Neoadjuvant chemoradiation, precision oncological surgery and adjuvant chemotherapy in rectal cancer: time to be more selective in our approach

Abstract

Department of GI Surgery, University College London Hospital, London, UK Author for correspondence: manish.chand@uclh.nhs.uk **Author for correspondence: richard.cohen@uclh.nhs.uk Traditional prognostic factors remain the basis of tumor staging in rectal cancer – tumor depth (T); nodal disease (N); metastases (M). Since Pierre Denoix first proposed the TNM staging system in 1946 [1] much change has taken place in the management of rectal cancer, which perhaps today’s 7th edition of TNM [2] does not ref lect accurately. The most influential change has been the acceptance of a universal surgical technique – total mesorectal excision (TME) [3]. The surgical anatomy of the rectum is more complicated than that of the colon. It is the intimate relation to surrounding neurovascular structures within the narrow confines of the pelvis which makes surgical resection so challenging with regards to local recurrence and functional outcomes [4]. By precisely dissecting along embryological planes, the rectum and surrounding lymphovascular envelope is excised en bloc. Providing the tumor has not breached the mesorectal fascia, the disease and any affected local lymph nodes are effectively removed. This has led to local recurrence rates consistently below 5%. Technology has led to more novel methods of excision such as laparoscopy, robotics and transanal techniques all attempting to further improve oncological, functional and perioperative outcomes. But it is strict adherence to TME technique which underpins any surgical evolution. The increasing use of neoadjuvant treatment has further helped reduce local recurrence. Offering radiotherapy to patients before surgery has been shown to dramatically improve survival outcome [5]. This has been enhanced by the emergence of MRI to accurately stage