Prof. Lee is Clinical Professor and Head of Department of Clinical Oncology, University of Hong Kong and Chief of Service for the Center of Clinical Oncology and Deputy Hospital Chief Executive (Clinical Service) at The University of Hong Kong-Shenzhen Hospital in China. She is Honorary Professor of Peking Union Medical College Hospital. She is also the Honorary Consultant and Deputy Chief of Service of Clinical Oncology, Departments of Clinical Oncology at Queen Mary Hospital.

She is Vice President of Hong Kong College of Radiologists and the Vice Chairman of Hong Kong Anti-Cancer Society. She is the Coordinator of the Global Advisory Group and board member of Union for International Cancer Control (UICC) and a member of the TNM Expert Advisory Panel on Head and Neck Cancers; Vice-Chairman of the National Cancer Staging Committee of China.

Prof. Lee's main research contributions focus on nasopharyngeal cancer. Currently she is an Associate Editor for Oral Oncology, a member of the Board of Editors for Journal of Clinical Oncology, Radiotherapy & Oncology, and Clinical Oncology. She received the Sir Patrick Manson Gold Medal by The University of Hong Kong in 2008; Gilbert H. Fletcher Distinguished Professor Lecturer by The University of Texas, M.D. Anderson Cancer Center, United States, in 2009; Honorary Membership by the European Society for Radiotherapy & Oncology in 2012; Honorary Membership by the Radiological Society of North America in 2013; Wharton Lecturer by Princess Margaret Cancer Centre, Canada, in 2015; Alice Ho Miu Ling Nethersole Charity Foundation Professorship in Holistic Cancer Care by The University of Hong Kong since 2017; and Honorary Fellowship by American College of Radiology since 2019.