Cancer is the second leading cause of death after CVD in the Asia-Pacific region. Cancer was the cause of an estimated 4.5 million deaths (or 16.3% of total deaths) in Asia-Pacific in 2016 (https://www.who.int/data/gho).
There are more than 100 different types of cancers, with most named after the organ in which they start. Cancer occurs when abnormal cells divide without control and are able to invade other tissues. While genetics are a risk factor, only about 5% to 10% of all cancers are inherited. Modifiable risk factors such as smoking, obesity, exercise, and excess sun exposure, as well as environmental exposures, explain as much as 90‑95% of all cancer cases (Islami et al., 2017[16]; Wilson et al., 2018[17]; Whiteman and Wilson, 2016[18]). Prevention, early detection and treatment remain at the forefront in the battle to reduce the burden of cancer, and progress towards fighting cancer needs to be monitored not only by mortality rates but also by survival estimates, taking account of early detection of the disease and the effectiveness of treatment (OECD, 2013[19]).
Mongolia had higher cancer mortality rates, all with over 200 deaths per 100 000 population in 2016 (Figure 3.16). Cancer deaths were less common in Sri Lanka, India, Nepal, Bangladesh and Fiji, and they had less than 90 deaths per 100 000 population.
The average rate of death in Asia-Pacific countries and territories was lower than that of OECD countries (115.5 in lower-middle and low, 111.9 in high and 104.1 in upper-middle income Asia-Pacific countries and territories versus 120.9 deaths per 100 000 population in 2016). While cancer mortality had increased in all Asia-Pacific countries and territories and territories, India, Papua New Guinea, Brunei Darussalam and Fiji reported an increase from 2000‑16 of 1.2%, 6%, 12.5% and 27.2% respectively.
Trachea, bronchus and lung cancer were the leading type of cancer in upper-middle and high-income Asia-Pacific countries and territories (Figure 3.17), accounting for 19.7%, and 19.8% of all cancer deaths – on average – respectively in 2016. Liver cancer was the first cause of cancer deaths in lower-middle and low income Asia-Pacific countries and territories, accounting for around 17% of cancer deaths in 2016. In Mongolia, with the highest cancer mortality, the large proportion of deaths was due to liver cancer, precipitated by hepatitis B infection. Besides Mongolia, liver cancer deaths occurred frequently in the Lao PDR, Viet Nam and Thailand. Incidence is expected to fall in coming decades, with increased immunisation for hepatitis B (see indicator “Childhood vaccination” in Chapter 7).
Other main causes of cancer deaths were stomach, colorectal and breast cancer. Mortality from stomach cancer accounted for 6.3% and 5.7% all cancer deaths in high-income and upper-middle income countries and territories respectively, linked to Helicobactor pylori infection, with deaths more prevalent in Mongolia, China, the Republic of Korea, Japan and Viet Nam. Colorectal cancer deaths were higher in New Zealand, Singapore and Brunei Darussalam. Breast cancer deaths, the most common cause among women, were responsible for over 15% of all cancer deaths in Pakistan and Fiji, and the mortality rate was also high in Solomon Islands, Malaysia and the Philippines.
Cancer causes the highest economic loss among top causes of death worldwide as a large proportion of cancer deaths occur in the economically productive age group (Figure 3.18). OECD and high-income Asia-Pacific countries and territories had high mortality rates among older people (70 years or more), whereas lower-middle and low income Asia-Pacific countries and territories had high mortality rates for people aged less than 60 years. For a large number of cancers, the risk of developing the disease rises with age but in lower-middle and low-income countries and territories, life expectancy is considerably lower than other countries and territories, so the older people die of other diseases.
As with cardiovascular disease, the ageing of the population will lead to many more cases of cancer in coming decades, taxing underprepared health systems. Since the drugs and technologies for treating patients are expensive, cancer control planning in the Asia-Pacific region might more effectively target smoking, physical activity and overweight/obesity. Early diagnosis is also a key to reducing mortality, so access to cancer diagnosis and care needs to be promoted through public health interventions or wider health coverage (OECD, 2013[19]).
