45.18 Predicting the Invasion Depth of Remnant Gastric Cancer

K. Tokizawa1, H. Takeuchi1, M. Inoue1, M. Takahashi1, K. Fukuda1, R. Nakamura1, K. Suda1, N. Wada1, H. Kawakubo1, Y. Kitagawa1  1Keio University School Of Medicine,Department Of Surgery,Shinjuku-ku, TOKYO, Japan

Introduction: To evaluate the adequacy of endoscopic treatment for remnant gastric cancer (RGC), we investigated the clinicopathological characteristics and the accuracy of preoperative prediction of the invasion depth of RGC.

Methods: We retrospectively surveyed 100 RGC patients who underwent surgical resection or endoscopic treatment in Keio University Hospital between January 2000 and June 2016.

Results: During the mentioned-above period, 75 patients with RGC underwent gastrectomy and 34 patients underwent endoscopic treatment, nine of whom underwent additional surgical resection after non-curative endoscopic treatment. Initial gastric diseases included benign (22 patients, 22.0%) and malignant diseases (78 patients, 78.0%). Reconstructions by initial surgery included Billroth I (69 patients, 69.0%), Billroth II (15 patients, 15.0%), and Roux-en-Y (one patient, 1.0%). Fifteen patients (15.0%) had underwent procedures other than distal gastrectomy. Among 85 cases with RGC following distal gastrectomy, the pathological depth of invasion was confined to the mucosa (M; 30 patients, 35.5%), submucosa (SM; 26 patients, 30.6%), muscularis propia (MP; 7 patients, 8.2%), subserosa (SS; 8 patients, 9.4%), and serosa-exposed (SE; 14 patients, 16.5%). In cases of pathological M, SM and MP, 41 patients (65.1%) had been properly diagnosed before the treatment. Preoperative prediction of the invasion depth was more invasive than pathological diagnosis in 9 patients (14.3%) and less invasive in 13 patients (20.6%). The accuracy rate was apt to be lower in anastomotic sites than in nonanastomotic sites (47.1% vs 71.7%, p = 0.065). Five-year survival rate in pathological stage I patients was not significantly different between patients who underwent endoscopic treatment and those who underwent surgical resection.

Conclusion: Endoscopic treatment may be reasonable option for early RGC. However, it requires careful consideration since there are still difficulties in making accurate preoperative prediction of the invasion depth of RGC.