The circumferential resection margin in rectal carcinoma surgery

Abstract

After radical resection of rectal carcinoma, the circumferential resection margin (CRM) on the non–peritonealized surface of the resected specimen is of critical importance. Histopathological examination of resected specimens must include careful assessment of the CRM. There is a need to distinguish between CRM–positive (CRM directly involved by tumor or minimal distance between tumor and CRM 1 mm or less) and CRM–negative (distance between tumor and CRM more than 1 mm) situations. Optimized surgery (so–called TME surgery) and an experienced surgeon decrease the frequency of CRM–positive specimens. The CRM status is an important predictor of local and distant recurrence as well as survival. The CRM status can be reliably predicted by preoperative thin–slice high–resolution magnetic resonance imaging (MRI). In the event of predicted CRM–positivity, neoadjuvant radiochemotherapy is indicated.