Dr. Robert Chang is a consultant colorectal surgeon in the Section of Colorectal Surgery, Department of surgery, Jose R Reyes Memorial Medical Center. He served as the Director of Colorectal Surgery Fellowship program in the same hospital from 2001-2013, and as Chief of Section of Colorectal Surgery from 2005-2013.

Dr. Chang was President of the Philippine Society of Colon and Rectal Surgeons from 2013 to 2014.

His main scientific focus is on rectal cancer surgery. Among his contributions were the introduction of TME, pathologic evaluation of the quality of rectal cancer operations, and lateral pelvic node dissection.

Currently, with a growing interest in inflammatory bowel disease, heconsiders himself a neophyte IBD surgeon.