His expertise includes stereotactic body radiotherapy of liver and pancreatic cancer, and rectal brachytherapy. He has published peer-review journals and presented in overseas conferences. He is also the principal investigator of several ongoing prospective trials including, Sequential transarterial chemoembolization and stereotactic radiotherapy followed by Immunotherapy for downstaging hepatocellular carcinoma for hepatectomy (START-FIT trial) and Asian multi-center prospective phase II trial of external radiotherapy plus high dose rate brachytherapy in medically inoperable rectal cancer patients.