The prognostic significance of the circumferential resection margin in esophageal squamous cell carcinoma patients without neoadjuvant treatment

BACKGROUND: Circumferential resection margin (CRM) is very important in esophageal cancer, but its diagnostic criteria has not been unified. The College of American Pathologists (CAP) and the Royal College of Pathologists (RCP) provide two different criteria. The aim of this study is to evaluate the long-term prognostic significance of CRM status with different CRM criteria in esophageal squamous cell carcinoma (ESCC). METHODS: Influence of CRM status according to the CAP and RCP criteria on long-term survival of 838 patients with resected pT3 tumors and without neoadjuvant therapy was analyzed. Patients stratified into three groups on the basis of tumor distance from the CRM (CRM > 1 mm, 0-1 mm, and 0 mm) were also analysed. RESULTS: Positive CRM was found in 59 (7%) patients according to the CAP criteria and 317 (37.8%) patients according to the RCP criteria. Univariate and multivariate survival analysis showed that CRM status, according to three different criteria, was independent prognostic factor. However, subgroup analysis showed that the prognostic value of CRM status was limited to certain metastatic lymph node load. In pN0 subgroup, patients with CRM > 1 mm had better prognosis than patients with CRM 0-1 mm. Patients with CRM 0 mm had worse outcome than patients with CRM > 0 mm in pN1-2 subgroup. But CRM status had no prognosis value in pN3 subgroup. CONCLUSIONS: The CRM status is an important prognostic factor in ESCC patients, but this effect was limited to patients without or with less lymph node metastasis (pN0-2). In clinical practice, we recommend the 1 mm-three-tier criteria as it provides more prognostic value than the traditional two-tier criteria.