Which Countries Have the Highest Rate of Lung Cancer?

But another important reason to ask this question is that it raises further questions. We know that smoking causes cancer, but the rates of smoking and lung cancer don't necessarily go hand-in-hand worldwide. Why? Why is there such a difference between countries with the highest rate of lung cancer overall, and the rate of lung cancer in women?

The causes of lung cancer are also called to the surface in this question. Globally, 80 percent of lung cancers in men are attributed to smoking, but only 50 percent of lung cancers in women are related to smoking. What are the causes of lung cancer in the other 50 percent of women, and could knowledge of this, and prevention measures where needed, make a difference for women in the United States as well? After all, the leading cause of cancer-related deaths in women in the U.S. is lung cancer, not breast cancer. In fact, there are more non-smoking women (never smokers and former smokers) who die in the U.S. each year from lung cancer, than women—non-smokers and smokers alike—who die from breast cancer.

And finally, while we are seeing a general leveling off or even decline in the overall number of people with lung cancer in the U.S., the incidence for one group is increasing: that of young, never-smoking women. Could looking globally help us answer that question?

Though tobacco awareness can and has made a tremendous impact at home and over the ponds, a look worldwide reminds us that our work on prevention and early detection, not to speak of better treatments, is far from done.

Hungary has the highest rate of lung cancer worldwide overall, while Denmark has the highest rate of lung cancer in women. Hungary follows a trend of many eastern European countries (with the exception of Romania) in which lung cancer has been increasing and continues to rise.

Hungary is an example in which smoking and lung cancer are correlated. Just as Hungary has the highest rate of lung cancer in the world, it also has one of the highest rates of smoking worldwide.

Yet even when smoking is a clear cause of lung cancer, such as in Hungary, it is important to consider other possible causes. Asbestos exposure is an added risk factor in Hungary, which contributes not only to lung cancer but the development of malignant pleural mesothelioma, a cancer which begins in the mesothelium, a membrane which lines the lungs.

Serbia has the 2nd highest rate of lung cancer in the world and is also a country that consistently has one of the highest rates of smoking worldwide.

This is not surprising given what we know about lung cancer and smoking since 50 percent of men (and 30 percent of women) in the country actively smoke. There are other factors beyond smoking, however, that may contribute to this rank. 

Some studies have found that exercise reduces the risk of lung cancer, and a recent study found that only 10 percent of men in Serbia engage in​ a regular physical activity. In Serbia, 50 percent of men are overweight, while a healthy diet may reduce the risk of lung cancer. Foods high in lutein (spinach, broccoli) and lycopene (tomatoes and tomato sauces) appear to lessen lung cancer risk while a high-fat diet raises the risk. Studies have also found that a high intake of some types of alcohol may raise lung cancer risk, and 40 percent of Serbian men consumed alcohol on a daily basis in one study.

Another factor that must be taken into account is the mortality rate from lung cancer once it has been diagnosed. With the economic situation in Serbia in recent years, medical care may not be equal to that of some other countries.

Korea (the Democratic Republic of Korea) has the 3rd highest rate of lung cancer in the world. There is a clear link between lung cancer and smoking in Korea, though many people have been surprised to hear of higher rates of lung cancer in some Asian women versus some European women, despite a lower rate of smoking. It's thought that indoor air pollution from unventilated coal-fueled stoves and cooking fumes contributes to an elevated lung cancer risk in some Asian countries. Secondhand smoke also appears to be a significant lung cancer risk factor in Korea, and other countries around the world. 

Heading east from Korea occurs something which has been coined as the Japanese lung cancer paradox. Why do American men have more lung cancer even though Japanese men smoke more (on average?)  There are several theories, though nobody knows for certain why this is true. It might be there are fewer carcinogenic (cancer-causing) ingredients in Japanese cigarettes than American cigarettes. Or perhaps genetic factors or diet lend Japanese men more resistance to the effects of tobacco smoke. Whatever the reason, this is a good reminder that cancer (all cancers) are usually a multifactorial disease, meaning that several factors work together to either cause or prevent cancer.

FYR Macedonia has the 4th highest rate of lung cancer in the world.

In addition to a significant number of smokers in Macedonia (around 40 percent of the population,) an early age at initiation of smoking (when someone starts smoking) has been considered a risk factor in this country.

Studies suggest that in addition to numbers of cigarettes smoked, and length of time someone smoked, the age at which smoking begins may raise lung cancer risk. This makes sense because those who begin smoking at an early age tend to do so during a period of rapid lung growth and development. Genetic studies have supported this theory, with evidence of long-standing physiological changes to DNA that lingers in smokers who begin their habit earlier in life.

In addition to smoking, occupational exposure to substances such as asbestos in an important cause of lung cancer in New Caledonia. In the United States, on-the-job exposures are thought to contribute to 13 to 29 percent of lung cancers, and this can vary widely worldwide.

Studies have found the men in New Caledonia who work as bus and truck drivers (diesel exhaust) as well as those who are exposed to cleaning products, inorganic fertilizers, and field dust have an increased risk of developing lung cancer.

New Caledonia, like Hungary, has a high incidence of pleural mesothelioma, which has been linked to the use of tremolite asbestos in whitewash.

Montenegro has the 6th highest rate of lung cancer in the world and also has one of the highest rates of smoking worldwide.

Studies looking at lung cancer in Montenegro highlight the clear association between smoking and lung cancer.  From 1976 to 2000, the rate of smoking in the country increased by 98 percent. During this same time period, the incidence of lung cancer in men nearly doubled, and that in women nearly tripled.

In addition, the types of lung cancer which are most common has changed in Montenegro. From 1997 to 2001, a significant increase in the incidence of small cell carcinoma was noted in both men and women, while the incidence of non-small cell lung cancer decreased. While smoking can contribute to any type of lung cancer, it is correlated most strongly with small cell lung cancer, and lung cancer that is found in never-smoking is very often non-small cell lung cancer.

Denmark has the 7th highest rate of lung cancer in the world. Part of this is truly a high rate of lung cancer, but Denmark also has an excellent system of record-keeping, making the ability to study cancer in this country more accurate.

Denmark is also a good example of how smoking awareness can save lives. The incidence of lung cancer reached its maximum in Denmark in 1985 and is now falling in men (though it continues to rise in women.)

In addition to smoking, there is a significant association between air pollution and lung cancer in Denmark. An increase in particulate matter air pollution, as well as road traffic, have been linked with risk, whereas traffic intensity on nearest streets and nitrogen oxides concentration does not appear to be correlated with risk.

The United States has the 8th highest rate of lung cancer worldwide, and lung cancer in both men and women is the leading cause of cancer-related deaths.

With smoking awareness, the incidence of lung cancer has begun to decrease in men and is leveling off in women.

Lung cancer screening for people who are eligible has recently been approved, and it is thought that screening could decrease mortality (the death rate) of lung cancer by 20 percent in the United States.

As with other regions of the world, there are risk factors beyond smoking, and anyone who has lungs is at risk. If you have never smoked, that is wonderful, but make sure to check out the causes of lung cancer in non-smokers to see if you can further reduce your risk.

Poland has the 9th highest rate of lung cancer in the world, a rate that is strongly linked with smoking.  In 1990 it was thought that 40 percent of Polish men died prematurely due to tobacco-related disease. The rate of smoking has decreased since that time.

The risk of lung cancer in Polish women is slightly different, with a family history of lung cancer playing a role in the incidence. For women in Poland, having a first-degree relative with lung cancer is linked with a significantly higher risk of developing the disease.

It also appears that women in Poland (and perhaps other regions of the world) are more susceptible to carcinogens in tobacco smoke than are men. Women in Poland tend to develop lung cancer at a younger age than men and after fewer cigarettes and fewer years of smoking. Women in the country are also more likely to be lifelong non-smokers.

Canada has the 10th highest rate of lung cancer in the world, and like the United States is an example of how tobacco awareness can save lives. Yet lung cancer is still the leading cause of cancer-related deaths in both men and women in Canada.

With the knowledge linking lung cancer and smoking and smoking cessation efforts, the incidence of lung cancer began to level off in the 1980's. A few years ahead of the United States in this progress, the rate of lung cancer for women has not increased since 2006.

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