Desley van Zoggel

Chapter 2 22 Methods Details of all patients with locally recurrent rectal cancer who underwent a resection at CatharinaHospital, a national tertiary referral centre for locally recurrent rectal cancer, between January 2010 and December 2016 were collected in a prospective database and reviewed retrospectively. A cohort of patients who had undergone reirradiation were selected, including thosewhohad full-course radiotherapy for either their primary tumour or a previous local recurrence. Patients with unresectable distant metastatic disease at presentation were excluded. At the start, these patients were deemed unresectable with regard to achieving clear margins; later, more ‘regular’ patients with locally recurrent disease were also selected. Patients who did not receive ICT but only concurrent CRRT, were used to compare the primary endpoints of pCR, clear margin (R0) rate, overall survival (OS), local recurrence-free survival (LRFS) and metastasisfree survival (MFS). Treatment and imaging regimen The general treatment regimen for the ICT group (Figure 1) consisted of three cycles of CAPOX (capecitabine and oxaliplatin) or four cycles of FOLFOX (leucovorin, fluorouracil and oxaliplatin), after which tumour response was evaluated by MRI and/or PET–CT. The presence of systemic disease was evaluated with CT or PET-CT. Referring hospitals were advised to administer three cycles before CRRT. When a good response was noted, continuation of chemotherapy with three cycles of consolidation chemotherapy in the waiting time after CRRT was advised. Some patients received six cycles of chemotherapy before CRRT. If no response to the first three cycles was noted, consolidation chemotherapywas considered not to be useful when administered in the waiting period. CRRT consisted of 30–30.4 Gy in fractions of 2–1.8 Gy with concomitant capecitabine (825mg/m2 twice daily) in all patients. Resectability and timing of surgery The waiting period between radiotherapy and surgery was generally 8–10 weeks. The tumour was restaged with MRI one month after the last radiotherapy administration to determine response and local resectability, and metastatic disease was excluded by CT or PET–CT. All patients were discussed in a multidisciplinary board meeting, and two senior surgeons with 20 years of experience in recurrent rectal cancer surgery performed all resections, as described previously.16