Dr. Hiley holds the position of Associate Professor in Radiation Oncology at University College London (UCL) and serves as a Consultant Clinical Oncologist at University College London Hospital (UCLH). Additionally, he is the UK Clinical Director for Lung Cancer at Genesiscare.

Specialising in the application of stereotactic radiotherapy (SBRT) for oligo metastatic and oligo progressive diseases across various cancer types, Dr. Hiley's expertise includes a range of areas including breast, prostate, colorectal, gynaecological, sarcoma, and lung cancers.

As an authority in non-surgical treatments for lung cancer, Dr. Hiley excels in chemotherapy, immunotherapy, and state-of-the-art radiotherapy techniques. His proficiency extends to Volumetric Arc Therapy (VMAT), Intensity Modulated Radiotherapy (IMRT), Image Guided Radiotherapy (IGRT), Proton Therapy, and Stereotactic Radiotherapy (SBRT).

Dr. Hiley specialises in reirradiation, utilising radiotherapy for patients who have previously undergone radiotherapy, particularly in managing lung cancer and oligo metastatic and oligo progressive diseases across various cancer types.

Assuming his consultancy role in 2018, Dr. Hiley serves as the clinical lead of the clinical oncology lung team at UCLH. He also holds key positions such as UCLH Lead for Lung Proton Therapy, Deputy Lead of Clinical Trials for the CRUK Lung Cancer Centre of Excellence, NIHR Clinical Research Network Specialty Research Lead for Radiotherapy in North London, and Deputy Chair of the National Cancer Research Institute Lung Group.

At the UCL Cancer Institute, Dr. Hiley heads a dedicated research group focused on understanding resistance to radiation therapy. Notably, he serves as the chief investigator of the HIT-MESO study, investigating the role of hemi-thoracic proton radiotherapy for mesothelioma. Furthermore, he holds pivotal roles as the principal investigator and national chief investigator for several academic and commercial clinical trials in lung cancer.