Yorihiko Muto

Salivary amylase activity is useful for assessing perioperative stress in response to pain in patients undergoing endoscopic submucosal dissection of gastric tumors under deep sedation

BackgroundAlthough endoscopic submucosal dissection (ESD) for patients with gastric tumors under the conditions of unconsciousness is considered to be minimally invasive, no objective assessment of the perioperative stress of ESD has yet been conducted. Today, stress levels can be easily and objectively assessed by monitoring salivary amylase activity (sAMY). We evaluated the perioperative changes in the sAMY in patients undergoing ESD and identified the causes of such changes.MethodsA total of 40 patients with gastric cancers/adenomas removed by ESD under general anesthesia (GA; n = 20) and under deep sedation (DS; n = 20) were enrolled. sAMY was measured using the enzyme analysis equipment, sAMY Monitor (NIPRO, Osaka, Japan) during the perioperative period of the ESD. Also, all patients were interviewed to determine their subjective stress level, using a questionnaire asking “How did you feel during ESD?”, with the choice of responses ranging from “did not wake up at all” to “I was awake and ESD was extremely stressful”.ResultsThe sAMY of the DS group increased soon after the start of ESD. Meanwhile, that of the GA group decreased just after the ESD started and was maintained at a stable level throughout the ESD. In response to the stress level questionnaire, all of the patients in the GA group and a majority of the patients in the DS group responded, “did not wake up at all”.ConclusionSympathetic agitation, expressed as an increase of sAMY, was absent in the GA group. Meanwhile, in the DS group, some patients showed high levels of sAMY which went down following the administration of an analgesic agent, thus suggesting that pain caused an elevation in the level of the stress and thereby induced an increase in sAMY. The measurement of sAMY is therefore considered to be useful for the assessment of analgesic status under DS.

Performing simple and safe dunking pancreaticojejunostomy using mattress sutures in pure laparoscopic pancreaticoduodenectomy.

BackgroundAlthough recent technological developments and improved endoscopic procedures have further spread the application of laparoscopic pancreatic resection, laparoscopic pancreaticoduodenectomy still presents major technical difficulties, such as when performing pancreatic–enteric anastomosis.MethodsLaparoscopic dunking pancreaticojejunostomy using mattress sutures was performed in 15 consecutive patients with a soft pancreas and a nondilated pancreatic duct between October 2011 and December 2012.ResultsAccording to the International Study Group on Pancreatic Fistula criteria, 3 patients developed PF (grade A), whereas the remaining 12 patients did not.ConclusionsDunking pancreaticojejunostomy using mattress sutures is considered to be a feasible and safe method for performing pure laparoscopic pancreaticoduodenectomy.

Rapid diagnosis of micrometastasis of gastric cancer using reverse transcription loop-mediated isothermal amplification

Methods to detect metastases in biopsy specimens with certain rapidity and accuracy are essential to performing tailor-made surgeries for solid malignancies. Reverse transcription loop-mediated isothermal amplification (RT-LAMP) reaction is a novel technique for detecting mRNA expression of target sequences with high sensitivity and rapidity, even from crude samples without RNA purification. Applicability to detect lymph node (LN) micrometastasis of gastric cancer was tested. Total of 26 LNs were retrieved from 10 patients with primary gastric cancer. Each LN was serially sectioned, and every set of three serial sections were tested for routine histopathological (H&E) and immunohistochemical examination with anti-cytokeratin antibodies (IHC), and RT-LAMP analysis targeted cytokeratin 19 mRNA. Results from H&E/IHC and RT-LAMP analysis were compared in each set of sections. All the sections of those containing metastatic lesions equivalent to a volume of overt metastasis (maximum diameter>2 mm), 90% of those containing micrometastasis (between 2 and 0.2 mm) and 83% of those containing isolated tumor cells (<0.2 mm) were detectable using this procedure. Total analysis from lysates of clinical specimens required<75 min. This new technique is suggested to be an alternative to rapid diagnosis of micrometastasis based on conventional histopathological analysis.

Endoscopic occlusion with silicone spigots for the closure of refractory esophago-bronchiole fistula after esophagectomy

A 65-year-old man with cT1bN0M0 stage I middle thoracic esophageal cancer underwent subtotal esophagectomy and gastric tube reconstruction through the posterior mediastinal route after preoperative carbon-ion radiotherapy and chemotherapy in a clinical trial. Anastomotic leakage occurred, but it spontaneously improved. At six months after the operation, he was rehospitalized with a cough and dysphagia. An esophago-bronchiole fistula and stenosis of the gastric tube were observed. He first underwent stent placement in the gastric tube. Two weeks later, the syringeal epithelium was burned by argon plasma coagulation after stent removal. Endoscopic occlusion was then performed for the fistula with two guidewire-assisted silicone spigots. Two weeks later, he was discharged on an oral diet, and he has not developed recurrence of the fistula or cancer for three years. This is the first report of endoscopic occlusion with a guidewire-assisted silicone spigot through the esophagus.

Comparison of Efficacy of Self-Expandable Metallic Stent Placement in the Unresectable Esophageal Cancer Patients

This is a retrospective study to evaluate the prevention of complications of metallic stent placement in patients with unresectable advanced esophageal cancer. A total of 87 patients were treated with 4 types of metal stents in the esophagus over a period of 18 years. Stent placement was technically successful. The most common prior treatment was chemoradiotherapy. There were no significant differences in the rate of patients with no complications among the prior treatments. Approximately, 30% of patients had the most common chest pain in complications. Stent placement within one month after the completion of chemoradiotherapy should be avoided for the prevention of the chest pain. There was no significant difference in the rate of patients with no complications by lesion location. The rate of no complications was higher for the Niti-S stent than the Gianturco Z-stent or Ultraflex stent. Of note, no complications were noted for the Niti-S ultrathin stent at all. Among cases of stent-related death, the most common type of complication was respiratory disorder caused by the stent that seems to be thick and hard. Therefore, the stent with thin and flexible characteristics like the Niti-S ultrathin stent will solve the various problems of esophageal stent placement.