Comment on recent publication : Surgical margin assessment in oesophageal cancer surgery is a controversial subject. Because the oesophagus is surrounded by vital anatomical structures (heart, airway, aorta) the boundaries of surgical resection are limited. Obtaining a clear margin is important for prognosis and this study demonstrates that the greater the margin, the better the prognosis. This goes a little further than judging margins in a binary fashion (positive / negative) according to the various classifications available in the literature (American College vs Royal College of Pathologists). It is important to remember that significant evidence points to the fact that margin +ve patients often recur with systemic metastases rather than isolated local disease. More radical surgery or the addition of radiotherapy is unlikely to alter the prognosis of this group and developments in systemic therapy will be important.
Background:
Previous analyses of the oesophageal circumferential resection margin (CRM) have focused on the prognostic validity of two different definitions of a positive CRM, that of the College of American Pathologists (tumour at margin) and that of the Royal College of Pathologists (tumour within 1 mm). This study aimed to analyse the validity of these definitions and explore the risk of recurrence and survival with incremental tumour distances from the CRM.
Methods:
This cohort study included patients who underwent resection for adenocarcinoma of the oesophagus between 2000 and 2014. Kaplan-Meier and Cox regression analyses were performed to determine the hazard ratio (HR) with 95 per cent confidence intervals for recurrence and mortality in CRM increments: tumour at the cut margin, extending to within 0·1-0·9, 1·0-1·9, 2·0-4·9 mm, and 5·0 mm or more from the margin.
Results:
A total of 444 patients were included in the study. Kaplan-Meier and unadjusted analyses showed a significant incremental improvement in overall survival (P < 0·001) and recurrence (P for trend < 0·001) rates with increasing distance from the CRM. Tumour distance of 2·0 mm or more remained a significant predictor of survival on multivariable analysis (HR for risk of death 0·66, 95 per cent c.i. 0·44 to 1·00). Multivariable analysis of overall survival demonstrated a significant difference between a positive and negative CRM with the Royal College of Pathologists’ definition (HR 1·37, 1·01 to 1·85), but not with the College of American Pathologists’ definition (HR 1·22, 0·90 to 1·65).
Conclusion:
This study demonstrated an incremental improvement in survival and recurrence rates with increasing tumour distance from the CRM.
