Dr Leong graduated from the University of London in 2000. He obtained his membership to the Royal College of Surgeons of Edinburgh in 2003 and subsequently commenced working at theTan Tock Seng Hospital in Singapore. He began his Advanced Specialist Training in 2005 and passed his fellowship exams in 2008. In 2010, Dr Leong was awarded the prestigious MOH HMDP scholarship to train under Prof Kim Seon Hahn in Korea University for laparoscopic and robotic colorectal surgery. Following his return, he has been dedicated to advancing the practice of minimally invasive colorectal surgery.

In addition to laparoscopic colorectal surgery, Dr Leong performs a repertoire of minimally invasive general surgeries. He is trained in performing diagnostic and therapeutic scopes for elective and emergency surgical conditions. He performs direct access colonoscopies and oesophago-gastro-duodenoscopies for patients. Dr Leong is among a handful of surgeons in Singapore who practice single incision laparoscopic surgery for colorectal diseases. This is a highly technical procedure that confers improved cosmetic results. He also holds basic and advanced certifications in robotic colorectal surgery.

Dr Leong is dedicated to teaching others his methods for colorectal surgery and advanced laparoscopy. He routinely trains basic and advanced specialist trainees in laparoscopic surgery, and regularly proctors consultant surgeons in complex colorectal cases. He is an experienced surgical oncologist with a special interest in minimally invasive colorectal surgery. Dr Leong is also an endoscopist and accredited to train advanced surgical trainees in endoscopy.

Dr Leong accepts referrals for all cancer types, with a special clinical interest in surgery for colorectal cancer.