BACKGROUND For residual gastric tumors (RT) found at the treated sites after endoscopic resections (ER), additional treatment options are additional ER, surgery or argon plasma coagulation (APC). Long-term efficacy of APC as the curative modality for RT has not been fully elucidated. This study aimed to investigate the efficacy and long-term outcome of APC for RT with relevant tumor factors.

METHODS Eighty-two patients who received ER for gastric adenocarcinoma or adenoma and were subsequently treated with APC for RT were reviewed retrospectively. Characteristics of the tumors curatively ablated with single-session of APC and the non-curatively ablated were compared by multiple logistic regression analysis. Overall rate of curative ablation and follow-up duration was calculated.

RESULTS Initial tumor size <20 mm [odds ratio for second residual recurrence (OR) 0.16; 95 % confidence interval (CI) 0.039-0.63], en-bloc resection (OR 0.16; 95 % CI 0.039-0.72), histologic complete resection (OR 0.14; 95 % CI 0.028-0.66) and RT with flat or depressed type (OR 0.20; 95 % CI 0.051-0.77) were significantly associated with curative ablation of RT by single-session of APC. Anterior wall or lesser curvature location showed a tendency toward curative APC, but not reached statistical significance (OR 0.36; 95 % CI 0.11-1.16). A total of 60 patients (73.2 %) achieved curative ablation after single-session of APC. Eleven among the patients (n = 22) with second or more residual recurrence achieved curative ablation with one or two more additional sessions of APC. Overall rate of curative ablation was 86.6 % (71/82). From the last APC, the final curative ablation group (n = 71) has been followed up for 49.7 ± 37.4 months.

CONCLUSIONS En-bloc resection, histologic complete resection, RT with flat or depressed type and initial tumor size less than 2 cm can be predictors of favorable clinical outcome of APC as an additional treatment for RT. For selected patients with RT, APC and close monitoring could be a reasonable alternative to immediate resection.