Professor Rule qualified from Nottingham medical school in 1987. Whilst still a medical student he intercalated and was awarded a Master of Philosophy degree for research into chronic myeloid leukaemia. He trained in Haematology in London at the Westminster and Hammersmith hospitals and also in Perth Western Australia. He is currently a Consultant Haematologist in Derriford Hospital Plymouth and Professor of Clinical Haematology at Plymouth University Peninsula Medical School.
Professor Rule is R & D director for Plymouth and is a member of the National Cancer Research Network (NCRN) lymphoma trials committee. He also sits on the clinical trials committees for both Cancer Research UK and Leukaemia and Lymphoma Research. He was previously the medical director of the peninsula cancer network and sat on the NICE cancer evaluation committee. His major interests are lymphoma, leukaemia and new drug development. His specific area of interest is in mantle cell lymphoma and he has a research team looking at various aspects of this disease. He is currently the chief investigator for a number of phase II and III lymphoma studies being conducted at local, national and international level. He is an author on over 80 publications.