Category: Cancer

Over the years there has been a lot of tomato talk, about how lycopene, the red pigment found in this fruit (yes, it’s definitely a fruit, it’s got seeds), could ward off cancer, specifically prostate cancer. It has also been linked to protecting us from cardiovascular disease, per the common discussions about the so-called Mediterranean diet. It is not a panacea and tests and trials have been small-scale. Nevertheless, as with the likes of that other infamous compound, resveratrol found in red wine, researchers are keen to demonstrate a link with their particular natural chemical and disease prevention.

In the first June issue of SpectroscopyNOW I discuss tests on lycopene extracted from tomatoes that seem to show it offers a certain level of protection against liver cancer triggered by nitrosamines, in lab mice at least. Ashwani Koul and his colleagues at Panjab University in Chandigarh, India, have been doing the research with interesting results. I asked Koul about the impetus:

“Since time immemorial, the tomato has formed an integral component of food, both traditional and western form,” he told Sciencebase. “It is used widely as a vegetable and is abundantly used in the preparation of sauces, curry, soup etc. throughout the world. Epidemiological studies indicate that populations consuming high amounts of vegetables including tomato, in their diet have a reduced incidence of several types of cancer.” So that’s the start of it…

“Over the years, lycopene, a nutrient found in tomatoes, has drawn much attraction for its ability to combat several chronic diseases including cancer,” he adds. “Moreover, lycopene being a component of major dietary source (tomato) finds acceptance with the population and its use is also not restricted as is the case with synthetic chemopreventive agents.” Indeed, lycopene is already marketed as a supplement, although specific health claims are not permitted under FDA rules for supplements without additional regulatory approval.

“With the studies planned and in progress we intend to determine the optimum levels of lycopene as a cancer chemopreventive agent, so as to tap its maximum potential,” Koul told me. “Further, we aim to investigate the detailed underlying mechanism of its cancer chemopreventive potential. Such studies would scientifically validate the anticancer abilities of phytonutrients present in vegetables including lycopene.”

You can read the full story on SpectroscopyNOW.

Tomato photo via CC on flickr.

Today, the BBC is reporting another medical “breakthrough” – high-intensity focused ultrasound (HIFU) for treating prostate cancer as an adjunct or even alternative to radiotherapy, chemo, and invasive surgery. Ultrasound can be highly focused, essentially boiling the diseased tissue rather than damaging surrounding tissues with the risk of incontinence and impotence associated with invasive surgery.

It’s good news for prostate cancer sufferers, but as far as I am aware HIFU has been used to treat prostate cancer since at least 1989. The technique was first developed in France by Inserm scientists and others and the Ablatherm HIFU was first marketed for the disease in 2000. The first “commercial” treatments were in 1993 and there have been tens of thousands since.

NHS Choices reported on HIFU back in 2009 when there was a flurry of interest from the media in this “new” technique for treating prostate cancer. It says:

“Current NICE guidance advises that the evidence supports…HIFU for prostate cancer, provided that monitoring, audit and clinical governance of any procedures are carried out. It advises that longer-term effects on survival and quality of life are unknown, and that doctors should therefore ensure that patients understand these uncertainties.”

The BBC itself has reported on HIFU for prostate cancer before, there was a report in February 2011 hailing the benefits of the “new” treatment. As an aside, they refer to the urethra as the “water pipe” in that report, how quaint. So, why is this news on the BBC Radio 4 Today program today, could it be that the editors and journalists on the show simply hadn’t heard of HIFU before and so assumed it was new when a press release came from Lancet Oncology touting the benefits over surgery (in a 41-patient trial)? You can almost bet your gland on it.

Regardless, it is all positive stuff, but it does beggar the question as to why the technique, more than two decades in the development, is only now reaching public ears…

NHS Choices recently summarised and analysed the findings of a UK study into cancer risk. It reports that for many people several factors are involved. Moreover, one’s personal risk also depends on genetics, family history and aging. According to the study in 2010, around 43% of UK cancer cases were blamed on lifestyle and environmental factors, equating to about 134,000 cancers. The research showed the following percentages for 34% of cancers in 2010 for which four key lifestyle factors were invoked:

Tobacco: 19.4%
Diet: 9.2%
Being overweight or obese: 5.5%
Alcohol: 4%

Smoking was commonly associated with lung, mouth, throat, trachea and oesophagal cancers.

Other risk factors included: occupation (3.7%), UV radiation (sun or sunbed) (3.5%), infection (3.1%), excess intake of red and processed meat (2.7%), lack of physical exercise (1%), breastfeeding for less than six months (0.5%), use of post-menopausal hormones (0.5%). Smoking was the single biggest risk factor for both men and women.

After smoking, the three biggest risk factors were: lack of fruit and vegetables (6.1%), occupation (4.9%)
and alcohol (4.6%). For women they were: overweight/obesity (6.9% link to breast cancer), infection (3.7%), UV radiation (3.6%), alcohol (3.3%), lack of fruit and vegetables (3.4%).

…nor will your Blackberry, Android handset and presumably not your iPad either.

Despite the hopes and dreams of millions of technophobes and pseudoscientists, the biggest ever study of mobile phone use shows that the devices do not increase the risk of brain tumours. The European study looked at more than a third of a million mobile phone users over an 18-year period, according to the BBC.

Researchers at the Institute of Cancer Epidemiology, Danish Cancer Society and the International Agency for Research on Cancer (IARC) in France assessed all Danes aged over 30 years born in Denmark after 1925 and subdivided into mobile phone subscribers and non-subscribers who had used the devices since before 1995. Writing in the British Medical Journal, the team describes how there were just 356 cases of the brain cancer, glioma, and 846 cancers of the CNS, which is about the same incidence rate as seen in people who did not use a mobile phone during that period. Even those who used mobiles for more than 13 years, there was no difference in risk, the researchers conclude.

So, will this be the end of the tabloid mobile phone cancer scaremongering? Of course, not! The tabloid media and the conspiracy theorists will claim the study is spurious, there will be another study (undoubtedly much smaller) that will show the opposite and that mobile phones do cause brain tumours. But, as it stands: “These results are the strongest evidence yet that using a mobile phone does not seem to increase the risk of cancers of the brain or central nervous system in adults,” Hazel Nunn, head of evidence and health information at Cancer Research UK, told the BBC.

So, is it time that the World Health Organisation abandoned its application of the precautionary principle and re-classified mobile phones as non-carcinogenic? There are always those people who are over-cautious and there always those who throw caution to the wind. But, like coffee, smoking, alcohol, crossing the road, and living in general, there are risks and precautions to be taken. It is unlikely that anyone will stop doing the things they want to do simply because there is some perceived risk associated with the activity. However, this latest study shows that mobile phone use really does not cause brain cancer. There has been no indication that anyone was seriously worried, as mobile phone use simply goes up and up. Time to stop worrying.

Frei, P., Poulsen, A., Johansen, C., Olsen, J., Steding-Jessen, M., & Schuz, J. (2011). Use of mobile phones and risk of brain tumours: update of Danish cohort study BMJ, 343 (oct19 4) DOI: 10.1136/bmj.d6387

UK cancer trends – The media has been all over the Cancer Research UK announcements on cancer rates. Specifically, the focus was on middle-aged people and the increases seen between 1979 and 2008.

NHS Choices, as ever, provides some rational words following the media frenzy and cites a few of the stats to which I’ve added percentages of diagnoses for comparison):

The highest rate of new diagnoses is among people aged 75 and over; the rate of new diagnoses in over-75s increased from 1,808 per 100,000 to 2,319 per 100,000. (That’s 1.8% in 1979; 2.3% in 2008).

In people aged 60 to 74, new diagnoses rose from 1075.9 per 100,000 to 1,370 per 100,000. (1.1% in 1979; 1.4% in 2008).

In people aged 40 to 59, new diagnoses rose from 329.1 per 100,000 in 1979 and 388.1 per 100,000 in 2008 (an 18% rise). (0.33% in 1979; 0.39% in 2008)

The lowest rate of new diagnoses is among people under 40; the rate in this age group increased from 29.5 per 100,000 in 1979 and 41.2 per 100,000 in 2008. (0.03% in 1979; 0.04% in 2008).

When looking at the rates of new diagnoses of specific cancers among people aged 40 to 59 years old, CRUK reports that: the rate of new cases of breast cancer in women has increased from 134 per 100,000 women in 1979 to 215 per 100,000 in 2008. The rates of new cases of prostate cancer among men has increased from 8 per 100,000 in 1979 to 51 per 100,000 in 2008. The rates of new cases of lung cancer in men dropped from 93 per 100,000 in 1979 to 35 per 100,000 in 2008. Moreover, despite the increases in diagnoses (actually, partly because of the increases in diagnoses), the number of people surviving cancer [for a reasonable time after diagnosis] has doubled since the 1970s. There were 2152 deaths from cancer per 1,000,000 people in GB in 1979, which fell to 1754 deaths from cancer per 1,000,000 people in 2008. I’m not sure what statistics the tabloids were focusing on with their scaremongering claims about cancer incidence, but they don’t mesh with what CRUK actually said.

NHS Choices points out that the causes of the increases were not directly investigated. However, CRUK say that one factor contributing to these increases is likely to be higher rates of detection due to the NHS breast cancer screening programme and the PSA test for prostate cancer. As opposed to chemicals, radiation, GM crops, sunspots, crop circles, or any other spurious causes. Of course, none of this should detract from the human pain and suffering of cancer, indeed it should be seen as a positive that although incidence is reportedly increasing this seems to be due to better diagnosis and life expectancy has improved because of better treatments because of the efforts of CRUK, other charities and the medical scientists they help support.

 

Related articles

• Cancer diagnoses in 40-59 age group soar 20% in a generation (guardian.co.uk)
• The cancer generation (thesun.co.uk)
• PSA Test May Help Check for Breast Cancer (webmd.com)

UPDATE: 8 July 2011 This update isn’t anything new, but something I should’ve pointed out and that is always ignored/overlookd in popular and sensationalist discussions about the health risks of electromagnetic radiation is that everything beyond the violet end of the spectrum – UV, X-rays, gamma rays – are high-energy and “ionising” forms of radiation. Everything below the red end of the spectrum – infrared, microwaves, radio waves – are much lower in energy and do not ionise molecules or atoms. They can heat things up (infra-red makes molecules vibrate, which heats them up, microwaves make polar molecules spin, the energy of which is transferred to other molecules as vibrations (heat).

The WHO’s verdict is one based on the precautionary principle. They’re scared, but they don’t know what they are scared of other than public and political pressure, they have reclassified mobile phone (cell phone) use as a “possible carcinogen”, but as far as I can see with absolutely no evidence whatsoever and with no new data or explanation as to how the emissions from a mobile phone could possible be carcinogenic. Even if they were heating up your ear, through some odd microwave effect that is not causing the kind of damage to DNA that would lead to tumour growth. A far greater risk is exposure to ionising radiation – UV etc…

Brain tumours and mobile phones – It’s interesting that the WHO has adopted what is essentially a non-scientific stance regarding the safety, or putative lack thereof, of mobile phones when it comes to effects on the human brain, and specifically the development of tumours.

The precautionary principle suggested by is unlikely to have any impact on the vast majority of users, most of whom seem either to have gone hands-free these days or use their phones mainly for smart apps and texting rather than actually having “old-school” verbal conversations with anyone. Moreover, mobile phone use has not been widespread for more than a few years, perhaps fewer than the length of time it takes for putative brain tumours triggered by those nasty electromagnetic waves to appear.

A review reported in NHS Choices and by the BBC and others, suggests there really is no link anyway. However, the review is non-systematic and lacks a lot by way of science, Choices seems to suggest.

According to Choices, the authors of the review suggest that if there is no increase in brain tumour rates in the next few years after almost universal exposure to mobile phones in Western countries, it is unlikely that there is a link between mobile phone usage and brain cancer in adults. The methodological weaknesses of underlying studies and the trend in brain tumour incidence shown here suggest that any risk of brain tumours resulting from mobile phone use is likely to be very small, and possibly even non-existent.

We are constantly bathed in electromagnetic radiation from countless sources, it is very unlikely that we will ever be able to unravel the source of any carcinogenicity in the future either, especially given the advent of countless other wireless technologies.