To appeal to Chinese customers, world-famous medical institutions like the MD Anderson Cancer Center in the US began to have Chinese language information on its website. They have also set up teams to help foreign patients, including the Chinese, with doctor appointments and visas.

However, Cai said he does not consider that a challenge to his business.

"I couldn't be happier than to see more Chinese patients getting the best medical treatment worldwide," he said. "I hope Chinese doctors improve their capacity and then help the majority who cannot afford medical tourism with better treatment."

But some medical experts expressed caution over medical tourism, estimated to generate at least $60 billion worldwide.

"Given that medical tourism will probably stay in a regulatory void for a while, patients should be extremely careful choosing the right agency and consult Chinese specialists before making any decision," said Qiu Renzong, a leading bio-ethicist with the Chinese Academy of Social Sciences.

Chen Wanqing, deputy director of the National Central Cancer Registry and a senior cancer specialist, said he has seen more outbound tourism for cancer treatment among Chinese in recent years.

But he expressed doubt over the necessity of doing this.

For cancer treatment in terms of both surgery and internal medicine, "China could be neck and neck with most developed countries", he said.

However, "overseas hospitals might excel in hospital environment and patient services compared with the usually crowded Chinese hospitals", he said.

Those who can afford it, however, could try overseas, he said.

But "the patient should be careful with the long travel," he added.