit on the generous side.
Much of our work consists in generating rigorously researched and fully referenced summaries of the evidence. Before these get published, they are thoroughly peer-reviewed and, whenever necessary, they also get updated to include the newest data. A good proportion of the reviews relates to herbal treatments.
Here are the crucial bits from our conclusions about those herbal cancer remedies which we have so far investigated:
Aloe vera: …studies are too preliminary to tell whether it is effective.
Artemisia annua: …there is no evidence from clinical trials…
Black cohosh: …In all but one trial black cohosh extracts were not superior to placebo.
Boswellia: …No certain conclusions can be drawn…
Cannabis: …The use of cannabinoids for anorexia-cachexia-syndrome in advanced cancer is not supported by the evidence…
Carctol: … is not supported by evidence…
Chinese herbal medicine for pancreatic cancer: …the potential benefit… is not strong enough to support their use…
Curcumin: There is currently insufficient documentation to support the effectiveness and efficacy of curcumin for cancer…
Echinacea: …there is currently insufficient evidence to support or refute the claims… in relation to cancer management.
Essiac: There is no evidence from clinical trials to indicate that it is effective…
Garlic: Only a few clinical trials exist and their results are inconclusive.
Green tea: …the findings… are still inconclusive.
Milk vetch: Poor design and low quality… prohibit any definite conclusions.
Mistletoe: …the evidence to support these claims is weak.
Noni: …evidence on the proposed benefits in cancer patients is lacking…
PC-Spes: …the… contamination issues render these results meaningless. An improved PC-Spes2 preparation was evaluated in an uncontrolled study which did not confirm the encouraging results…
St John’s wort: …there are no clinical studies to show that St. John’s wort would change the natural history of any type of cancer…
Ukrain: …several limitations in the studies prevent any conclusion.
As you can see, so far, we have not identified a single herbal cancer treatment that demonstrably alters the natural history of cancer in a positive direction. To me, this suggests that my rather bold statements above might be correct.
Of course, there will be some enthusiasts who point out that the list is not complete; and they, of course, are correct: there are probably hundreds of herbal remedies that we have not yet dealt with. And, of course, for some of those the evidence might be more convincing – but somehow I doubt it; after all, we did try to tackle the most promising herbal remedies first.
My claim therefore stands: there never will be a herbal (or other alternative) cancer cure. But, please, feel free to convince me otherwise.