Hisayo Ueki

Predictive factors for lymph node metastasis of differentiated submucosally invasive gastric cancer

BACKGROUND For early gastric cancer, submucosal invasion may be unrecognized until histopathologic examination of the specimen obtained by EMR. Gastrectomy with lymphadenectomy is the standard treatment for such submucosal cancers. However, approximately 80% of submucosal cancers do not have lymph node metastasis. Unnecessary surgery could be avoided if a subgroup of patients with submucosal cancer with negligible risk of lymph node metastasis can be defined. This study was conducted to define such a subgroup. METHODS Data from 104 patients surgically treated for differentiated submucosal cancers were retrospectively collected. A multivariate analysis of clinicopathologic factors was performed to identify predictive factors for lymph node metastasis. RESULTS Three independent risk factors, namely, female gender (p=0.0174), deep invasion (> or =500 microm) into the submucosal layer (p=0.001), and presence of lymphatic involvement (p < 0.0001) were associated with lymph node metastasis. Lymph node metastasis was not observed in any patient who had limited submucosal invasion and absence of lymphatic involvement. The rate of lymph node metastasis was calculated to be 80% in patients who had both deep submucosal invasion and lymphatic involvement. CONCLUSIONS If endoscopic resection specimens exhibit no deep penetration (<500 microm) into the submucosal layer and lymphatic involvement is absent, EMR may be sufficient treatment for submucosal well-differentiated early gastric cancers. A long-term follow-up study of patients with such lesions treated by EMR alone is required.

Single-port endoscopic cholecystectomy: a bridge between laparoscopic and translumenal endoscopic surgery

BACKGROUND AND OBJECTIVE The intentional puncture of the normal viscera is likely the most important issue limiting the widespread use of natural orifice translumenal endoscopic surgery (NOTES). We developed a new procedure for cholecystectomy using a flexible endoscope via a single port placed in the abdominal wall without visceral puncture (single-port endoscopic cholecystectomy; SPEC) as a bridge between laparoscopic surgery and NOTES. This study aimed to evaluate the technical feasibility of SPEC. METHODS Five pigs were subjected to SPEC. An endoscope was inserted through a 12-mm port placed in the right upper abdomen. After grasping and retracting the gallbladder using a 2-mm retractor that was directly introduced into the peritoneal cavity, gallbladder excision with ligation of the cystic artery and duct using endoclips was carried out. RESULTS A complete gallbladder excision was carried out easily and safely in all cases. No major adverse events occurred. The mean operating time was 67 min (range 52-84 min). CONCLUSIONS SPEC is a technically feasible procedure. It is simpler, easier, and safer than NOTES cholecystectomy. SPEC could be a less invasive alternative to the conventional four-port laparoscopic cholecystectomy.

Cholecystectomy by a combined transgastric and transparietal approach using two flexible endoscopes

OBJECTIVE This experimental study was designed to assess the technical feasibility and benefits of our novel approach for transgastric NOTES (natural orifice translumenal endoscopic surgery) cholecystectomy. METHODS Four pigs were subjected to NOTES cholecystectomy by the combined transgastric and transparietal approach using two flexible endoscopes. Under the guidance of a transparietal endoscope inserted through a trocar placed in the right upper abdomen, a gastrotomy was constructed, and a peroral endoscope was advanced into the peritoneal cavity through the gastrotomy and moved on retroflexion toward the gallbladder. Gallbladder excision with ligation of the cystic artery and duct using endoclips was performed using the peroral endoscope. After gastrotomy closure with endoclips inside the stomach, intraperitoneal lavage were carried out using the transparietal endoscope. RESULTS A complete gallbladder excision was carried out without major adverse events in all cases. The gastrotomies were successfully closed using endoclips (n = 3) or by the omentum-plug method (n = 1). CONCLUSION This approach is technically feasible and makes transgastric NOTES cholecystectomy easier and safer.

Pancreatic duct holder for facilitating duct-to-mucosa pancreatojejunostomy after pancreatoduodenectomy

Duct-to-mucosa pancreatojejunostomy after pancreatoduodenectomy may be technically difficult, particularly in cases in which the remnant pancreas is soft with a small main pancreatic duct. We devised a pancreatic duct holder for duct-to-mucosa pancreatojejunostomy. The holder has a cone-shaped tip. A one-third circle of the tip is cut away, which makes a slit. As the tip is inserted gently into the pancreatic duct, the duct can be adequately expanded. The holder provides a good surgical field for anastomosis. A slit of the tip allows needle insertion. The holder facilitates stitches of the jejunum also. Twelve patients underwent pancreatoduodenectomy, followed by duct-to-mucosa pancreatojejunostomy using the holder. The holder allowed 8 or more stitches in duct-to-mucosa anastomosis, even in patients with a small pancreatic duct. No patients developed prolonged pancreatic leakage or pancreatic fistula postoperatively. In conclusion, the pancreatic duct holder is a simple and useful tool for facilitating duct-to-mucosa pancreatojejunostomy.