KENT Tsang Kam-sze has become the unsung hero of the bone marrow transplant programme at the Prince of Wales hospital in Sha Tin. As scientific officer, it is his job to liaise with the rest of the medical team in organising matching bone marrow. His role is often very much behind the scene but the work he carries out is crucial to the survival of the dozens of young people waiting for bone marrow transplants. He co-ordinates the transplant programme and likes nothing better than seeing one of his young patients leaving the hospital with a chance for a new life. ''There's about a 50/50 chance of success in the transplant operations but with more funding we could enhance our research and development programme.'' Mr Tsang said technology and medical breakthroughs throughout the world would be increasingly relied upon because of a change in the social network of Hong Kong. ''Families are getting smaller and the upshot is that we have less people to choose from when looking for a donor,'' he said.