Nearly Half of Cancers Are Preventable, but Cancer Prevention Is a Systematic Social Project

On May 2, 2018, I was to take a train from Hangzhou Station back to Beijing. A gastric cancer patient whom I had followed for nearly two years came to Hangzhou Station to see me. We found an empty seat at the KFC in Hangzhou Station and sat down to talk.

Pointing to the stream of people outside the door, I said to him: "Look at this endless flow of people. About one in three of them will eventually die of cancer. Although some of them look healthy now, there is no escape for them."

At that moment, as we gazed at the bustling crowds at the entrance of Hangzhou Chengzhan Station, a feeling beyond words welled up in our hearts.

I am not exaggerating. Among the population of China's first- and second-tier cities, about one in three will eventually die of cancer. Overall, a little over one quarter of urban Chinese and a little over one fifth of rural Chinese will die of cancer. These figures come from the statistics of our national health authorities.

In the time it takes us to eat a meal, several hundred more people in China are diagnosed with cancer. Every day, more than ten thousand people in our country are diagnosed with cancer. And each year I probably come into contact with ten thousand cancer families.

Recently, the International Agency for Research on Cancer (IARC) of the World Health Organization (WHO) released its latest cancer report. It shows that the number of cancer patients worldwide is growing rapidly, with 18.1 million new cases in 2018 alone and as many as 9.6 million deaths.

Because my mother died of gastric cancer, I once resolved to study medicine and make treating cancer my life's work. But as I treated patient after patient, I found that the more I treated, the more patients there were.

Now I feel that calling on the public to take action and reduce the incidence of cancer is more meaningful than simply treating cancer.

In September, when I passed through Hangzhou again, this patient came to the West Lake to see me for a follow-up visit. His complexion was excellent; according to him, he was now the person with the best complexion in his entire family.

For him, gastric cancer was both a misfortune and a blessing. Had it not been for this illness, he would still be constantly abusing his body in work and life; whether he would be in such good health now is anyone's guess.

In Nanning there was a nurse who developed breast cancer when young and later lived past the age of one hundred. Once, when a reporter went to interview her, the old nurse said one thing: "If I hadn't had cancer, how could I have lived until now? I would have died long ago."

Some cancer patients—especially those with early-stage cancer—who live to a ripe old age really have cancer to thank. For it was cancer that woke them up, made them readjust their life goals, and gave them a second life.

Cancer is both a bad thing and a good thing for some cancer families. Precisely because someone in the family developed cancer, they begin to take cancer prevention seriously. If everyone knew how to live healthily, the incidence of cancer in our country would plummet.

Many of the cancer patients I have encountered are poor and sick, utterly pitiful. But they are both worthy of sympathy and not worthy of it. They deserve sympathy because they have now met with disaster in life; they do not deserve it because the chief culprit that brought this disaster upon them is themselves.

Nearly half of all cancers are preventable. The single greatest cause of cancer is population aging, but an individual's lifestyle and environment also greatly affect cancer incidence.

As per capita income and per capita life expectancy rise in our country, cancer incidence is clearly rising.

In the past, most people did not live past forty, and cancer is a disease of high incidence among people over forty. Therefore, rising life expectancy has directly driven up the prevalence of cancer in our country.

Income is also positively correlated with cancer incidence. According to Our World in Data, the higher the income, the higher the rate of cancer; among lower-income groups, the cancer rate is lower.

The "Guidelines on Nutrition and Physical Activity for Cancer Prevention and Survival" compiled by the American Institute for Cancer Research recommends that more than 80% of our food should come from plants.

The guidelines recommend that on five days each week, we ensure at least 50 minutes of moderate-intensity exercise or at least 30 minutes of vigorous-intensity exercise, in order to burn off excess calories and fat.

The guidelines also point out that smoking and excessive drinking are important causes of cancer. Controlling body weight and eating five or more servings of different vegetables or fruits each day can effectively prevent many cancers.

By these guidelines, most of us have unhealthy lifestyles. But merely doing this is far from enough when it comes to preventing cancer.

Take malignant melanoma, which has exploded in our country in recent years. It is a type of skin cancer with a high degree of malignancy and an extremely rapid course; many patients die within less than a year from discovery to death.

This cancer is linked both to the destruction of the ozone layer in our atmosphere and to the rising incomes of Chinese people, who increasingly love to travel.

For UV-A and UV-B bands in sunlight burn human skin, and such burning is the cause of most malignant melanomas.

In some countries and regions with a high incidence of malignant melanoma, volunteers, including doctors, actively take to the streets and the beaches to educate vacationers sunbathing, warning them to prevent malignant melanoma.

But at present, the public in our country does not yet have such a strong awareness of preventive medicine, nor is the spirit of volunteerism so developed. So over the past decade or more, the prevalence of malignant melanoma in China has risen more than tenfold.

I have treated a great many malignant melanoma patients over the years, most of them at an advanced stage. Malignant melanoma is extremely easy to detect, because most melanomas grow on the skin. But because the public lacks understanding of the difference between normal moles and junctional nevi, they often miss the window for early detection.

As for the prevention and early detection of malignant melanoma, I will write a dedicated article in the future; space here does not permit elaboration.

Public education can save lives. Doctors have the responsibility and obligation to popularize medical knowledge to society.

Unfortunately, China's medical system is not yet well developed; most doctors hold an "iron rice bowl," and few take the initiative to educate the public. Medical textbooks are both dull and obscure, and not many ordinary people are willing to read them.

In many countries, doctors do not belong to the "public" sector. They must build their own personal brands and develop their own patient bases, so they have a very strong incentive to keep learning and to popularize medical knowledge among the public. I hope China's healthcare reform will move in this direction.

Preventive medicine is what we lack most. Our country is a nation of gastric cancer; more than half of the world's gastric cancer patients come from China. Gastric cancer is also the fifth most common cancer and the third leading cause of cancer death in our country. Yet the work we have done on early screening and preventive medicine for gastric cancer remains limited.

About 59% of people in our country are Helicobacter pylori-positive. H. pylori is the greatest culprit behind gastric cancer; most gastric cancer patients have a history of H. pylori infection. This has much to do with Chinese eating habits—the shared-plate system is not valued here.

Among Buddhists, the H. pylori infection rate is the highest; among Tibetan Buddhist lamas in particular, over 90% are H. pylori-positive. Among Han Chinese Buddhists too, those testing positive for H. pylori are more numerous than in the general population. This is because within this group, long-term communal dining is common and tableware is not thoroughly disinfected.

H. pylori can be transmitted through shared meals and shared utensils. Once infected, some people develop symptoms such as functional dyspepsia, which gradually progress to gastric ulcer, intestinal metaplasia, or atrophic gastritis—precancerous lesions of gastric cancer.

Many cancers develop gradually from poor lifestyle habits or from certain chronic diseases.

In medicine there is a professional term called the point of no return. Before progressing to carcinoma in situ—even before precancerous lesions appear—by changing lifestyle and eradicating the carcinogenic cause, the process can be reversed so that the patient does not develop cancer. But once it has progressed to carcinoma in situ or a relatively severe precancerous lesion, it can hardly be reversed again.

This is why the American Institute for Cancer Research advocates that, from childhood, people should maintain good dietary, exercise, and sleep habits, cultivate good social skills, maintain a good interpersonal environment, and keep both body and mind healthy. Only in this way can cancer be prevented.

Americans were once nearly overwhelmed by cancer. Later the U.S. government elevated cancer prevention and control to a national strategy, calling on the whole nation to fight cancer and adopting a series of measures that valued the physical and mental health of the public. After that, U.S. cancer incidence stopped rising and began to decline year by year.

China has in fact already reached the point where the government should elevate cancer prevention and control to a national strategy. Medical students and doctors should step forward to popularize knowledge about cancer prevention among the public; volunteers should take to the streets, the beaches, and the villages to spread medical science; and every citizen should spontaneously take action to prevent cancer.

This is a systematic project requiring the joint effort of everyone, and in the end everyone benefits.

I am in Beijing, and many people invite me to join the big health industry. Social capital now stares at the cake of the big health industry with green eyes. But basically they are all focused on the treatment of major diseases such as cancer, because that is where the money is.

Many people shout about developing preventive medicine, but few actually do it. Instead, plenty of health-product salespeople hang out the sheep's head of preventive medicine while selling their own dog meat.

Chinese per capita income is actually not low now, and we have entered an era that genuinely needs preventive medicine. Preventing cancer can lower society's pain index and lighten the public's medical burden. Those with ambition should participate rather than stand by.

This road is long, but it is deeply meaningful.