Dr Clarence Kerrison

MBChB  ·  MBioMedSci (Hons)  ·  FRACP
Consultant Gastroenterologist & Interventional Endoscopist · Waikato Public Hospital
Endoscopy on Clarence · Locum Tauranga Hospital · Locum Rotorua Hospital
Information website
Last updated 6 April 2026
About
Gastroenterologist and interventional endoscopist with a deep commitment to his patients, his communities, and advanced endoscopic outcomes.

Dr Clarence Kerrison was raised in Otamarakau, Bay of Plenty, and is of Ngāti Makino, Tūwharetoa and Ngāti Awa descent. He brings a strong sense of place and community to his clinical work, and works across a range of health settings and populations in Waikato and Bay of Plenty.

Dr Kerrison completed his medical training at the University of Otago, followed by specialist training in Gastroenterology and Hepatology across multiple hospitals in New Zealand. He then completed a fellowship in advanced interventional endoscopy at Westmead Hospital, Sydney, under Professor Michael Bourke — a world-renowned leader in advanced interventional endoscopy.

Dr Kerrison is a PhD candidate at the University of Sydney and is a member of Hei Ahuru Mōwai, the national Māori cancer leadership body, reflecting his commitment to equitable cancer outcomes for Māori and high needs populations.

More to come
Procedures & services
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Gastroscopy
Camera examination of the oesophagus, stomach and duodenum
Colonoscopy
Examines the entire lining of the large intestine for abnormalities, to diagnose conditions, or remove polyps
Bowel screening
National bowel screening programme for early cancer detection
Endoscopic mucosal resection (EMR)
Removal of superficial lesions using injection-assisted techniques
Endoscopic submucosal dissection (ESD)
En bloc resection of complex lesions with precision dissection
Complex polyp resection
Advanced removal of large or recurrent colorectal polyps
ERCP
Biliary and pancreatic duct diagnosis and therapy including stone removal and stenting
Endoscopic ultrasound (EUS)
High-resolution imaging with fine-needle aspiration capability
Fellowship & training
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2024 – ongoing
Research
University of Sydney
2023 – 2026
Advanced Endoscopy Fellowship
Westmead Hospital, Sydney
ESDEMRERCPEUS
2021 – 2023
MBioMedSci — First Class Honours
University of Auckland
2022
FRACP
Fellow of the Royal Australasian College of Physicians
2007 – 2012
MBChB — Bachelor of Medicine & Surgery
University of Otago
Publications  16 peer-reviewed
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2026
Endoscopic resection-related duodenal strictures: prevalence, risk factors, management, and outcomes
Gauci JL, Medas R, Mandarino FV, Kerrison C, Whitfield A, Gupta S, Wang H, Sidhu M, Lam B, Bracken L, Perananthan V, O'Sullivan T, Cronin O, Williams SJ, Lee EY, Burgess NG, Bourke MJ
Endoscopy
Endoscopy
2025
Updates in the endoscopic management of colorectal polyps
Kerrison C, Burgess NG
Ind J Gastroenterology
First authorEndoscopy
2025
Margin thermal ablation eliminates size as a risk factor for recurrence after piecemeal EMR of large non-pedunculated colorectal polyps
Gauci JL, Mandarino FV, Kerrison C, Whitfield AM, O'Sullivan T, Gupta S, Lam B, Perananthan V, Cronin O, Lee EY, Williams SJ, Burgess N, Bourke MJ
Gut
Endoscopy
2025
Impact of margin thermal ablation after cold-forceps avulsion with snare-tip soft coagulation for nonlifting large nonpedunculated colorectal polyps
Mandarino FV, O'Sullivan T, Gauci JL, Kerrison C, Whitfield A, Lam B, Perananthan V, Gupta S, Cronin O, Medas R, Tate DJ, Lee EY, Burgess NG, Bourke MJ
Endoscopy
Endoscopy
2025
Prevalence of endoscopically curable low-risk cancer among large (≥20 mm) nonpedunculated polyps in the right colon
Gauci JL, Whitfield A, Medas R, Kerrison C, Mandarino FV, Gibson D, O'Sullivan T, Cronin O, Gupta S, Lam B, Perananthan V, Hourigan L, Zanati S, Singh R, Raftopoulos S, Moss A, Brown G, Klein A, Desomer L, Tate DJ, Williams SJ, Lee EY, Burgess N, Bourke MJ
Clin Gastroenterol Hepatol
Endoscopy
2024
Cold vs hot snare EMR for large (≥15 mm) flat non-pedunculated colorectal polyps: a randomised controlled trial
O'Sullivan T, Cronin O, van Hattem WA, Mandarino FV, Gauci JL, Kerrison C, Whitfield A, Gupta S, Lee E, Williams SJ, Burgess N, Bourke MJ
Gut
RCTEndoscopy
2024
EMR for large non-pedunculated colorectal polyps: safe and cost-efficient
Mandarino FV, Medas R, Gauci JL, Kerrison C, Whitfield A, Gupta S, Williams SJ, Lee EY, Burgess NG, Bourke MJ
Gut
Endoscopy
2024
Recalcitrant rectal stricture: novel endoscopic stricturotomy
Gauci JL, Medas R, Kerrison C, et al.
Endoscopy
Endoscopy
2024
Diverticular POEM for thoracic oesophageal diverticula
Gauci JL, Gupta S, Kerrison C, et al.
Endoscopy
Endoscopy
2023
Omental patch endoscopic closure after gastric GIST removal
Medas R, Gauci JL, Kerrison C, et al.
Endoscopy
Endoscopy
2022
The narratives of Māori referred for colonoscopy
Kerrison C, Cassim S, Weilert F, Scott N, Koea J
University of Auckland Library
First authorEquity
2022
Equity of access to liver and stomach cancer surgery for Indigenous patients in NZ
Gurney J, Sarfati D, Stanley J, Kerrison C, et al.
BMJ Open
Equity
2022
Equity of travel to access cancer surgery in New Zealand
Gurney J, Whitehead J, Kerrison C, et al.
PLoS One
Equity
2022
Past, present and future of liver cancer control for Māori
Clough S, Cleverley T, Kerrison C, et al.
NZ Medical Journal
Equity
2022
Low but increasing rates of IBD in Māori
Qiu M, Patel RN, Kerrison C, et al.
NZ Medical Journal
Equity