Theo Wiggers was registered as a general surgeon in June 1984 after a surgical residency at the surgical department of the Academic Hospital Maastricht. After this period he specialized in surgical oncology and worked for 16 years in the Daniel den Hoed Cancer Center (DDHCC) and the University Hospital Rotterdam as the Head of the Department of Surgical Oncology. In June 2000, he continued his professional career as a Professor in Surgical Oncology at the University Medical Center Groningen (for several years also as the Chairman of the Department). He is consultant for the Comprehensive Cancer Center North in the Netherlands and a fellow of the Royal College of Surgeons (Eng.).

For many years, he was co-editor of the European Journal of Surgery and presently he is a member of the advisory board of the European Journal of Surgical Oncology. He served as the treasurer of the Board of the European Society of Surgical Oncology and was a member of the Dutch Governmental Committee for Oncology. From 2000 till 2008 he was one of the editors of the Cochrane Colorectal Cancer Group.

Clinically his main interest has been in pelvic and colorectal surgery coordinating several prospective clinical studies such as the No-touch isolation technique in colon cancer and the Dutch Total Mesorectal Excision trial. Research activities include also follow-up and imaging studies in rectal cancer, psychosocial studies related to coping strategies for cancer, continuity of information for cancer patients and motives and needs of patients seeking a second opinion.

Theo Wiggers was presented the 2010 ESSO Award as a result of his extraordinary efforts to improve the outcome of colorectal cancer patients. As Chairman of the department, first in Rotterdam and since 2000 in Groningen, he combined clinical research with education in trials and workshops resulting in improved outcome. He served the ESSO Board for many years and developed a masterclass to train (young) surgeons from all over Europe.