Locally recurrent rectal cancer; long-term outcome of curative surgical and non-surgical treatment of 447 consecutive patients in a tertiary referral centre

The majority of patients with locally recurrent rectal cancer (LRRC) present with extensive metastatic disease or an unresectable recurrence, and will be treated palliatively. Only a minority of patients will be eligible for potential cure by surgical treatment. The aim of this study is to evaluate the long-term outcome of surgical treatment and non-surgical treatment of patients with LRRC. All patients with LRRC referred to our tertiary institute between 2000 and 2015 were retrospectively analysed. Patients were discussed in a multidisciplinary tumour board (MDT) and eventually received curative surgical or non-surgical treatment. Overall survival (OS) was compared by resection margin status and non-surgical treatment. A total of 447 patients were discussed in our MDT of which 193 patients underwent surgical treatment and 254 patients received non-surgical treatment. Surgically treated patients were significantly younger, received less neoadjuvant therapy for the primary tumour, had less metastasis at diagnosis and more central recurrences. The 5-year OS was 51% for R0-resections and 34% for R1-resections. Although numbers with R2-resections were too small to implicate prognostic significance, there was no difference in 5-year OS between R2-resections and non-surgical treatment (10% vs. 4%, p = 0.282). In a subgroup analysis the OS of R2-patients was even poorer compared to optimal palliative treated patients with combined chemotherapy and radiotherapy (22 vs 29 months, p = 0.413). R2-resections do not result in a survival benefit compared to non-surgical treatment in this non-randomized series. Patients with a high chance on a R2-resection could be offered non-surgical treatment, without local resection.