Dr Liam Welsh is a Consultant Clinical Oncologist with specialist expertise in the management of adults with central nervous system tumours.

He read Natural Sciences at the University of Cambridge, graduating in Physics before completing a PhD in Biophysics in 1997. Following postdoctoral research in the Department of Biochemistry at Cambridge, he entered medical training and graduated from the Guy’s, King’s and St Thomas’ School of Medicine, University of London, in 2004 as proxime accessit to the University of London Gold Medal.

After core medical training in London, he undertook specialist training in clinical oncology at The Royal Marsden Hospital and at Guy’s and St Thomas’ Hospitals. During this period he completed an MSc in Oncology at The Institute of Cancer Research in 2012 with distinction. He went on to complete two years of clinical research in functional imaging in head and neck cancer at The Institute of Cancer Research/Royal Marsden Hospital, culminating in the award of an MD(res) in 2017. He gained Fellowship of the Royal College of Radiologists (FRCR) in 2011 and completed specialist training in 2015.

Dr Welsh was appointed as a Consultant in Clinical Oncology at The Royal Marsden in 2015 and has led the Neuro-Oncology Unit since 2018. He has a substantial research profile with numerous peer-reviewed publications and extensive involvement in national and international neuro-oncology research. He is a key investigator on landmark clinical trials, including the phase III INDIGO and STELLAR studies, supporting the development of advanced systemic and targeted therapies for brain tumours. His research collaborations span translational and early-phase studies, working closely with colleagues in the Drug Development Unit at The Royal Marsden and The Institute of Cancer Research.

His clinical interests include IDH-inhibitor therapy for IDH-mutant gliomas, stereotactic radiosurgery, and the integration of advanced imaging in neuro-oncology.