Jesper Lagergren is Professor and Chair of Upper Gastrointestinal Cancer at King's and Honorary Consultant of Surgery at Guy's and St. Thomas' NHS Foundation Trust. He is co-ordinator of the Programme in Gastrointestinal Cancer at KCL. In parallel, he is Professor and Consultant of Surgery at Karolinska Institutet and Karolinska University Hospital in Stockholm, Sweden, where he is member of the Nobel Assembly that awards the Nobel Prize in Physiology or Medicine.

Professor Lagergren received his MD in 1989, became a specialist in surgery in 1996, and got his doctorate in 1999. He became Professor in 2006 at Karolinska Institutet and in 2010 at King's.

Professor Lagergren has authored approximately 500 peer-reviewed articles, including approximately 300 with him as the last author. He has supervised 45 PhD candidates to completed theses, including 25 as main supervisor, and is currently supervisor of another 9 PhD candidates, including 7 as main supervisor. He has supervised 23 postdoctoral researchers.

His research focuses on the causes, prevention and treatment of oesophageal and gastric cancer and related disorders, e.g. gastro-oesophageal reflux disease, obesity, and Helicobacter pylori infection.