Mr Gregory Thomas


Consultant Colorectal Surgeon


Mr Gregory Thomas is a consultant colorectal surgeon at St Mark’s Hospital. He has a specialist interest in pelvic floor disorders, abdominal wall hernia, proctology and other areas of benign colorectal pathology.

He qualified from Imperial College School of Medicine (St Mary’s Hospital) in 2003 with distinction in surgery and an intercalated BSc from Imperial College, London. His basic surgery training was undertaken in the northwest London region with further specialist training in southwest London and Surrey and at St Mark’s Hospital.

During his training, he undertook two years of research into pelvic floor disorders at St Mark’s Hospital and was awarded an MD (Res) from Imperial College, London. He has maintained a strong research interest in this field. He has published around 40 peer reviewed papers and four text book chapters on pelvic floor and colorectal disorders. He has presented widely on these subjects at national and international meetings. 

He was awarded a travelling fellowship from the Association of Coloproctology of Great Britain and Ireland in 2016, and has spent time at the Cleveland Clinic Hospitals in Florida and Ohio USA, and at the Centre Hospitalier Universitaire de Nantes France. He was awarded the FRCS from the Royal College of Surgeons of England in 2016.

Prior to his appointment at St Mark’s Hospital, Mr Thomas was a consultant colorectal surgeon at Ashford and St Peter’s NHS Trust in Surrey.


Pelvic floor disorders
Abdominal wall hernia
Benign colorectal pathology

Recent publications

Randomized pilot study of anal inserts versus percutaneous tibial nerve stimulation (PTNS) in patients with faecal incontinence. CA Leo, GP Thomas, JD Hodgkinson, E Bradshaw, J Warusavitarne, J Murphy, CJ Vaizey. Accepted by Diseases of the Colon and Rectum.

Long term outcome of sacral nerve stimulation for faecal incontinence. CA Leo, GP Thomas, E Bradshaw, S Karki, S Hodgkinson, J Murphy, CJ Vaizey. 2020 sep 20. Doi: 10.111/codi.15369

Negative pressure therapy for stoma closure sites- a non-randomised case control study. N Obeid, E Sharma, M Dunstan, P Nisar, R Madani, HJ Scott, PE Bearn, GP Thomas. Int J Colorectal Dis. 2020 Sep 14. Doi: 10..1007/s00384

Insert devices for faecal incontinence. P How, PM Trivedi, PE Bearn, GP Thomas. Tech Coloproctol. 2020 Sep 1.doi:10.1007/s10151

Comparison between high resolution water perfused anorectal manometry and THD anopress anal manometry: a prospective observational study. CA Leo, E Cavazzoni, MMN Leeuwenburgh, GP Thomas, A Dennis, P Bassett, JD Hodgkinson, J Warusavitarne, J Murphy, CJ Vaizey. Colorectal Dis. 2020Aug:22(8):923-930

Small bowel obstruction secondary to diaphragmatic herniation following transabdominal cardiac ablation. E Sharma, C Bussa-Roa, A Sergot, K Ratnasingham, GP Thomas. Ann R Col  Surg Engl. 2020 Mar;102(3):e57-e59.

The Renew anal insert for passive faecal incontinence: a retrospective audit of our use of a novel device. CA Leo, GP Thomas, JD Hodgkinson, JP Segal, Y Maeda, J Murphy, CJ Vaizey. Colorectal Dis. 2019 Jun;21(6):684-688

Professional memberships


I am registered with all the major health insurers.

I am happy to see patients on a self paying basis.

My fee for an initial consultation is £280 and £150 for a follow up appointment.


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