As part of our regular series on the risks of getting common chronic diseases, we look at the risk of getting cancer.
Cancer is such a common illness now that it has been estimated that more than 1 in 3 people (33 per cent) will develop cancer at some point in their lifetime, according to MacMillan Cancer Support. Cancers can occur at any age, but the risk of developing cancer increases with age. The probability that a man will develop cancer in the next 12 months doubles from 65-69, when it is 1.8 per cent to 3.5 per cent when he is over 85 years old.
The same jump is seen in older women, rising from a 1.3 per cent chance for women aged between 65-69 to 2.1 per cent when she is over the age of 85, according to figures from Cancer Research UK.
By 2030 it is estimated that three million people in England will have had some form of the disease, which is caused by abnormal cell growth. Around one third of cancers, including lung cancer and bowel cancer are linked to smoking, diet, alcohol and obesity, but age is a major risk factor. Figures show that death rates from cancer accelerate as people age. ‘Tom Stansfeld, health information officer at Cancer Research UK explains: ‘Cancer is a disease that develops when cells’ DNA gets damaged, upsetting the normal process of cell growth, division and death and letting cells grow out of control. DNA damage can builds up over time so as people get older, their risk goes up.’ Programmed cell death, which is the natural process which means that cells are constantly renewed, is called apoptosis, and when this process breaks down, cancer begins to form. Instead of dying like a normal healthy cells, cancer cells start multiplying freely and spread throughout the body. This is a cumulative effect so cancer becomes more likely with age. In fact, 63 per cent of cases are diagnosed in people aged 65 and over, according to The King’s Fund.1.
The average number of cancer cases diagnosed in a given year rises rapidly in both men and women from the age of 60 to over 80, according to 2009-2011 figures published by Cancer Research UK. The lifetime risk of developing cancer is about one in three people. The probability of a man aged 65 to 69 being diagnosed with cancer in the next year is 1.8 per cent. But by the time a man is aged between 80 to 84, that probability has gone up to 3.2 per cent and the probability of a man aged 85+ being diagnosed with cancer in the next year is 3.5 per cent.
Women of all ages have less risk of being diagnosed with cancer than men. The probability of a woman aged 65 to 69 being diagnosed with cancer in the next year is 1.3 per cent, going up to 2.1 per cent for women over the age of 85. This is probably due to the prevalence of prostate cancer in men – it affects most men over the age of 80.
Lung cancer is the leading cause of death from cancer in the UK, although it is not the most common cancer. Breast cancer is the most common cancer in women, followed by bowel cancer and then lung cancer. Prostate cancer is the most common cancer in men, followed by lung cancer.
Professor Ian Smith, head of the Breast Unit at the Royal Marsden Hospital, says that although the lifetime risk of breast cancer for a woman is 12.5 per cent, this rises steadily with age. Just over 80 per cent of breast cancers occur in women who are over the age of 50. Around a third (34 per cent) of cancer cases diagnosed in females aged 50-74 are breast cancers, many of which are diagnosed through mammogram screening. Nearly half of all breast cancer cases are diagnosed in people in the 50-69 age group, but risk does increase with age. Survival rates are improving all the time. According to Cancer Research UK, 85.1 per cent of adult female breast cancer patients in England and Wales survived their cancer for five years or more in 2005-2009 compared with 86.6 per cent in 2010-2011. ‘The improved survival rates are due to earlier diagnosis and improved treatments,’ says Professor Ian Smith.
Prostate cancer, which accounts for more than a quarter (28 per cent) of cancer cases diagnosed in men aged between 50-74, is so common in elderly men that if it was reported accurately, it would probably be found in most men over the age of 80, according to Chris Parker, a consultant prostate oncologist at the Royal Marsden. ‘However, only 3 per cent of all men die from prostate cancer, because it is too slow growing to cause health problems and death occurs because of something else.’ Prostate cancer is the most common cancer in men, followed by lung cancer.