Cancer Incidence: Now and the Next 20 Years
The ongoing COVID-19 pandemic does not stop other diseases from progressing. Cancer is still regarded as the second leading cause of mortality worldwide despite the high number of SARS-CoV-2 infections late 2019.
Cancer is the abnormal growth of cells that can occur in any part of the body. Each of our cells regulates its growth following a specific pathway. But when a certain gene mutation alters the pathway, the cells can overgrow, expanding to areas beyond their usual boundaries. Some can grow for a little bit and stop, but some keep expanding their roots taking place in other sites of the body.
During the last year of the pandemic, GLOBOCAN recorded 19.2 million new cases of all cancer types with 9.9 million deaths occurring in 2020 alone. Even with the impact of the pandemic on the healthcare system, the number of cancer deaths is three times higher compared to the cumulative death of COVID-19 cases up to April 20 this year.
The study found 50% of the new cases and 58.3% of cancer deaths take place in Asia for all cancer types. Europe then placed second and followed by America in third place. The high number of cancer incidences in Asia can be attributed to the large number of the world’s population residing in the continent.
The top five of the highest incidence of cancer types:
Female breast cancer (11.7% of total cases),
Lung cancer (11.4%),
Colorectal cancer (10%),
Prostate cancer (7.3%),
Stomach cancer (5.6%)
The main cause of cancer death in 2020 is lung cancer with 18% deaths of total cancer mortality worldwide, while female breast cancer is in fifth place with 6.9% of death cases. This shows that female breast cancer screening and preventive measures are improving globally and have resulted in a decreased number of deaths thanks to the early diagnosis and management of the cases.
Worldwide, men have a higher rate of cancer incidence compared to women, with 222 cases in men per 100,000 men and 186 cases in women per 100,000 women. Lung cancer is the most frequently occurring cancer in men, followed by prostate and colorectal cancer. While in women, breast cancer has the highest incidence, followed by colorectal and lung cancer.
Notably, the highest death rate in men per 100,000 persons is found to be in Eastern Europe, followed by Central America. Among women, the highest death rates are in Melanesia followed by Central America and South-Central Asia.
Fast forward to 2040, the same study estimated a total of 28.4 million new cancer cases, showing a 47% increase from 2020. The rise of cases is projected to be relatively higher in countries with low and medium human development index (HDI), with a 95% and 64% increase respectively. But the absolute burden is highest in countries with high HDI with 4.1 million new cases in 2040 compared to 2020. It’s partly because they are having a marked increase of cancer risk factors like smoking, unhealthy diet, excess body weight, and sedentary lifestyle (which is a lifestyle where the person spends most of the time sitting down with less physical activities).
Many emerging cancer like cervical, liver, and stomach cancer are related to infection and poverty. The incidence is especially higher in low-income countries. Additionally, the burden of cancers is also associated with social and economic transition, which can overwhelm the healthcare system in many low-income countries. These points should be considered in developing cancer control strategy priorities in the future.
There is a diverse pool of cancer types that continue to increase in both the number of cases and deaths. It is a sign of a need for more intense effort to control the disease on a global scale. The preventive and curative intervention of cancer should be put into the health strategy of each country to reduce the future burden of cancer.
In 2040, there will be a 47% increase in cancer cases worldwide.
The most common type of cancer is female breast cancer, but lung cancer has the highest death rate.
Many of the emerging types of cancer are related to infection, poverty, and social and economic transition.