This post is on Healthwise
February 8, 2015
BY PROF DR TEO SOO HWANG
The vast majority of research does not show that cancer is the result of bad luck. Rather, it shows that two-thirds of cancer are theoretically preventable. Photo: AFP
Is bad luck the reason some people have cancer while others are spared?
Why me? No matter young or old, a smoker or a non-smoker, healthy or fat, fit or sedentary, if cancer happens to us, we ask, “Why me”?
Many cancer patients in Malaysia ascribe it to bad luck, bad karma, God’s will. On Jan 2, a research paper published in one of the world’s more reputable scientific journals,Science, appears to support this view that most cancer types are just bad luck.
The research study used mathematical modelling to study why some cancers (like colorectal cancer) are more common than others (like sarcomas), and proclaimed that two-thirds of individual cancers arise from random events, such as how cells divide and grow.
This eye-catching message caught the media’s attention and the take-home message was that most cancers are due to bad luck, and not to inherited genetics or lifestyle and environment factors.
The vast majority of research does not show that cancer is the result of bad luck. Rather, it shows that two-thirds of cancer are theoretically preventable.
We know that lung cancer became over 10 times more common as tobacco use increased, and its incidence is now decreasing in many European countries because of strict anti-smoking regulations.
Although not all smokers get lung cancer (they are more likely to die of heart disease before dying of cancer), they are more than 10 times more likely to get lung cancer than a non-smoker.
What we know with some certainty, is that nearly all lung cancers would be prevented if nobody smoked.
Similarly, we know that oral cancer is 10 times more common in India and South-East Asia because of chewing betel quid, mixed in with areca nut and tobacco.
Although not all sirih-chewers get oral cancer, they are more than 10 times more likely to get it. Nearly all oral cancers would be prevented if nobody had this habit.
We know that nearly all cervical cancer would be prevented if all girls received the human papillomavirus (HPV) vaccine.
We know that two-thirds of liver cancer would be prevented if everyone received the hepatitis B virus vaccine.
Just like not all smokers develop lung cancer, not all women infected with HPV and not all individuals infected with the hepatitis B virus develop cervical or liver cancer, respectively.
The research study does have important implications. For some rare cancers, the mathematical model suggests that it is mostly random errors that occur when cells divide, and the scientists suggest that more research funding should go towards finding methods for early detection, rather than prevention.
For some cancers, the mathematical model suggests that random errors only account for a small proportion of the risk (suggesting that genes, lifestyle and the environment are important) and efforts to prevent these cancers must play a central role in our war against cancer.
In 2012, the World Health Organisation (WHO) estimated that there were 14.1 million new cancer cases and 8.2 million cancer deaths.
This year, WHO estimates that there will be 15 million new cancer cases and 8.7 million cancer deaths.
Our estimates are that 40,000 Malaysians will be diagnosed with cancer and there will be 20,000 deaths due to cancer.
The leading cancers are breast, lung, colon, nasopharyngeal and cervical cancer.
The vast majority of deaths due to each of these cancers are preventable. The real question is whether we are going to take cancer prevention seriously.
The first step is by making sure that we have accurate information.
Prof Dr Teo Soo Hwang is the chief executive of Cancer Research Initiatives Foundation (CARIF). CARIF is an independent Malaysian non-profit cancer research organisation working towards a future free of the fear of cancer through impactful research and outreach programmes. For more information, visit www.carif.com.my or email info@carif.com.my.
http://www.thestar.com.my/Lifestyle/Health/2015/02/08/Hows-your-cancer-luck/Go to Healthwise for more articles
