Optimised surgery (so-called TME surgery) and high-resolution MRI in the planning of treatment of rectal carcinoma

Background: Since November 1998, we have applied the concept of total mesorectal excision (TME) to rectal carcinoma together with a standardised pathological quality assessment. Participation in the European MERCURY study [The MERCURY Study Group Radiology (in press), 2006] required us to establish the indication for neoadjuvant radiochemotherapy on the basis of an magnetic resonance imaging (MRI) scan. The aim of the present retrospective study is to evaluate the quality of the surgery, the efficacy of the MRI and the oncological outcomes achieved. Materials and methods: Between November 2001 and October 2005, 68 out of 109 patients with carcinoma of the rectum were submitted to radical surgery in curative intent and 23/68 (34%) were given neoadjuvant therapy. In an interdisciplinary study group, each patient was evaluated pre-operatively and post-operatively using standardised MRI and histopathological methods. Results: The quality of surgery was established on the basis of the pathological examination of the surgical specimen. The rates of incomplete mesorectal excision, intra-operative tumour cell dissemination and positive circumferential margins were all low at 4%, 7% and 3%, respectively. The effectiveness of MRI proved to be greatest in predicting the tumour status at the circumferential resection margin: in the admittedly limited number of patients it proved possible to correctly predict the tumour status for every patient. The assessment of the anatomic extent of the primary tumour and of the regional lymph node metastasis according to the TNM system, in contrast, was considerably less successful at 73% and 75%, and 37% and 57%, respectively. Conclusions: By applying the TME concept and MRI-based therapy planning, excellent results can be achieved and, at the same time, the number of patients requiring neoadjuvant treatment is considerably reduced.