Next steps in surgical colorectal cancer care Optimising efficacy and reducing morbidity

This thesis aims to discuss several surgical strategies in patients with colorectal cancer, from the perspective of optimising efficacy and reducing morbidity. In Part I, we focussed on the utility of an omentoplasty for improving the postoperative course of rectal cancer patients that underwent excision of the anorectum (APR), and learned that omentoplasty does not promote wound healing nor reduce risk of secondary infection. Actually, omentoplasty appeared associated with an added risk of complications such as perineal hernia, or chronic sinus if not properly performed. In Part II, we addressed other perineal wound closure strategies following APR. Although use of a prophylactic biological mesh lowered the incidence of perineal hernia, there was no impact on wound healing problems. Thus, a new strategy was proposed to enhance primary wound healing after APR using a small gluteal turnover flap. Final conclusion on the efficacy of this method cannot yet be drawn, but from this thesis one may conclude that the technique appears safe and feasible for routine closure after APR. Lastly, while the first two parts of this thesis have focussed on the surgical aspect of the treatment, Part III depicts the feasibility of utilising surgical resection to guide systemic therapy in colorectal cancer care. From the research of this thesis we may conclude that it appears feasible to establish patient-specific drug profiles using tumour organoids derived from surgical resection specimens, but several technical limitations need to be overcome before clinical implementation is warranted.