After spending about two months in California receiving medical treatment and recovering, 64-year-old Wu Ming finally bounced back to health.

Wu started to feel physical discomfort in 2012, but an examination in a local hospital in Shanghai showed nothing abnormal. It wasn't until September 2013 that he was diagnosed with late-stage prostate cancer.

Learning that traditional treatment would do little to the disease, Wu turned to Shanghai-based MEGA Healthcare in September 2014, and two months later received a particle therapy treatment in the United States.

Founded in March 2013, MEGA Healthcare helps people receive medical treatment overseas. Across China, the number of such agencies is nearly 30.

Wu is but one of an increasing number of Chinese willing to pay more for overseas healthcare and treatment. The number of people going abroad for medical treatment has doubled to 40 million in six years since 2006, and in 2013, their total spending reached $438.6 billion. This made up 14 percent of the global tourism industry, according to Xinhuanet.com, citing a survey released by the Stanford Research Institute in the US.

Chinese visits to South Korea for medical treatment soared nearly 17 times to 79,481 in five years from 2009 to 2014, the Chinese version of South Korean AJU Business Daily reported.

Chinese patients spent 140.3 billion South Korean won ($126.6 million) in 2014. They also topped the foreign patients list ahead of visitors from Russia, the US and the United Arab Emirates.

Other places are proving just as popular.