Is Cannabis a Cure for Cancer?

I wrote this blog about half a year ago when I worked in a forensic drug laboratory, although I have updated it as I have found information over the last few months. Whilst reasearching something for a project I came across two things: a claim of the increase in THC content by 30 fold and a claim that that smoking cannabis or ingesting 'hash oil', will indeed cure cancer. A little look into those two pretty much showed them to be pseudo-scientific bullcrap. And here is why:

How pure can we get?

“Cannabis is 30x more potent today than it was in the 60’s”

This statement was on more-or-less every single website I had looked on, more so the websites supporting the legalisation of cannabis. It even worked itself into the popular media, gaining its own article in The Independent. The article kindly apologises for it’s backing of the legislation to legalise the drug. However, after reading some ‘statistics’ saying cannabis is 25x stronger than it was at Woodstock, they have ‘reversed their landmark campaign for decimalisation’. A high portion of the websites found when looking at the quote, were those that had forums detailing the cultivation and selling of flowering material, none of which, had a reference or any indication of study to say that the potency had increased 30 fold during the past 40-50 years. Where to start? Is the increase that of an overall average of all the strains of cannabis or just one common strain? Rosenthal has books detailing the breeds of cannabis, for which they give vast information on over 200 popular strains of cannabis. So there’s a start, did they test over 200 breeds of cannabis for their potency? In short: probably not, as that is ridiculously unfeasible.

A systematic review and meta-analysis shows that there is an increase in the measured THC content over the years. I suppose, it would be right in saying, from this study that the potency appears to have increased by around 5 fold, most likely due to more widespread testing. However, with that said, the data could be skewed due to the different types of cannabis itself, the methods it has been grown, the freshness, the packaging, storage, humidity, and genetic features of the plant all effect THC content. The review takes studies from around the world and collates the information, meaning all the factors above have a great influence on the purity, for instance THC content correlated with plants that are grown outdoors in other countries are collated with the strains grown indoor in the UK. Segregating this difference doesn’t appear to have been addressed in the review. It also shows purity as low as 0.4% in 1976 and goes on to say that the purities now are much higher. 0.4% appears to be the lowest recorded, from that the study chose to compare the lowest to the highest, and use that to make their conclusions. This study showed the trend of cannabis potency in the US over 7 years (1980-1997) showing that potency appears to have steadily increased 3 fold from an average of 1.5% in 1980 to 4.8% in 1997.

So why are people claiming a 30 fold increase? Simply because they can, as mentioned, this is done by comparing the lowest THC content of cannabis with the highest. To reiterate Ben Goldacres excellent take on this: Ronald Reagan’s war on drugs, in the 80’s, was propagated with a claim that cannabis was 14x stronger than in 70’s. So, if it was 14x stronger in the mid 80s than in the 70’s, and it is 30x stronger today …is it actually 420x stronger than in the 70s? That requires more THC than actual plant matter, which is, obviously, impossible. The available data doesn’t show any ridiculously large upward trend in the potency of cannabis. The claims made about the strength of cannabis are not supported by the limited amount of data available. To determine the average potency levels of cannabis properly; researchers need to examine a cross section of cannabis plants, unfortunately, from the data I can find, that wasn’t done in the 60/70’s. For this reason, it is not possible to make accurate comparisons of data between the THC levels 40-50 years ago and the THC levels of today.

Cancer is the enemy, but is cannabis the remedy?

Another peculiar claim pertaining to cannabis is that ‘Cannabis Cures Cancer’. Mostly, it is from people just randomly claiming that cannabis cures cancer, with no actual, real information. Digging around yielded little information on the ‘facts’ themselves. Cannabis’ effect in reducing nausea in chemotherapy has had negative results and some positive results in different clinical trials. Obviously, this is after treatment of cancer, nothing to do with the curing or the prevention of the disease. Cancer, unfortunately, is ridiculously diverse, with cancer research stating there are over 200 different types of cancer. Each of which have different genetics, causes, prognoses, pathology etc., so, it is not a disease with one unified treatment course, its like coming up with one unified course for all infections.

Scouring the Internet, I found very little showing a coherent study with conclusive results. There may not be enough studies or studies of a high quality enough to produce a coherent systematic review. A review summarising current knowledge’s of the ‘anti-tumour’ potential of cannabis in breast cancer, suggesting that cannabinoid based medicines may be useful in treating most breast tumours. To most people, that would imply smoking cannabis is going to cure breast cancer. Well, it simply won’t. The preliminary studies are carried out in cell cultures, not clinical trials. Furthermore, it states that the active ingredients must be delivered to the site of the tumour in the correct dosage to cause cell apoptosis, that is, to kill the cancer cells. Smoking or consuming cannabis would never produce a THC level high enough to kill the cancer at the site. Another study once again shows that cannabidol shows a chemo preventive effect on the colon cells. Where? In human trials? No, in a cell culture, of course. The only difference between this and Caffarel (previous) is that it doesn’t describe a dose-response relationship.

 

I have seen opposing arguments saying cannabis isn’t used as treatment because of its’ health effects and a massive government conspiracy to cover up the studies, no, I am not joking. Compared to all the cancer research going on currently, cannabis, as anti-cancer research is very minute. However, this isn’t exactly unusual because more research is plied into more promising compounds with respect to anti-cancer properties is larger because of the clinical success being larger. There is only one clinical trial that I have found. The study (described here) was a phase 1 clinical trial that has gone no further. There is very little convincing evidence on this paper, as there were only nine patients. These results could be consistent with an anti-tumour effect as well as being easily consistent with no effect. Even in this study, the subjects had catheters poked into the site of the tumour, so the THC was being placed directly onto the tumour. It is a direct contact with the tumour site, infusing THC into the brain cavity where the tumour had been, not being smoked.

Conclusion

So, is cannabis really a cure for cancer? Research suggests ‘there isn’t enough evidence to make that claim’. Quite frankly, to me, it is clear it doesn’t cure cancer, at least not on its own and definitely not if smoked. There is some interesting research in the role of cannabinoid receptors acting on cancer and if targeting them with agonists of cannabinoids is useful in terms of anti-cancer therapies (see above). This website shows a stunning amount of trials with the use of cannabinoids to treat the side effects of actual cancer treatments but few to actually treat cancer in itself. As I said, I’ve read of arguments of big pharma and the government hiding the research that shows how amazing cannabis is as a cure for cancer because cannabis is bad, and you shouldn’t do drugs. Big pharma also wants to supress research that would make them billions? Furthermore, if the motive (and let’s be clear, from what I can tell, most of the people arguing this haven’t studied any aspects of science) is to make cannabis legal, that is fine (arguably) to argue, trying to claim that cannabis has medical value, not based on any real science however, is not. Claiming that pharmaceutical companies will lose money on making drugs is a ridiculous claim. Pharmaceutical companies aren't stupid, and they are quick to jump on the avenues for effective treatment therapies. There are always ways to repackage and patent molecules, no matter what they are, which would give them a return on the investment required to develop and test them in clinical trials. To suggest that the cure is being hidden with literally no evidence, is not only ridiculous on the face of it but it’s offensive to the community of dedicated, ridiculously hardworking scientists, to the staff and supporters of cancer research to cancer patients and their families.

A blog to check out for quackery of this ilk is ‘Truth Activist’. A particular article entitled: ‘There is no mistaking it, cannabis cures cancer’. When they aren’t spreading conspiracy theory nonsense, mainly pertaining to the ‘truth’ about 9/11, they feel they need to have a hand in at ‘science’ with their ‘wellrespected’ TV personality doctors. Their published blogs tend to links their sources to forums, using people with usernames like ‘loveweed2k14’, claiming that their mums cats brothers friends dolphin had a bong hit and his cancer was cured, and using that as ‘evidence’. A collection of studies have been very carefully cherry picked to prove that cannabis cures cancer here. However, even more meticulous and well researched is the debunking of each and every single one of those 20 papers by someone who knows what they are talking about here. Check it out kids, and remember, just because it is written down, doesn't mean it's true.