Arend trained in General Surgery in Dunedin and Auckland gaining his Surgical Fellowship and a PhD on 'Occult Metastases in Colorectal Cancer' in 2001. Following this he completed a post fellowship training programme in Colorectal Surgery in Auckland and Oxford.
He has a particular interest and expertise in minimally invasive approaches to colorectal surgery, including laparoscopic surgery and single site laparoscopic surgery. His clinical interests are in colorectal cancer and inflammatory bowel disease with a special interest in the genetics of colorectal cancer and he is an advisor to the Northern Regional Familial Bowel Cancer Registry. In addition he is accredited in endoanal ultrasound and has an interest in the management of anorectal & pelvic floor disorders.
He is Director of General Surgical training at Auckland Hospital, author of over 40 peer reviewed articles and a supervisor of postgraduate students at the University of Auckland.
Arend is a member of the Colorectal Surgical Society of Australia & New Zealand and the Association of Coloproctologists of Great Britain and Ireland. Arend works as a Colorectal Surgeon at Auckland Hospital and in private practice at the Auckland Colorectal Centre and is an Honorary Clinical Senior Lecturer at the University of Auckland.