Masanobu Mori

An assessment of the feasibility of sentinel lymph node-guided surgery for gastric cancer

BackgroundSentinel node-guided surgery has received increasing attention in tumor surgery. To ascertain whether sentinel lymph node (SLN)-guided surgery is feasible for gastric cancers 4 cm or less in size, we conducted a multicenter clinical study.MethodsOne milliliter of isosulfan blue was injected endoscopically into the gastric wall at four sites around a gastric cancer lesion. Approximately 15 min after the injection of the dye, the surgeons resected (picked-up) the stained blue nodes (defined as SLNs) around the stomach.ResultsSLNs were detected in 140 of 144 patients (97.2%). The average number of SLNs was 3.3. In 99 patients with D2 lymph node dissection, the false-negative rate (FNR) was evaluated. In 14 T1 patients with pathological positive lymph node metastasis (pN(+)), the FNR was 29%. In 9 T2,3 pN(+) patients, the FNR was 44%. In T1 patients with pN(+) but macroscopically normal lymph nodes during surgery (sN0), the FNR was 11% (1/9).ConclusionT1 and sN0 patients may be a target group for the study of SLN-guided surgery. A larger multicenter trial should be performed to clarify the application of sentinel node navigation surgery for gastric cancer.

Nitric oxide mediates cerulein-induced relaxation of canine sphincter of Oddi.

This study evaluates the hypothesis thatcerulein relaxes the sphincter of Oddi (SO) via nitricoxide (NO). The spontaneous motility and the response tocerulein on the canine SO were recorded using aconstant-perfusion technique.NG-L-arginine-methyl-ester (L-NAME) increasedthe spontaneous motility and dose-dependently reducedthe cerulein-induced inhibitory response of the SO.After treatment with L-NAME at higher doses, cerulein induced an excitatory response.This effect was reversed by treatment with excessL-arginine. Similar results were obtained usingcholecystokinin octapeptide in place of cerulein. Inseparate studies, cerulein generated increases inintracellular cAMP and cGMP levels in the SO. Thisindicates that the intracellular mechanism mediatingcerulein-induced relaxation involves the production ofcAMP and cGMP. On the other hand, treatment withL-NAME absorbed the increase in cAMP and cGMP levels bycerulein. These studies demonstrate that ceruleinrelaxes the canine SO mainly via NO, increasingintracellular cAMP and cGMP levels.

Continuous Monitoring of Nitric Oxide Release Induced by Cholecystokinin from the Choledochal Sphincter in Guinea Pigs

Background/Aims: Many in vitro studies in the choledochoduodenal junction of the guinea pig have shown that cholecystokinin (CCK) contracts the sphincter of Oddi (SO). This study, using the choledochal sphincter of the guinea pig as the SO, evaluates the hypothesis that effects of CCK on the SO were mediated by nitric oxide (NO). Methods: Spontaneous motility and effects of CCK on the choledochal sphincter were recorded using a constant-perfusion technique, and direct measurement of NO release using a specific NO sensor was performed at the same time. Results: CCK-8 decreased the phasic wave amplitude of the choledochal sphincter, and increased NO release. NG-L-arginine-methyl-ester (L-NAME), an inhibitor of NO synthase, increased the spontaneous motility and converted the CCK-induced inhibitory response into an excitatory response. L-NAME also reduced NO release and abolished the increase of NO that had been caused by CCK-8. These effects were reduced by treatment with L-arginine (L-Arg). L-Arg application enhanced NO release, and recovered the increase of NO by CCK-8. Conclusion: These studies demonstrate that CCK relaxes the choledochal sphincter and this relaxant response is mediated by NO.

Solitary splenic metastasis of pulmonary carcinoid: A rare case report and literature review

We herein report a rare case of solitary splenic metastasis of a pulmonary carcinoid, for which hand-assisted laparoscopic splenectomy was performed. A 73-year-old man was admitted to the Inoue Hospital (Fukuyama, Japan) in March 2015 with an abnormal shadow of the spleen. The patient had a history of right upper lobectomy with lymph node dissection for a pulmonary typical carcinoid (pT1N0M0 stage IA) 7 years earlier. Plain abdominal computed tomography (CT) revealed a low-density area in the spleen. Enhanced abdominal CT revealed a mass in the spleen measuring 3×3 cm. Blood tests and tumor marker analysis revealed no abnormalities. Abdominal magnetic resonance imaging revealed a mass that was low-intensity on T1- and high-intensity on T2-weighted images, and positron emission tomography revealed abnormal fluorodeoxyglucose accumulation in the mass. Hand-assisted laparoscopic splenectomy was performed for diagnosis and treatment. The resected specimen included a reddish-brown mass. On immunohistochemistry, the mass was positive for chromogranin A, synaptophysin and CD56, which was similar to the resected pulmonary carcinoid tumor; thus, splenic metastasis of pulmonary carcinoid was diagnosed. The postoperative course was uneventful and the patient is currently under observation and remains recurrence-free, with no adjuvant chemotherapy.

The Long-Term Survival of Patients with Ductal Carcinoma of the Pancreatic Head and Body

Seventy-six patients with ductal carcinoma of the pancreatic head and body who underwent resection during the past 20 years were studied. Included were 1 patient in stage I, 5 patients in stage II, 27 patients in stage III, 24 patients in stage IVa, and 19 patients in stage IVb. Curative resection was achieved in 100% of the patients with stage I and II, 81.5% of stage III, 41.7% of stage IVa, and 10.5% of stage IVb. The surgical procedure involved pancreatoduodenectomy or total pancreatectomy with extensive skeletonization. Intraoperative radiotherapy and perioperative chemotherapy were seldom performed. Surgical mortality (deaths within 3 months after surgery) decreased from 19.4% before 1986 to 2.5% after 1987. There were 11 (18.6%) long-term survivors of more than 3 years among 59 patients and 7 (15.2%) survivors of more than 5 years among 46 patients. These long-term survivors were all found in the group that underwent pathologically curative resection, and there were no long-term survivors among patients with pathologically noncurative resection. In the group receiving curative resection, 28.9% (11/38) of patients survived more than 3 years and 24.1% (7/29) of patients survived more than 5 years. The 3-year-survival rates were 60% in stages I and II, 26.9% in stage III, 4.2% in stage IVa, and none in stage IVb; the 5-year-survival rates were 40% in stages I and II, 19.2% in stage III, and none in stage IV. Curative resection should be applied to patients with stages I, II, III, and IVa tumors, and excessive surgery should be avoided for patients with stage IVb.