Occurrence and prognostic value of circumferential resection margin involvement for patients with rectal cancer

Total mesorectal excision (TME) was advocated owning to the reduction in local failure, while deficiency in pathologic details limited monitoring of surgical quality assurance. Here, we aimed to examine circumferential resection margin (CRM) by large tissue slice, discussing its rule in occurrence and relationship with prognosis, thus providing proof for the adoption of TME principles and the application of adjuvant therapy.

Specimens of 106 patients with rectal cancer, who underwent potentially curative resection from December 2001 to September 2002, were examined. Follow-up data were collected.

Altogether, 2,068 mesorectal nodes were examined with 272 involved by tumor. CRM involvement (CRMI) was examined in 20 specimens. In these 20 cases, seven, nine, and four were caused by tumor infiltration, lymph node metastasis, and both, respectively. Occurrence of CRMI was more common for lower-located cancers while also statistically related to tumor differentiation, infiltration, and lymph node metastasis. The difference in local recurrence rate, general recurrence rate, disease-free survival rate, and overall survival rate between the group with CRMI and the group without were all proven to be significant.

Detailed pathologic examination, including status of CRM, is advocated since it provides accurate prognostic information. Surgeons could maximize the probability of cure by following the principle of TME. Preoperative adjuvant therapy was essential for advanced staged and lower-located lesions, which implied likelihood of CRMI.