Dr Sarker is a Senior Lecturer and Honorary Consultant in Medical Oncology at Guy's and St Thomas' NHS Foundation Trust, and King's College Hospital NHS Foundation Trust. He specialises in the treatment of hepato-pancreatic-biliary malignancies: Liver Cancer, Bile Duct Cancer, Pancreatic Cancer, Neuro-endocrine Cancer, Adrenal Glands Cancer and Gall Bladder Cancer.

His main research focus is in the development of novel therapies for cancer, and together with Dr James Spicer, runs the Early Phase Clinical Trials Unit based at Guy's Hospital. He is also actively involved in the management of hepato-pancreatic-biliary malignancies at King's College Hospital Liver Unit, and has a specific interest in the development of new therapies and molecular imaging for these tumours.

Dr Sarker graduated in medicine from the University of Liverpool in 1997, and subsequently trained in internal medicine and medical oncology. In 2003 he was appointed to a Cancer Research UK Clinical Research Fellowship in the Drug Development Unit of The Royal Marsden Hospital and Institute of Cancer Research, leading to the award of a PhD. He completed his medical oncology training at The Royal Marsden in 2010.