Risk factors for local recurrence in patients with positive lateral resection margins after endoscopic submucosal dissection for early gastric cancer

Abstract

Background: With the widespread use of endoscopic submucosal dissection (ESD) in patients with early gastric cancer (EGC), the number of cases with incomplete resection due to positive lateral resection margins (LM+) is increasing. Local recurrence, which occurs frequently in LM+ cases, is an important issue. This study aimed to clarify the clinicopathological factors related to tumor recurrence in LM+ cases after ESD for EGC. Methods: From January 2005 to December 2012, a total of 1,083 patients with EGC underwent ESD at our hospital. Of these, cases with a pathological diagnosis of LM+ were included in this study. Patients with positive vertical resection margins, those who underwent surgical resection immediately or were followed up for less than 6 months after ESD, were excluded. Results: A total of 55 LM+ cases after ESD for EGC were enrolled. Incorrect delineation of a lesion that extended pathologically beyond the ESD marking dots was the main cause of LM+. Local recurrence was found in 20 (36.4 %) patients (median follow-up period, 23 months). Local recurrence rates related to LM+ length were as follows: 7/29 (24.1 %) in 2 mm, 6/16 (37.5 %) in 4 mm, 1/3 (33.3 %) in 6 mm, 4/5 (80 %) in 8 mm, and 2/2 (100 %) in ≥10 mm. In multivariate analysis, tumor size >2 cm (OR 4.48, 95 % CI 1.18–16.99, p = 0.027), and LM+ length >6 mm (OR 7.65, 95 % CI 1.15–50.70, p = 0.035) were independent risk factors for tumor recurrence. Conclusion: To decrease the risk of LM+, it is highly important to accurately delineate the lateral margins during ESD; when the final histopathological result is LM+, cases with LM+ length >6 mm or tumor size >2 cm should be considered for additional surgical resection or re-ESD because of a high risk of tumor recurrence.