Ms Sarah Mills

Consultant Colorectal and General Surgeon


Ms Sarah Mills is a Consultant in Colorectal and General Surgery at Chelsea and Westminster Hospital and Honorary Clinical Senior Lecturer in the Department of Surgery and Cancer at Imperial College London.

Sarah was awarded her Doctorate, in 2005, for her work at St Mark’s Hospital, London, on the immunology of inflammatory bowel disease. She has an active interest in surgical research and has published widely in peer reviewed journals. She was appointed an Honorary Senior Lecturer in the Department of Surgery and Cancer at Imperial College London in 2016. Miss Mills is a JAG accredited endoscopist and is developing a specialist practice in interventional endoscopy and cutting edge techniques for treating complex polyps and early rectal cancers by minimally invasive and endoscopic methods. She also has a specialist interest in laparoscopic surgery for colorectal cancer, diverticular disease, and inflammatory bowel disease.

Her clinical interests are Colorectal and intestinal cancer, Crohnís disease and ulcerative colitis, diverticular disease and proctology.

Professional background


Ms Sarah Mills graduated from Oxford University Medical School in 1998 and undertook surgical training in Oxford, Melbourne and London. Prior to taking up a Consultant post at Chelsea and Westminster Hospital she undertook Specialist Colorectal Fellowships at the Royal Adelaide Hospital, Australia and St Mark’s Hospital, London.

Services provided to HCA


Ms Sarah Mills provides professional medical advisory services to The LOC and The Lister Hospital regarding the set-up and ongoing management of rapid assessment services for patients with suspected colorectal cancer. As part of this, she advises on the optimal pathway for the diagnosis and treatment of colorectal cancer patients in line with current best practice. The service also requires advice on setting up a telephone assessment triage tool for patients. Ms Mills also helps advise on new technologies that would support the growth and development of the colorectal services.

She also provides advice and support in the recruitment of clinicians and clinical staff to work with and develop the colorectal services. Her role also includes advising on an ongoing basis to ensure appropriate, efficient and continuing operation of all aspects of the Hospitalís colorectal services including auditing outcomes, advising on clinical governance matters, advising on the management and growth of the colorectal assessment and treatment services. This will also involve assisting in the preparation and implementation of policies and procedures for the services, and ensuring the pathway for patients meets the UK and European standards.

To support this, she will help provide clinical support and leadership to junior consultants and the clinical team, and assist in setting up an appropriate MDT (multi-disciplinary team).

Furthermore, Ms Mills will assist in marketing activities related to the services, including participation in drafting marketing materials and participation in seminars to promote the hospital and services in general.


Mr Oliver Warren

Consultant Colorectal and General Surgeon


Mr Oliver Warren is a Consultant in Colorectal and General Surgery at Chelsea and Westminster Hospital and Honorary Clinical Senior Lecturer in the Department of Surgery and Cancer at Imperial College London. He is a core member of the Chelsea and Westminster colorectal cancer MDT, endometriosis MDT, and inflammatory bowel MDT. In 2015 Oliver published his first book entitled ‘Going into Hospital? A guide for patients, carers and families’ which seeks to engage patients in their care throughout the entire pathway and help patients improve their quality of care directly. He has written over 70 scientific papers and book chapters on medical leadership, patient safety and surgical education.

His Clinical interests are Colorectal and intestinal cancer, Crohn’s disease and ulcerative colitis, proctology, hernia and abdominal wall reconstruction.

Professional background


Mr Oliver Warren qualified from Imperial College London in 2001. He gained his Doctorate in 2009 from Imperial College London and was awarded Fellowship of the Royal College of Surgeons in 2012, for which he was awarded the ASGBI Gold Medal for outstanding performance.

Prior to becoming a consultant, he undertook colorectal surgery fellowships at St. Mark’s Hospital, London, the Royal Prince Alfred Hospital, Sydney and was the 2013 Association of Coloproctology’s visiting fellow at the Cleveland Clinic, Ohio, USA. He was appointed a Consultant in Colorectal and General Surgery at Chelsea and Westminster Hospital and Honorary Clinical Senior Lecturer in the Department of Surgery and Cancer at Imperial College London in 2015.

In April 2016 he became Service Director for General, Colorectal, Emergency and Vascular surgery at Chelsea and Westminster Hospital.

Services provided to HCA


Mr Oliver Warren provides professional medical advisory services to The LOC and The Lister Hospital regarding the set-up and ongoing management of rapid assessment services for patients with suspected colorectal cancer. As part of this, he advises on the optimal pathway for the diagnosis and treatment of colorectal cancer patients in line with current best practice. The service also requires advice on setting up a telephone assessment triage tool for patients. Mr Warren also helps advise on new technologies that would support the growth and development of the colorectal services.

He also provides advice and support in the recruitment of clinicians and clinical staff to work with and develop the colorectal services. His role also includes advising on an ongoing basis to ensure appropriate, efficient and continuing operation of all aspects of the Hospital’s colorectal services including auditing outcomes, advising on clinical governance matters, advising on the management and growth of the colorectal assessment and treatment services. This will also involve assisting in the preparation and implementation of policies and procedures for the services, and ensuring the pathway for patients meets the UK and European standards.

To support this, he will help provide clinical support and leadership to junior consultants and the clinical team, and assist in setting up an appropriate MDT (multi-disciplinary team).

Furthermore, Mr Warren will assist in marketing activities related to the services, including participation in drafting marketing materials and participation in seminars to promote the hospital and services in general.

HCA UK is charged by doctors in return for their expertise and advice, including on how to operate safe hospital facilities delivering complex care.

All services provided under this agreement are charged to HCA UK. From 1 January 2018 to 31 December 2018, the total amount charged by Sarah Mills and Oliver Warren was £23,478.

HCA requires the doctors that advise us to attest that if they also practice in the NHS that they are not compromising their NHS commitments.

The information disclosed on this page in accordance with the Private Healthcare Market Investigation Order 2014 is true and accurate to the best of HCA’s knowledge and belief.