Masaaki Tajima

Effect of Bevacizumab, a Humanized Monoclonal Antibody to Vascular Endothelial Growth Factor, on Peritoneal Metastasis of MNK-45P Human Gastric Cancer in Mice

BACKGROUND The aim of this study was to clarify the effect of bevacizumab on gastric cancer with peritoneal metastasis in nude mice. MATERIALS AND METHODS The expression of vascular endothelial growth factor mRNA (VEGF mRNA) in four gastric cancer cell lines, NCI-N87, MKN-45, MKN-45P, and Kato-III, was examined by polymerase chain reaction. We created a model of peritoneal metastasis by injecting mice with the human gastric cancer cell line MKN-45P. Mice were injected intraperitoneally with bevacizumab (0.1 mg/100 microL) on days 5-14, after inoculation (n = 10) or with phosphate-buffered saline (PBS) over the same time period (n = 10). The maximum abdominal circumference, ascites volume, and the total number and weight of peritoneal tumors were measured. To assess the effect of bevacizumab on angiogenesis, immunohistochemical analysis was performed. RESULTS VEGF mRNA was expressed at a high level in MKN-45P cells as well as MKN-45 and Kato-III. The mean maximum abdominal circumference and ascites volume in the bevacizumab group were significantly less than those in the control group (P < 0.001, respectively). The total weight of disseminated tumors in the bevacizumab group was also significantly less than that in the control group (P < 0.01). In addition, immunohistochemical analysis of CD31-stained peritoneally disseminated nodules showed that the vessel area in the bevacizumab group was significantly less than that in the control group (P < 0.001). CONCLUSIONS These results show that intraperitoneal administration of bevacizumab inhibits peritoneal metastasis and reduces malignant ascites in tumor-bearing mice.

Sodium alginate as an ideal submucosal injection material for endoscopic submucosal resection: preliminary experimental and clinical study.

BACKGROUND Sodium alginate is used clinically in the treatment of peptic ulcer disease. Because of its viscosity, sodium alginate could possibly become a new submucosal injection material for use in endoscopic resection. OBJECTIVE We evaluated the feasibility of endoscopic submucosal dissection (ESD) using sodium alginate. SETTING AND INTERVENTIONS The lesion-lifting properties of sodium alginate were examined in porcine stomachs and were compared with those of normal saline solution and sodium hyaluronate solution. After confirming the proper concentration of sodium alginate, ESD using sodium alginate was performed in 11 patients with gastric mucosal cancer or adenoma. MAIN OUTCOME MEASUREMENT The lesion-lifting properties of sodium alginate and clinical outcomes were assessed. RESULTS The thickness of the submucosal elevation created by 3% sodium alginate in porcine stomach was equivalent to that of sodium hyaluronate. ESD using sodium alginate was completed successfully in all patients without adverse effects except in 1 patient in whom transient shrinkage of the gastric wall disappeared spontaneously after approximately 30 minutes. The mean tumor size was 15.3 mm. En bloc resection and a negative resection margin were obtained in all. Histopathologic examination revealed that all tumors were confined to the mucosal layer except for 1 that was confined to the submucosal layer without lymphovascular invasion, and there were no adverse effects such as tissue damage. No patient required additional treatment, and none showed recurrence during a median follow-up period of 28 months. LIMITATIONS Small sample size. CONCLUSION This preliminary study suggests that sodium alginate might be a novel, safe submucosal injection material for use in endoscopic resection. Further investigation of the properties of sodium alginate is warranted.

Computed tomography of the gastrointestinal manifestation of hereditary angioedema

We report a case of gastrointestinal manifestation of hereditary angioedema. Computed tomography (CT) revealed wall thickening of the gastric antrum, duodenum, and jejunum. Dilatation of the third part of the duodenum, thickening of the small bowel mesentery and omentum, and retroperitoneal edema were present. The importance of considering this condition in patients presenting such CT findings correlated with the appropriate history is discussed.

Laparoscopic examination and resection for giant lipoma of the omentum: a case report and review of related literature.

We report herein the case of a giant lipoma of the greater omentum that was treated by laparoscopic surgery. A 71-year-old male patient was admitted with a diagnosis of sigmoid colon cancer. During preoperative examination, a gallbladder stone and an intra-abdominal giant lipoma were accidentally diagnosed. Laparoscopic examination revealed a smooth-surfaced, giant yellow tumor at the lower border of the greater omentum that was unattached to the surrounding organs. After laparoscopic resection of the tumor and cholecystectomy, a 10-cm midline incision was made in the lower abdomen to remove the tumor and the gallbladder. We then performed a sigmoidectomy for sigmoid colon cancer through the same laparotomy. The resected tumor measured 29×19×3 cm and weighed 1250 g, and a histopathologic examination revealed a benign lipoma. Laparoscopic examination and resection of a giant lipoma of the omentum are particularly useful.

Serosal and muscular layers incision technique in laparoscopic surgery for gastric gastrointestinal stromal tumors.

To minimize the resection of stomach tissue, especially for lesions close to the esophagogastric junction or pyloric ring, we developed laparoscopic wedge resection with the serosal and muscular layers incision technique (SAMIT) for gastric gastrointestinal stromal tumors.

Feasibility and functional efficacy of distal gastrectomy with jejunal interposition for gastric cancer: A case series

INTRODUCTION Distal gastrectomy with jejunal interposition (DGJI) has been used in our institution for selected patients with gastric cancer as a function-preserving gastrectomy. The aim of this retrospective study was to clarify the feasibility and functional efficacy of DGJI. METHODS A retrospective analysis was performed in 61 patients who underwent DGJI between 2002 and 2011. RESULTS Mean operation time was 393.8 min and blood loss was 463.3 ml. Postoperative early major complications developed in 2 (3.3%) patients. The most common complication was gastric stasis, occurring in 7 (11.5%) patients. All patients with complications recovered with conservative treatment, and no operative mortality occurred. Endoscopy 1 year after operation revealed reflux gastritis in 1 patient. Reflux esophagitis was not found in any patient. However, anastomotic ulcer was found in 12 (22.2%) patients over the 1-year period after operation. No patient reported symptoms of early and late dumping syndrome, and 1 (1.9%) patient self-reported diarrhea. CONCLUSIONS DGJI was a feasible and safe procedure with several advantages in terms of less incidence of reflux gastritis and esophagitis, dumping syndrome and diarrhea. However, this procedure is complicated and time-consuming, and it is necessary to be aware of the potential occurrence of an anastomotic ulcer at the site of the gastrojejunostomy after DGJI.