Cellular Source Of Peritoneal Free Cancer Cells During It Reconstructive Surgery After Gastrectorny For Gastric Cancer.

e15063 Background: We have recently shown that viable cancer cells spilled into peritoneal cavity during curative gastric cancer (GC) surgery more frequently in cases with advanced tumor invasion and lymph node metastasis. In addition, 2.8% of early GC without any vessel invasions showed viable cancer cells in the peritoneal cavity during surgery, suggesting the presence of other channels for the spilling of cancer cells. Laparoscopic distal gastrectomy (LDG) with intracorporeal reconstruction has been applied according to advances in surgical techniques. However, oncological evaluation of LDG may not be fully performed. In this study, we examined the possibility of spilling cancer cells into the peritoneal cavity during the surgery for alimentary reconstruction in GC. Methods: Patients with open distal gastrectomy (n=37) or laparoscopic assisted distal gastrectomy (n=73) for GC were prospectively evaluated cytological examination of remnant stomach just before alimentally tract reconstruction. Ki67 staining was examined for the proliferative activity of detected cells. Results: Cancer cells were detected in 25 (22.7%) of 110 remnant stomachs of the patients received gastrectomy just before reconstruction. According to the depth of tumor invasion, incidence of cancer cell detection in patients with mucosal (m), submucosal (sm), proper muscle (mp), subserosal (ss), or serosal (se) tumor invasion was 1/28 (3.6%), 4/23 (17.4%), 4/15 (26.7%), 8/17 (47.1%), or 8/27, (29.6%), respectively. Cancer cells detected formed clustering. All of cases with cancer cells showed positive for Ki67 staining, indicating having proliferative ability. Incidence of cancer cell detection in the remnant stomach was significantly more in differentiated type than in undifferentiated type (p < 0.05). Conclusions: Viable and proliferative cancer cells present in the remnant stomach at the reconstruction of alimentary tracts after gastrectomy for GC. The prevention from spilling out cancer cells into peritoneal cavity should be seriously considered. Complete laparoscopic intracorporeal reconstruction should be accessed carefully from the oncological points of view as well as minimally invasive view.