Desley van Zoggel

Chapter 6 102 Methods Patients All patients with LRRC who underwent a resection in the Catharina Hospital, Eindhoven – the Netherlands, a national tertiary referral centre for LRRC, are prospectively collected in a database. All consecutive patients with LRRC who underwent a resection with curative intent between 2010 and 2018 after treatment with induction chemotherapy followed by neoadjuvant chemo(re)irradiation were retrospectively selected. Patients for whom the baseline or restaging MRI was not available for reassessment were excluded. The study was waived by the local medical ethics committee (Medical Research Ethics Committees United Nieuwegein, registration number: W19.031). Figure 1. Flowchart showing patient selection Resection for LRRC (2010-2018) [N=313] Patients included [N=124] Exclusion due to - no induction chemotherapy [181] - no baseline or restaging MRI [8] Neoadjuvant and surgical treatment At the Catharina Hospital, Eindhoven – theNetherlands, all patients with LRRC receive neoadjuvant chemo(re)irradiation. In this selected cohort, all patients received induction chemotherapy before this. Induction chemotherapy generally consisted of four cyclesofCAPOX(capecitabineandoxaliplatin) or sixcyclesof FOLFOX(leucovorin, 5-fluorouracil, oxaliplatin). Initially, induction chemotherapywas reserved for patients with irresectable or marginally resectable disease. Gradually, the administration of induction chemotherapy became more common practice and finally became the local standard of care in 2016.13 In radiotherapy-naïve patients, full-course radiotherapy was delivered with a cumulative dose of 50-50.4 Gy. In patients who previously received pelvic radiotherapy, radiotherapy was delivered with a cumulative dose of 30-30.6 Gy. The concomitant chemotherapy agent was capecitabine (825 mg/m2 twice a day on radiotherapy days).