China has made major breakthroughs in the diagnosis and treatment of lung cancer, which is the top cancer killer in the country and around the world, according to a leading Chinese specialist in the field.

Because of the COVID-19 pandemic, more chest CT scans have been conducted in China for the diagnosis of lung diseases, leading to more early discoveries of lung nodules in patients and thus the detection of more early-stage cancer, Zhi Xiuyi, director of the Lung Cancer Diagnosis and Treatment Center at the Beijing-based Capital Medical University, told CGTN in an interview during this year's cancer prevention and treatment awareness week running from April 15 to 22.

Early detection is vital for the early treatment of lung cancer patients, which will help improve the cure rate significantly, according to the expert.

Meanwhile, lung cancer patients have been increasingly treated with minimally invasive surgery, especially thoracoscopy, which does much less harm to the body compared with open surgery in the past, he said.

The treatment cures more early-stage lung cancer patients and helps more elderly patients survive the surgeries, he noted.

In addition, with the wide use of genetic tests, which help detect the mutations in the DNA of cancer cells, target therapy and immunotherapy have been adopted to help more late-stage cancer patients survive longer and have better quality of life, the expert said.

In the past decade, China has made great progress in the treatment of lung cancer, especially in targeted therapy, which is the foundation of precision medicine that "targets" cancer cells without affecting normal cells, according to Zhi.

What's behind the high incidence of lung cancer?

Lung cancer was the second most common cancer worldwide in 2020 only after breast cancer, according to data from the World Health Organization.

Globally, there were 2.21 million new cases of lung cancer in 2020, accounting for 12.2 percent of the total number of new cancer cases diagnosed in the year.

In China, lung cancer ranked first in terms of both the incidence and death rate among all cancers, with 820,000 new cases and 710,000 deaths recorded in 2020.

Zhi cited several reasons for the high incidence of lung cancer, including the aging population, smoking, second-hand smoke and third-hand smoke, outdoor air pollution and indoor pollution like kitchen pollution, especially in China, where the cooking style mostly involves frying and stir frying, as well as psychological factors.

Zhang Jiangong, president of the Henan Cancer Hospital, further explained that outdoor and indoor pollution include asbestos, radon, soot and lampblack.

Besides, genetic factors also play an important role in the occurrence and development of lung cancer, he said.

Why is lung cancer the top cancer killer?

Lung cancer is still the leading cause of cancer deaths by far in China and the world.

In 2020, nearly 10 million people died from all kinds of cancer, among whom 1.8 million were killed by lung cancer.

China recorded 710,000 lung cancer deaths in the same year, which made up 23.8 percent of all cancer deaths in the country.

"The high death rate of lung cancer mainly results from the fact that it shows no symptoms in the early stage. Most lung cancers are diagnosed in the late stage, leaving no chance for surgeries. That is why regardless of nationality, lung cancer is the most lethal malignant tumor," Zhi told CGTN.

For lung cancer prevention, people should reduce exposure to risk factors like smoking, keep a healthy lifestyle, conduct regular cancer screenings and seek standardized diagnosis and treatment in hospitals in a timely manner once lesions are spotted, so as to realize early detection, diagnosis and treatment, according to Zhang.