Introduction: Tumour size and the quality of its complete surgical removal are the main prognostic factors in rectal cancer treatment. The number of postoperative local recurrences depends on whether the mesorectum has been completely removed - total mesorectal excision (TME) - and whether tumour-free resection margins have been achieved.
The surgery itself and its quality depend on the accuracy of preoperative diagnosis and detection of risk areas in the rectum and mesorectum, on the surgeon's skills, and finally on pathological assessment evaluating whether complete tumour excision has been accomplished including circumferential margins of the tumour, and whether mesorectal excision is complete. The aim of our study was to implement and standardize a new method of evaluation of the quality of the surgical procedure - TME - in rectal cancer treatment using an assessment of its circumferential margins (CRO) and completeness of the excision.
Methods: The study consisted of two parts. The first, multi-centre retrospective phase with 288 patients analysed individual partial parameters of the diagnosis, operations and histological examinations of the rectal cancer.
Critical points were identified and a unified follow-up protocol was prepared. In the second, prospective part of this study 600 patients were monitored parametrically focusing on the quality of the TME and its effect on the oncological treatment results.
Results: The proportion of patients with restaging following neoadjuvant therapy increased from 60.0% to 81.7% based on preoperative diagnosis. The number of specimens missing an assessment of the mesorectal excision quality decreased from 52.9% in the retrospective part of to the study to 22.8% in the prospective part.
The proportion of actually complete TMEs rose from 22.6% to 26.0%, and that of nearly complete TMEs from 10.1% to 24.0%.