Chen and his team were finally able to make the journey to Beijing thanks to the support from Wang Yung-ching, founder of the Chang Gung Medical Foundation and Formosa Plastics Group.

The girl's operation was a huge success, receiving praise as the largest medical emergency cooperation across the Straits. It marked the start of Chen's continuous cooperation with mainland counterparts.

In 2002, he and his mainland peers operated on a girl called Dong Guonyu from Shandong province who had been diagnosed with Wilson's disease, a genetic condition that prevents the body from removing excess copper, putting pressure on the liver.

Dong received part of her mother's liver during a tough 14-hour operation, which was carried out by 50 surgeons from both sides of the Straits.

Four years later, the patient and her parents visited Chen in Taiwan to express their gratitude. Today, Dong is the mother of a 10-year-old child.

In Chen's office there is a picture drawn by one of his child patients, Liu Mingrui. It's of a pair of hands tending to a heart, with the words "In love we become stronger" written above. Liu underwent a liver transplant led by Chen in 2006, when he was nine months old.

"When I was making a speech in 2014 in Shanghai, Liu came all the way to give me the picture. Now he is an excellent student and a runner for his school," Chen said.