Total length of positive resection margins can predict remnant gastric cancer following endoscopic submucosal dissection.

ABSTRACT

BACKGROUND: Prediction of remnant tumor is important in determining subsequent treatment options for gastric cancer patients with positive resection margin (RM) after endoscopic submucosal dissection (ESD). METHODS: Based on the assumption that pathologic factors, including the length and type of involved RM, could potentially predict residual tumor, we evaluated 451 ESD specimens in patients with early gastric cancer. RESULTS: Of 408 cases, 37 (9.1 %) showed positive RMs. RM involvement in gastric cancer ESD specimens was associated with extended or beyond ESD criteria, greater tumor size, poor differentiation, submucosal invasion, lymphovascular invasion, and upper third location. Among the 37 positive RM cases, residual tumor was present in seven (18.9 %). The presence of residual tumor was not significantly associated with any clinicopathologic parameters except for tumor size and RM status. The total length of the involved RM was the most significant factor associated with the presence of residual tumor (P < 0.008). A total length cut-off value of 6 mm yielded a sensitivity of 85.7 % and negative predictive value of 94.7 % for predicting remnant tumor at gastrectomy following ESD. CONCLUSIONS: In conclusion, when the ESD specimen exhibits positive RM, a quantitative assessment of the involved RM should be included in the pathology report, as this can help the clinician predict remnant tumor and determine appropriate future treatment.