THERE ARE few people in Ireland who haven’t experienced someone close to them dying from cancer. One in three people will develop the disease at some stage in their lives.
Yet, the great untold story about cancer in the past decade or so is the number of people who are diagnosed with it and live to tell the tale.
This is the theme of molecular biologist Lauren Pecorino's new book, Why Millions Survive Cancer – the Success of Science.
What’s interesting about this book is Pecorino’s skill in writing about the science of cancer in everyday language. She explains clearly how scientific knowledge about and better management of the disease has grown rapidly in the past few decades.
Crucially, she also points out how more and more evidence shows that the lifestyle choices we make (for example, smoking, alcohol and weight) can reduce our risk of cancer hugely.
A lecturer in cancer biology and therapeutics at the University of Greenwich in London, Pecorino explains how cancer results from the abnormalities in cells which then multiply.
This uncontrolled cell growth at the original tumour site is made all the more lethal by the spread of cancer to distant areas of the body.
This process called metastasis, which Pecorino explains in detail, is the cause of 90 per cent of cancer deaths. Knowing this makes early diagnosis (before metastasis occurs) – and therefore screening – all the more critical.
Pecorino also blows out of the water many myths that have developed about cancer. The first of these is something that is widely believed – which is that many cancers are hereditary.
Instead, according to Pecorino, cancer is only very rarely inherited. “About 5-10 per cent of breast cancers are due to a hereditary syndrome,” she writes.
It is perhaps the knowledge of these specific cancers and the screening of family members which has given us the mistaken belief that many cancers are passed from one generation to the next.
“The take-home message is that most carcinogens [cancer-causing agents such as tobacco smoke, certain chemicals and infectious agents] are mutagens [an agent which makes a permanent change in our genetic code] that target genes in somatic [body] cells of an individual over their lifetime,” she writes.
She says that we must remain alert to potential carcinogenic effects of what is hailed as progress in our society. Here, she is referring to pesticides, fertilisers, food additives and some medical treatments such as hormone replacement therapy.
Exposure to natural and human-made chemicals (including alcohol, tobacco, chemicals released from cooking at high temperatures) in our environment accounts for two-thirds of cancer, according to Pecorino.
Cigarette smoking is associated with cancer of the mouth, larynx, oesophagus, stomach, liver, pancreas, kidney, bladder and ureter too – essentially all organs that are exposed to the carcinogens as they enter and leave the body. The good news is that most lung cancer can be avoided by not smoking.
In her book, Pecorino also explains how the standard treatments for cancer – surgery, radiotherapy and chemotherapy – have become more sophisticated, for example, the way robotics and imaging have led to more precise and less invasive surgery and radiotherapy.
She also celebrates the arrival of new cancer therapies which directly target specific gene products (proteins) which are known to cause particular types of cancer. And she charts the research journey of Glivec, the leukaemia medication which, due to its huge effectiveness, became the fastest approved cancer drug in history.
In a chapter on future directions, she talks about how nanomedicine – the use of tiny agents as a drug-delivery system to targeted cells – is an area that promises to deliver better cancer treatments soon.
She also writes about how researchers are discovering more biomarkers for specific cancers which, with more advanced screening techniques, will herald the much talked about era of personalised medicine.
Pecorino celebrates the fact that people now talk more openly about cancer. The development of about 20 cancer survivor parks across the US and Canada is testament to the achievement status surviving the disease has reached.
And while she is a huge promoter of screening for specific cancers (colorectal and breast), she says the fact that we can make lifestyle changes to decrease our cancer risk “needs to be screamed from the highest mountain”.
Indeed, the Food, Nutrition, Physical Activity and the Prevention of Cancerreport by the World Cancer Research Fund states that the maintenance of a healthy weight throughout life may be one of the most important ways to protect against cancer.
Why Millions Survive Cancer – the Success of Science(Oxford University Press)
Survival Strategy: Cut out cancer risk
- Be as lean as possible without becoming underweight.
- Be physically active for at least 30 minutes every day.
- Avoid sugary drinks. Limit your consumption of processed foods high in added sugar or fat and low in fibre.
- Eat more of a variety of vegetables, fruits, wholegrains and pulses.
- If you drink alcohol, limit your consumption to one drink a day for women and two drinks a day for men.
- Limit your consumption of salty foods and foods processed with salt.
- Don’t rely on food supplements to protect against cancer.
- Have your babies young if you can. Pregnancy and breastfeeding are lifelong protective factors against breast cancer.
- Don’t chew or smoke tobacco.
Adapted from The Food, Nutrition, Physical Activity and the Prevention of Cancer report(wcrf.org and aicr.org)
