Key Points
- Professor David Cranston is the clinical director of the high-intensity focused ultrasound unit at the University of Oxford.
- His team explores the use of focused ultrasound to treat uterine fibroids, sarcomas, and cancers of the kidney, liver, and pancreas.
David Cranston, MB. ChB., MA, D.Phil, FRCS Eng, FRCS Ed, is the clinical director of the high-intensity focused ultrasound unit and Emeritus Associate Professor of Surgical Sciences at the University of Oxford. He has worked in focused ultrasound for more than 20 years and was integral to securing the first Chinese focused ultrasound device in the Western world. He has since researched the technology’s potential to treat many tumors, including uterine fibroids and cancers of the kidney, liver, pancreas, and sarcomas.
In the following Q&A, Prof. Cranston further describes his background, basic and clinical research projects, and vision for the future of therapeutic ultrasound.
Tell us about your background.
After completing my medical degree in Bristol and my surgical training in Exeter and Bath, I was appointed to a research post in Oxford under the guidance of Professor Sir Peter Morris, Nuffield Professor of Surgery. There, I completed my Doctorate in Philosophy on “Donor Induced Suppression in Renal Transplantation.” In 1991, I was appointed as a consultant surgeon in urological surgery and renal transplantation at Oxford University Hospitals and was joint supervisor to 14 research fellows studying for their MD or DPhil degrees on bladder and kidney cancers and laser treatment of benign prostatic enlargement. In 1999, I traveled with a group of colleagues to China to forge a relationship with Chongqing Medical University and the Chongqing HAIFU group. This collaboration is ongoing, and four more Oxford fellows have obtained their research degrees in this technology. I was made associate professor of surgery at the University of Oxford in 2007 and a Fellow at Green Templeton College Oxford that same year. From 2017-2023 I was President of the International Society of Minimally Invasive and Virtual Surgery.
How did you get interested in focused ultrasound?
In 1993, I initiated the Oxford laser prostate trial. I was awarded £100,000 to investigate the role of contact laser treatment of the prostate compared with the standard-of-practice, called transurethral resection of the prostate (TURP), in association with the Health Services Research Unit at the Churchill Hospital in Oxford. This trial has been acknowledged as one of the best-randomized studies of a new treatment for benign prostatic hyperplasia in the world and an example of how to evaluate new technology in surgery. One of the key people involved in this research was David Wild, and it was his interest in the potential of focused ultrasound technology in 1999 that facilitated the start of the Oxford program. We were then introduced to Professor Tim Mason, Professor of Ultrasonics at Coventry University, who connected us with Professor Zhibiao Wang, Professor Feng Wu, and the HAIFU team linked to Chongqing Medical University in China.
Following that, in 2000, I was the lead coordinator in a major research project on high-intensity focused ultrasound (HIFU). This role involved developing links in China with Chongqing Medical University and working with collaborators on clinical trials for liver and kidney tumors. This work resulted in the CE mark for the Haifu JC machine for Europe in 2005.
What are your areas of interest in focused ultrasound?
I am interested in all clinical applications of focused ultrasound. The extracorporeal Chongqing machine that we have at Oxford is licensed for the treatment of all abdominal tumors and benign uterine fibroids. We have also been involved in trials of kidney cancer, liver tumors, pancreatic cancer, and sarcomas, and we have treated some abdominal metastases from colorectal carcinoma. Oxford has treated prostate cancer with HIFU on a different machine in trials, and we have treated benign uterine fibroids on the Chongqing device. I work closely with Professor Constantin Coussios and his team, who are investigating clinical indications for oncological drug delivery and immune modulation across the liver, kidney, and pancreas; thermal ablation and cavitation-enhanced thermal ablation of the liver, kidney, and pancreas; and emerging applications of cavitation-mediated delivery, including intracellular and transdermal drug delivery.
Oxford has established itself as one of the leading international academic centers for clinical and preclinical HIFU research. The research program initially centered on the HIFU unit at the Churchill Hospital and is now expanding into a number of laboratory-based projects around the University, in both the translational and clinical settings.
What is the goal of your work?
My goal is always to remain patient-focused and to make sure the treatment for the disease minimizes harm.
What are your funding sources?
Our initial funding was from Ultrasound Therapeutics Ltd. My team of research fellows have also been awarded grants from the Royal College of Surgeons of England, the Oxford-based urological charity Ucare, and charities dedicated to sarcomas and the pancreas. We have also received strong support from the UK’s National Institute for Health and Care Research (NIHR) and from several charities, including Cancer Research UK, and from generous private donors.
Who are your team members?
In the early days, I worked alongside Professor Feng Wu, David Wild, and James Kennedy. We supervised the creation of the first purpose-built center for HIFU at Churchill Hospital. That center opened in July 2002 under Professor Sir Peter Morris, President of the Royal College of Surgeons of England. Professor Wu has remained a key member of the Oxford team since.
I also work closely with Professor Gail ter Haar from the Institute of Cancer Research in London.
At Oxford, I have close collaborations with Professors Constantin Coussios, Eleanor Stride, and their teams of postdoctoral and doctoral researchers.
Dr. Paul Lyon, a consultant radiologist who worked with Professor Coussios on targeted drug delivery for liver tumors, is now co-director of the clinical side of the work in Oxford, and Dr. Priyanka Reddy recently joined the team to add her expertise as a consultant radiologist specializing in gynecology. Professor Feng Wu has been an integral member of the Oxford Team since the work started over 20 years ago and remains key to the ongoing clinical work.
Many of the consultant colleagues in the Oxford University Hospital Foundation Trust have been helpful and supportive over the years and continue to work with us in the clinical setting.
Who are your internal and external collaborators?
Internally, we collaborate extensively with the immunology group in the Nuffield Department of Surgical Sciences and the Department of Oncology. I also work with Prof. Coussios, Prof. Stride, and Prof. ter Haar.
Externally, we have been closely associated with Chongqing Medical University and the Chongqing HAIFU company for roughly 20 years.
How many patients have you treated?
We have treated over 400 patients with focused ultrasound, both in benign uterine fibroids and clinical trials for the liver, kidney, and pancreas, sarcomas, and drug delivery from thermosensitive liposomes (TarDox).
What are your greatest achievements?
Our greatest achievement is the close connection with Chongqing. It allowed us to obtain the first Chinese machine in the Western world.
In 2019, we received National Institute for Health and Care Excellence (NICE) recognition for benign uterine fibroids. More recently, Prof. Lyon and Prof. Coussios led the successful treatment of nine patients with metastatic colorectal cancer in the world’s first clinical trial of cavitation-enhanced drug delivery from sonosensitive particles. This built on the successful completion of the first in-human trial of extracorporeally triggered oncological drug delivery and was published in Lancet Oncology in 2018.
What do you see as impediments to your success?
A major problem that needs to be overcome is to get focused ultrasound treatments more widely accepted in the United Kingdom. This will happen as more machines become available and more trials are carried out. It would be helpful to get wider acceptance for benign uterine fibroids in particular and to get this commissioned as a National Health Service (NHS) treatment.
Has the Focused Ultrasound Foundation played a role in your work?
I am delighted that the University of Oxford has just been named a Foundation Center of Excellence. This designation will help us to continue with ongoing advancements in the treatment of patients and the development of more clinical trials.
What is on your research wish list?
To have the funding for ongoing research fellows and further clinical trials.
What’s next for you?
We are currently exploring the immunological effects of HIFU and working closely with Dr. Fadi Issa and others in the immunology labs at the Nuffield Department of Surgical Sciences. Further trials of targeted drug delivery and other applications for focused ultrasound are planned, and we are hoping that increased NICE approval for various treatments will be on the horizon.