Understanding methods of cancer detection

The problem with the investigations we have for breast and prostate cancers is they aren’t good at early detection of cancer. The PSA blood test for prostate cancer doesn’t really pinpoint early cancer development and, by the time mammograms suggest cancer might be present in breast cells, cancerous changes have already firmly established themselves.

Why these tests survive is partly because, except for those reading this article, most of us don’t really care. Cancer is always something that is going to happen to someone else, which is why food courts everywhere regularly feed an ever-receptive clientele cancer-stimulating foods.

A good friend of mine is a case in point. His brother developed prostate cancer at the age of 59. His sister has a melanoma and his father succumbed to bowel cancer. The genetic dice would appear to be pretty firmly stacked against him. His health habits and diet are far from cancer-neutralising. I thought that giving him my book, which has segments on cancer prevention, would initiate some behaviour changes. That was a year ago and he still hasn’t opened the book.

As the iPhone cements us firmly in the age of narcissistic self-obsession I’m hoping that one of the side-effects of this daily dance might be an embracing of personalised medicine. Genetic testing is going to provide precise signatures that will outline unique propensities to develop cancer, allowing us to take pre-emptive action long before cancer cells have overwhelmed our defences. Instead of avoiding sugar for the rest of our lives and taking a swag of vitamins, our genes will tell us exactly which healthy foods we need to consume and the specific supplements we need to supercharge our immune systems.

We are about to move into an era that will witness the emergence of testing that will identify cancer cells in the early stages of development, before they have set up shop in our bodies, thereby rendering tests like the PSA and the mammogram obsolete. The CSIRO in Adelaide has already developed what sounds like a test truly befitting of the space age called the cytokinesis-block micronucleus cytome assay, which zeroes in on DNA damage.  At the same time they are focusing on the diet as well as the vitamin and mineral supplements needed to reverse this damage so that cancer cells can be nuked before they emerge from their foxholes.

This would mean that we could have the test that tells us if we have DNA damage along with an individualised health program to overturn this damage. Although this has yet to be trialled, I’m hoping the gene testing and the DNA research carried out by the CSIRO will provide complementary information that is not conflicting.

Aside from the DNA, which essentially tells our cells how to behave, RNA, up to now thought to be DNA’s messenger boy, has a will of its own in determining the fate of our cells. Trailblazing research presented at the Human Genome Meeting held in Sydney in March 2012, which assembled leaders in the field of genetics from around the world, revealed that, when it comes to the detection of breast, prostate and colon cancer, focusing on the workings of RNA might provide the basis for establishing a vital early warning system.

Breast cancer

Micro-RNAs are components of RNA associated with genes that either promote cancer or protective genes that are turned off, which allows cancer cells to multiply. Research has isolated specific micro-RNA proteins that are connected with the genesis of breast cancer cells and identifying these will provide information that is far more useful than mammograms or MRI scanning for targeting an advanced strike.

The PSA has become another useful indicator of breast cancer cell formation. Traditionally thought to reside exclusively in the domain of the prostate, this substance is actually manufactured by many organs but at levels that are so low they escape the detection of conventional testing methods. In 2011, researchers in Taipei developed ultrasensitive technology that made it possible for the PSA test to tag breast cancer cells, serving up another means for the advanced recognition of these cells. All we now need to do is convince a reactionary medical establishment to adopt these innovative and potentially life-saving technologies.

With regard to developing breast cancer, alcohol, obesity, foods with a high glycaemic index and meat cooked at high temperatures are the primary offenders. Studies show that taking extra zinc and betacarotene as well as vitamins C and E may protect against the development of breast cancer.

Prostate cancer

RNA testing is also establishing itself as a useful means of recognising the early germination of prostate cancer cells. Prostate cancer antigen testing (PCA3) signals the presence of certain types of RNA called long non-coding RNA which, like the breast cancer micro-RNAs, is associated with genes that either turn off or set the cancer-promoting process in motion.

While enthusiasm for using this form of testing has yet to be ignited there are at least some experts who assert that the PCA3 test might have advantages over the traditional PSA measurement for the early diagnosis of prostate cancer, which would minimise unnecessary biopsies of the prostate, currently driven by the results of PSA testing.

Obesity, eating more than five servings a week of processed or grilled meat, dairy, even skim and low-fat milk and polyunsaturated fats found in sunflower, safflower, flaxseed and canola oils are associated with increased prostate cancer risk.

Eating more than two serves of cooked tomatoes a week, drinking more than five cups of green tea daily, and a good intake of soy and cruciferous vegetables are protective.

Taking this preventive strategy to the next level will involve seeing how these nutrients interface with genes and DNA repair mechanisms to individualise the war against cancer.

Dr Michael Elstein is a Sydney-based anti-ageing physician and writer. He is the author of two books, Eternal Health: The Comprehensive Guide to Anti-Ageing for the New Millennium and You Have the Power: Why didn’t my doctor tell me about this?