Dr. Tien's medical journey began at the University of Sydney, where he earned his degree. He then completed his foundational physician training in Sydney before specialising in Rheumatology in Melbourne. His expertise extends to scleroderma, as evidenced by his fellowship in the field. Dr. Tien is actively involved in research, contributing to the International Scleroderma Clinical Trials Consortium Damage Index Working Group. He has also shared his knowledge through presentations at local and international conferences.

Dr. Tien's clinical experience in Melbourne is vast. He served as a consultant at an Arthritis and Biologic Clinic, treating patients with various inflammatory conditions like rheumatoid arthritis, psoriatic arthritis, and ankylosing spondylitis. His focus has also encompassed osteoarthritis of the hip and knee, where he worked in a dedicated clinic. Dr. Tien's commitment to research is further highlighted by his participation in an NHMRC-sponsored study that compared synovial fluid in patients with rheumatoid arthritis and osteoarthritis.