Monday, 26 January 2015

5. Self Help in Cancer diagnosis and prevention


Becky Adlington discusses Health, Nutrition and Wellbeing 
at the Telegraph Be Fit Show, 1-3 May.

     In his UCL report Overcoming Cancer in the 21st Century, Professor David Taylor has forecast that deaths from cancer will be eliminated for all age groups except the over-80s by 2050.  
     This is an exciting prospect that the press trumpeted when the report was published on 14 January.  
     However, while extolling the significant advances in cancer treatment and survival rates over the past decades, Professor Taylor's forecast was tempered by the crucial provisos that recent gains in prevention and treatment must carry on apace.
     Responsibility for such future gains rests not only with a National Health Service, originally designed  by the government in 1948 for a population of 50 million and now in danger of collapse under the weight of 63.5 million in 2015, but also with us individually.
     The prospects for cancer care in the NHS and cancer care are indeed gloomy, with hospitals running out of cash and reducing clinical staff. 
     NHS waiting times for cancer treatment worsened in 2014 and will worsen  in the future unless both Labour and Conservative funding pledges are revised considerably upwards after the General Election in May, according to Professor John Appleby, Chief Economist at the King’s Fund.
     We can help ourselves in cancer diagnosis and treatment, however, by being better informed about symptoms, (pick up leaflets from your local pharmacist or check online), being less afraid of cancer, and more willing to get ourselves tested. 
     We can also do much to prevent the onset of a number of cancers by adopting a healthier lifestyle and diet.  "The links between cancer and smoking, heavy drinking, obesity, poor diet and lack of exercise are now clinically well established",  states Dr. Ian Hampson, of the Institute of Cancer Sciences. 
     We ignore those links at our peril.

Further Reading:
Overcoming Cancer in the 21st Century  UCL Report.
The King’s Fund  Ideas that change health care.
Institute of Cancer Studies  Improving cancer outcomes through research and education.

Monday, 19 January 2015

4. Is Bad Luck to blame for most Cancers?


It is perhaps presumptuous for me cross swords with the distinguished Professor Bert Vogelstein of the John Hopkins University School of Medicine. He it was, you may remember, who was recently quoted as stating that "All cancers are caused by a combination of bad luck, the environment and heredity".
     His comment was supposedly to clarify the published results of his team's research finding that random mutations, which occur in DNA when cells divide, are responsible for two-thirds of adult cancers, while the remaining third are linked to environmental factors or defective inherited genes.
     There are surely provisos to Professor Vogelstain's statement however which were either left unsaid, or were omitted by the press, which prefers to paint word images in stark black and white for headline value and ignore the important shades of grey in the small print.
     It is that dangerous use of the word "ALL" in the published statement that worries me - and many others. For example 30 years ago cervical cancer might have been lumped with the group of cancers caused by "bad luck" whereas it is now well established that infection with the human papilloma virus causes this disease.  Indeed there are other examples, such as the hepatitis viruses HBV and HCV, which are the main cause of liver cancer and there is also a virus known to cause leukaemia in adults. Clearly this begs the question: “Are there viruses, as yet unknown, which can cause cancer if left undiagnosed and untreated?" This is not an easy question to answer since many of these types of viral infection produce few symptoms in the majority of people, which makes them hard to detect. Furthermore, the virus can be cleared during the time period between acquiring the infection and developing the cancer which can take as long as 50 years. The virus may be gone but the damage it caused persists and contributes to development of the malignancy, leading to cancer – what is known as the “Hit-and–Run” hypothesis. 
     At present approximately 20% of all human cancers are known to be caused by infections but we do not yet know whether this is an underestimate.  I bet that there will be future occasions where research will show that the answer is "Yes"!
     Similarly, while we now know that there is a strong correlation between aspects of poor lifestyle, (smoking/alcoholism/obesity/food choice/sedentary habits, or a lethal combination thereof), and some cancers, little research has been done on the positive effects of nutrition and diet on the prevention of some of those cancers now dismissively binned as 'bad luck'.
     Meanwhile, until cancer prevention rather than cure becomes the norm, we must stress the need to focus more resources on finding ways to detect such cancers at an early, curable stage, while charities such as Caring Cancer Trust, The Humane Research Trust and the Cancer Prevention Research Trust fund researchers like Drs Ian and Lynne Hampson in their continuing work to find those elusive infectious causes of cancer and, hopefully, non-invasive cures. 

Drs Lynne and Ian Hampson, PhD. Photo Caring Cancer Trust

 Dr Ian Hampson PhD, Reader in Viral Oncology, University of Manchester, writes in response: 

      The thing about Professor Vogelstein is that what he says is true but it is not the whole story since, as you rightly point out, viruses and other environmental factors, (some obviously dietary), combine with the genetic hand we have been dealt to promote the development of cancer. If you can prevent or limit exposure to the former it has got to improve our chances. For example worldwide cervical cancer kills 275,000 women every year and we know that, if you cure the virus, women hardly ever get the disease.
      The problem with nutrition and diet is that we keep getting it wrong. It seems that the diet that people are exposed to in early life, and even in utero, fixes the goalposts for what our bodies regard as normal. If we step outside this by a good measure problems can ensue.

Further Reading
utube : Dr Ian Hampson PhD discusses recent cancer research breakthroughs.

3. Obesity, Overweight and Cancer

      Being overweight or obese may increase your risk of contracting one of the 10 
of the most common cancers. While it is well known that overweight can increase 
the risk of diabetes, heart disease, high blood pressure and stroke, recent research 
by Dr. Krishnan Bhaskaran, of the London School of Hygiene & Tropical Medicine 
in the UK and published in the medical journal The Lancet, also suggests that 
overweight and obesity substantially increases the risk of Cancer. 
The risk is particularly strong in the case of the following common cancers: 
Womb (62% increased risk); Gallbladder (31% increased risk); Kidney 
(25% increased risk); Cervical (10% increased risk); Thyroid (9% increased risk); 
Leukaemia (9% increased risk). 
        The researchers also found that overweight and obesity was associated with a 
19% higher risk of liver cancer, a 10% higher risk of colon cancer, a 9% higher 
risk of ovarian cancer and a 5% increased risk of breast cancer, together with 
some risk of prostate cancer.
       Dr Bhaskaran's research team noted that all increased risks varied both with 
different cancers and with an individual’s overweight, sex and menopausal status; 
the overweight affecting cancer risk through a number of different processes, 
depending on the cancer type.

Oprah Winfrey lost pounds through diet and exercise
     From their findings, the team calculated that overweight or obesity possibly                                    accounts for 41% of womb cancers in the UK and more than 10% of all gallbladder,                                  kidney, liver and colon cancers. They also calculate that on current UK weight                                      increase trends, an added 8 – 10 pounds in adult weight across the UK population                                         could eventually cause an additional 3790 cases of the 10 most common cancers 
every year; a daunting statistic that provides food for thought about our individual 
dietary regime.                                                                                                                                                                                                    
     Other studies, relating to Diet and Cancer, highlight  processed red meat, salt,                                        sugar and artificial sweeteners as potential cancer risks.  Your overall diet can affect 
your Cancer risk.   About one-third of all Cancers can be prevented by eating well, 
being active and  maintaining a healthy body weight.                                                                                                                       
     Eating well is all about balance. Specific types of food can reduce or increase the                                        risk of cancer. For example, eating plenty of fibre, fruit and vegetables can help  
maintain healthy body weight, which reduces the risk of Cancer. But studies show  
that eating processed meat increases the risk of Colorectal Cancer.  
     The foods we choose to eat can help us reach and maintain a healthy weight,                                           which reduces cancer risk. 

Further reading:  

The Lancet  Full Research findings. 
Lancet Comment : Obesity: a certain and avoidable cause of cancer
Canadian Cancer Society : Sugar and Cancer 

Thursday, 15 January 2015

2. Diet and Prostate Cancer

The synopsis below is from the report on Prostate Cancer and Nutrition, by  Stanley A Brosman, MD  Clinical Professor, Department of Urology, University of California in Medscape, (updated October 2014).

     Prostate cancer has become such a frequently diagnosed condition that much research has been undertaken to understand its etiologic factors and how its onset can be prevented or delayed. Although the primary risk factor for developing prostate cancer is aging, the role of diet and nutrition in the development and progression of this and other cancers has received increasing attention.
     In 2002, the American Institute for Cancer Research published a study concluding that 200,000 of the 600,000 cancer deaths in the United States each year could be prevented through a combination of dietary changes, adequate physical activity, and maintenance of appropriate body weight. The report also noted that avoidance of tobacco and alcohol could prevent an additional one third of cancers. The study was carried out by a panel of 16 experts, who reviewed 4500 studies related to diet and cancer.
     In 1982, The National Academy of Science presented convincing evidence concerning the relationship between dietary fat and cancer. Dietary factors identified as having an etiologic role in prostate cancer include excessive fat intake, obesity, excessive intake of estrogens and phytoestrogens, and the consumption of burned or charred foods.
     The principal message from nutritional studies and cancer in humans has been an endorsement of the benefits of a diet consisting mainly vegetables, fruits, grains, and fish, combined with restricted caloric intake and exercise. Such a diet provides multiple micronutrients packaged in their most effective form. For example, whole-grain bread provides fiber, iron, vitamin E, and folate. Fruit juices such as pomegranate juice provide antioxidants.
A set of dietary principles derived from areas in which evidence of a dietary influence on cancer risk in general is substantial, even if not conclusive, have been agreed:  
1.  Limit or avoid dairy products.  
         2.  Avoid grilled, fried or broiled meat.  
               3.  Emphasise fruit and vegetables in diet.

     Dietary modifications, coupled with exercise and lifestyle modifications, may affect cancer growth rates. These measures can be used in concert with currently accepted therapy. Relying on diet alone to treat prostate or any other cancer is unrealistic.  

Dr Brosman's report is necessarily cautious and reflects current medical thinking. The apparent benefits of a diet consisting mainly of vegetables, fruits, grains and fish combined with restricted caloric intake and exercise is acknowledged and endorsed. However cancer prevention, treatment or cure through a dietary regime is not accepted, presumably because the such dietary effects have yet to be verified by controlled medical research. The report emphasizes the difficulty of such research, "given the inherent heterogeneity of any study population, the variations in individual lifestyles, and the quantitative and qualitative complexity in food and food products"  To this can be added the very long time factor and cost such research would entail, which means that such a research project is not going to happen. 

1. Red Meat and Cancer

     People have been banging on for some time now about the cancer risks of eating too much red meat or processed meat.  
     A recent Harvard University study published this year has shown that high quantities of red meat appear to raise the risk of breast cancer in women by 22%, while an earlier study showed that the risk of bowel cancer was raised by 33%. 
     The problem has been that nobody knew why large amounts of red meat had this effect on humans but not on other mammal carnivores. 
     New research on 'red meat derived glycans' at the San Diego Glycobiology Research and Training Center of the University of California, presented for publication in Proceedings of the National Academy of Sciences, appears to provide the reason for this health anomaly.  
     Red meats are evidently particularly rich in a sugar which is naturally produced by other mammal carnivores but not by humans. When humans eat large amounts of beef, pork or lamb therefore, their bodies trigger an immune response to the foreign sugar, producing antibodies which promote inflammation and possible progression not only to Cancer but also to Type 2 Diabetes, or cardiovascular disease which in turn lead to stroke and heart attack. 
     Red meat is accepted as a good source of protein, vitamin and minerals, but an increasing body of research suggests it is bad for long-term health if taken in large amounts.  So what do health experts consider "a large amount"?  Dieticians now recommend eating no more than 2.5oz (70g) a day. This is the equivalent of three slices of ham, one lamb chop or two slices of roast beef a day. And if you are a carnivore, at least one meatless day in the week would certainly be good for you.
Further Reading.
Proceedings of the National Academy of Sciences USA.  Study on the  connection between red meat, inflammation and cancer progression. 
Nature Communications . Fat, Fibre and Cancer Risk.