PhD defence J.A.W. (Jan) Hagemans

The goal of this thesis was to focus on several aspects of treatment and further improve treatment of primary rectal cancer, locally advanced rectal cancer and locally recurrent rectal cancer. For cT4 rectal cancer, centralization in high volume hospitals seems to improve outcome. In patients with ILNM from primary rectal cancer cure by surgical resection is still an option. The proposed gluteal turnover flap seem promising to reduce perineal morbidity after abdominoperineal resection but needs further clinical research and the standard use of an omentoplasty after APR may not be necessary. In patients with LRRC, achievement of a radical resection margin is important, patients with a high chance on R2-resection should maybe be withheld from surgery and receive non–surgical palliative treatment. Patients with LARC and LRRC undergoing total pelvic exenteration experience considerable morbidity but quality of life increases after surgery, and elderly should not be withheld from total pelvic exenteration on age only. In patients undergoing total pelvic exenteration, a colon conduit avoids the risk of ileo-ileal leakage and may be a feasible alternative for an ileal conduit in patients receiving an end colostomy. Future and current studies regarding organ preserving therapy and watchful waiting are promising as less invasive treatment strategies. In addition, the use of induction chemotherapy in LRRC may be important to achieve a higher rate pathologic complete response and R0-resections. The use of liquid biopsy and ctDNA as a predictive or prognostic marker may be of great value in the near future, but further research is warranted.

Due to corona, the PhD defences do not take place publicly in the usual way in the Senate Hall of the Professor Andries Querido Room. The candidates will defend their dissertation either in a small group or online.