Main Menu

Dr Ben O'Leary

Group Leader

The alt text
Ben O'Leary is a Clinician Scientist at the ICR and an Honorary Consultant in Clinical Oncology at The Royal Marsden hospital, working in the Molecular Oncology group. Group: Targeted Therapy
+44 20 3437 7415

Research overview

Ben's current research is focused on understanding the evolution of resistance to cancer therapies in breast and head and neck cancers.

In many patients with cancer it is possible to pick up traces of the cancer's DNA from a blood sample, known as 'circulating tumour DNA' or 'ctDNA'. Recently, the development of novel technologies have allowed us to detect and characterise this ctDNA to learn about a particular patient's cancer, offering opportunities to understand cancer biology and response to treatments. Circulating tumour DNA can also be used to track how a cancer evolves in response to treatment.

During his time in the Molecular Oncology group, Ben studied CDK4/6 inhibitors in breast cancer using circulating tumour DNA, identifying a number of mechanisms of resistance to commonly used breast cancer therapies. For this work he was awarded the Institute of Cancer Research Chairman's Prize, a Conquer Cancer Endowed ASCO Merit Award and the Royal College of Radiologists Ross Prize.

Dr O'Leary is a member of the Cancer Research UK Convergence Science Centre, which brings together leading researchers in engineering, physical sciences, life sciences and medicine to develop innovative ways to address challenges in cancer.

Convergence Science Centre


Ben's undergraduate training included Aerospace Engineering at The University of Cambridge and then Medicine at King's College London. In 2012 he commenced dual academic and clinical training with an NIHR Academic Clinical Fellowship in Clinical Oncology, working at The Royal Marsden hospital, The Royal Sussex County Hospital and The Institute of Cancer Research.

Ben was subsequently awarded a prestigious MRC Clinical Research Training Fellowship in 2015, which he undertook in Nick Turner’s Molecular Oncology group at The Institute of Cancer Research. In 2022, after completing an NIHR Academic Clinical Lecturer he was appointed as a Clinician Scientist at The Institute of Cancer Research and an Honorary Consultant in Clinical Oncology at The Royal Marsden hospital.