Last fall, the International Agency for Research on Cancer (IARC) released data from 185 countries for 36 cancer types that show the ever-growing burden of the disease despite progress.
Occurrence rates for some cancer types have decreased in certain regions, but overall, most countries are facing increasing numbers of new cancer diagnoses that require treatment.
This stems from several factors. The world’s population is on the increase, and people are living longer. It is estimated that close to 9 percent of the world’s population is age 65 or older. Aging is the biggest risk factor for cancer.
Also, though it is estimated that 40 percent of cancers are considered preventable especially as populations transition out of poverty, social and economic development present other cancer risks associated with lifestyle.
Education is key in helping to avoid these risks.
The IARC report notes that overall rates of cancer for many types are higher in countries considered to score well on what is known as the Human Development Index, which measures factors like education, standard of living and quality of life in terms of health and longevity.
IARC estimates the number of cancer survivors in 2018 to be 43.8 million.
Its 2018 estimate for new cancer cases is 18.1 million and 9.6 million for cancer deaths.
Nearly half of these new cases and more than half the deaths are said to occur in Asia, partly because that is where nearly 60 percent of the world’s population lives.
Europe, which has about 9 percent of the world’s population, is said to have about 24 percent of the new cancer cases in 2018 and 20 percent of cancer deaths.
North and South America, which have about 13 percent of the world’s population, are said to account for 21 percent of the new cancers in 2018 and about 14 percent of the deaths from cancer.
A higher percentage of death rates compared to incidence rates in both Asia and Africa are attributed in part to limited access to treatment, as well as later diagnosis and cancer types with poorer survival outcomes.
The most commonly diagnosed new cancers in 2018 are lung and female breast followed by colorectal, prostate and stomach, according to IARC.
Lung cancer accounts for the largest number of cancer deaths worldwide in 2018 followed by colorectal, stomach, liver and female breast cancers.
The fact that lung cancer is cited as a leading cause of death in both men and women across the globe and as the leading cause of death for women in 28 countries says a great deal about today’s world.
The highest rates for lung cancer in women are said to occur in North America, Northern and Western Europe, China, Australia and New Zealand.
Smoking does top the list as reasons given for these rates in various reports, but other carcinogen exposures cited include air pollution, toxins in the work environment, as well as lack of access in some countries to quality medical care.
Smoking tops the list as the most important preventable cause of cancer deaths worldwide. According to the World Health Organization, 22 percent of all cancer deaths are directly related to tobacco use. Over 2 million people worldwide die of lung cancer yearly and up to 90 percent of lung cancer is tobacco-related. Other carcinogen exposures such as air pollution and industrial exposures also are important causes of cancer. Poverty and lack of access to advanced medical care also contribute to cancer deaths worldwide.
The Geneva-based IARC’s ongoing research continues to show what those of us in medical fields related to cancer have long advised that healthy choices around tobacco, excessive alcohol use, diet, nutrition and amounts of physical exercise hold the potential to lower an individual’s risk for the disease by helping the body maintain functions that fight off infection, inflammation and the replication of damaged cells that can play a role in the development of malignant tumors.
Dr. John McCann is an oncologist with the Baystate Regional Cancer Program.