Benchmarking the treatment of locally advanced rectal cancer : a comparative analysis of combined modality treatment with the Dutch randomized TME study

Introduction Objective of this article is to evaluate the current multimodality treatment for locally advanced rectal cancer (LARC) and to gain more insight in tumour biology. Patients A group of 201 single institution multimodality treated LARC patients with T4 and T3 tumours growing less than 2 mm from the mesorectal fascia were compared with a second group consisting of 316 patients with a T3 resectable rectal tumour, included in the Dutch TME trial. Results Overall survival after 3 years was not diff erent (76% for TME, 67% for LARC, p = 0.071). Local recurrence rate (LR) was signifi cantly lower in TME patients than in LARC patients at 3 years: 5% and 17% (p = 0.0001). In 83% of the LARC patients a negative circumferential resection margin could be realised, compared to 75% of the TME patients (p=0.037). Both circumferential margin status and lymph node status were important outcome parameters in both groups. Conclusion In both groups circumferential margin involvement and nodal positivity are independent prognostic factors in local control and survival. Outcome for a LARC patient is similar to resectable TME patients in absence of these factors. However, when chemoradiation did not result in achieving tumour regression and subsequent negative resection margins and negative lymph nodes, prognosis of LARC patients is signifi cantly worse. Benchmarking the treatment of locally advanced rectal cancer 133