Takayuki Aimoto

Clinical outcome of laparoscopic distal pancreatectomy

BACKGROUND Few studies have compared laparoscopic distal pancreatectomy (Lap-DP) and open distal pancreatectomy (open-DP). The aim of this study was to evaluate the clinical outcome of Lap-DP and compare it to that of open-DP. METHODS A total of 37 patients who underwent distal pancreatectomy (Lap-DP, 21 patients; open-DP, 16 patients) between January 2000 and March 2007 were enrolled in this study. Prior to January 2004, open-DP was the standard procedure for patients with a lesion in the distal pancreas without invasive ductal cancer; thereafter, Lap-DP was also an approved procedure. All 16 open-DP procedures were performed prior to January 2004. RESULTS The operating times for the Lap-DP and open-DP patients were 308.4 +/- 124.6 and 281.5 +/- 83.3 min, respectively, and these were not significantly different (P = 0.4635). Blood loss for the Lap-DP group (249.0 +/- 239.8 ml) was significantly smaller than that for the open-DP group (714.1 +/- 650.4 ml) (P = 0.0055), and none of the patients in the Lap-DP group received transfusions. The frequency of complications for the Lap-DP and open-DP groups was 0 and 18.8%, respectively, which is not significantly different (P = 0.0784). The average hospital stay for the Lap-DP group was significantly shorter than that for the open-DP group (10.0 +/- 2.6 vs. 25.8 +/- 8.8 days; P < 0.0001). CONCLUSION In pancreatic diseases, other than invasive ductal cancer, arising in the distal pancreas, Lap-DP might be a more feasible and safer than open-DP.

Laparoscopic pancreatic resection: some benefits of evolving surgical techniques

Laparoscopic pancreatic resection began to be reported in the first half of the 1990s, with subsequent reports focusing primarily on the safety and usefulness of laparoscopic distal pancreatectomy (Lap-DP) for benign and low-malignancy lesions of the pancreatic body and tail (such as chronic pancreatitis, neuroendocrine tumor, mucinous cystic neoplasm, and intraductal papillary mucinous neoplasm). Recently we have also begun to see retrospective case-control studies comparing these techniques with open surgery, with Lap-DP showing advantages not only in terms of esthetics related to the surgical wound, but also with regard to reduced intraoperative bleeding, postoperative recovery time, and days of postoperative hospitalization. Prospective randomized controlled trials are still needed for confirmation, but it appears likely that this technique will become a standard surgical procedure for the treatment of diseases of the pancreatic body and tail. In contrast, laparoscopic pancreatoduodenectomy (Lap-PD) remains controversial in the minds of many pancreatic surgeons. This is primarily due to the difficulty of laparoscopic reconstruction following resection. However, there have recently been a number of single-center reports on the use of this procedure in at least 20 patients per center, showing that Lap-PD is associated with considerable reduction in intraoperative bleeding. Our own experience has been similar. In carefully selected patients, we find Lap-PD to be a useful surgical procedure.

Relationship Between Grade of Fibrosis in Pancreatic Stump and Postoperative Pancreatic Exocrine Activity After Pancreaticoduodenectomy

BACKGROUND Pancreaticoduodenectomy (PD) has become a standard operation for malignant and benign periampullary diseases. Although the operative mortality of PD has decreased to less than 4% in hospitals with many cases of PD, the leakage of pancreaticointestinal anastomosis (PIA) still carries a substantial risk of lethal outcome. The aim of this study was to evaluate the local factors that affect the incidence of PIA leakage by evaluation of exocrine function and fibrosis in the pancreatic remnant following PD. METHOD Twenty-eight patients (17 pancreatic disease, 8 bile duct cancers and 3 ampullary cancers) underwent PD with complete extracorporeal pancreatic juice drainage. The cut-end of the pancreatic remnant was histologically studied for its grade of fibrosis in comparison with the exocrine activity of the pancreatic remnant (EAPR) calculated by the value of the product of volume of drained pancreatic juice and its amylase activity. The influences of those factors and other clinicopathologic data on PIA outcome were evaluated. RESULTS The histological grade of fibrosis in the pancreatic stump was inversely correlated with EAPR (rs=0.5848, p=0.0011). Three patients had major leakages and 6 had minor leakages of PIA; all the patients with leakages had biliary or ampullary diseases, but not pancreatic diseases. The incidence of leakage of PIA was significantly higher in the patients with high values of EAPR (p<0.05). None with EAPR less than 10(7) had PIA leakage. The incidence of PIA leakage in low-grade fibrosis of the pancreatic stump was significantly higher than that in high-grade fibrosis (p<0.05). Other clinicopathologic data did not influence the incidence of leakage of PIA. CONCLUSIONS The degree of fibrosis in the pancreatic stump is significantly related to the EAPR and affects the development of PIA insufficiency as a local factor.

Clinicopathologic study on pancreatic groove carcinoma.

Objectives: Pancreatic groove carcinoma usually presents with duodenal stenosis. This report describes the clinicopathologic features of 5 cases. Methods: All the clinical and radiological features were reviewed retrospectively and analyzed to identify correlations with the histological findings. Results: Vomiting was an initial symptom in all cases, but obstructive jaundice was not inevitable until the disease progresses. Hypotonic duodenography demonstrated severe postbulbar stenosis. Pathological findings of biopsy specimens showed no evidence of malignancy at the early stage. Computed tomography revealed a hypovascular mass. Magnetic resonance imaging indicated a hypointense mass on T1-weighted images and an isointense to slightly hyperintense mass on T2 images. Macroscopically, the stenosis seemed to be the result of a hard yellowish-white tumor invading the duodenal wall. Histopathologically, an adenocarcinoma arising from the groove infiltrated the submucosal layer of the duodenum circumferentially. No cancer cells were found in the mucosa at the early stage. The intrapancreatic common bile duct was involved at the advanced stage. Conclusions: We believe that these features resulted from the anatomical characteristics of the groove involvement and that the string stricture of the duodenum resulted from invasion of the groove tumor into the submucosal layer around the wall.

The Controlled Release of Basic Fibroblast Growth Factor Promotes a Rapid Healing of Pancreaticojejunal Anastomosis with Potent Angiogenesis and Accelerates Apoptosis in Granulation Tissue

BACKGROUND Our previous study demonstrated that bFGF-GH promoted healing of the pancreaticojejunostomy (PJ) in an animal model. We examined the healing process in detail to investigate the significance of treatment with basic fibroblast growth factor (bFGF) incorporated in gelatin hydrogel (GH) microspheres for anastomotic healing. MATERIALS AND METHODS The optimal dose of bFGF was determined by administering bFGF concentrations of 1, 10, and 100 μg in six beagle dogs and assessing the results on d 7. Next, 28 dogs received a jejunal subserosal injection of 10 μg bFGF-GH or GH alone. The healing process was sequentially analyzed on d 4, 7, 21, and 28. The following types of assessment were performed: breaking strength test, pathologic examination, and calculations of collagen content, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) index, and microvessel density (MVD). RESULTS The administration of a bFGF dose of more than 10 μg induced a significantly higher breaking strength and more abundant granulation tissues. Histologic observations of the bFGF-GH group on d 7 and the GH-alone group on d 21 revealed abundant granulation tissue with migrating fibroblasts, inflammatory cells, and capillaries. Marked neovascularization and dense collagen deposition were detected in both groups on d 28. The collagen content and breaking strength did not significantly differ between both groups on d 28. A significantly higher TUNEL index and a rapid decline in the number of vimentin-positive cells were detected in the bFGF-GH group from d 21 onward. The MVD in the bFGF-GH group was significantly higher from d 7 onward CONCLUSIONS Basic FGF-GH administration can promote the rapid completion of PJ anastomosis and may help improve the quality of the healing of granulation tissue by conferring potent angiogenesis and accelerating apoptosis.

Multicentric pancreatic intraepithelial neoplasias (PanINs) presenting with the clinical features of chronic pancreatitis

A 46-year-old woman was readmitted to our hospital in August 2005 because of severe abdominal pain and nausea. Computed tomography demonstrated a huge cystic lesion in the retroperitoneal space behind the hepatoduodenal ligament and lesser peritoneal cavity. Endoscopic retrograde pancreatography revealed communication between the dilated main pancreatic duct and a pseudocyst. The condition was preoperatively diagnosed as chronic pancreatitis associated with a pseudocyst or an intraductal papillary mucinous neoplasm without mucin hypersecretion. The patient underwent a distal pancreatectomy with splenectomy. The pathologic diagnosis was multicentric pancreatic intraepithelial neoplasia (PanIN), and histological examination revealed a positive surgical margin around the remnant pancreas. Four months after the surgery, the patient underwent a total pancreatectomy. Macroscopic observation revealed diffuse fibrosis of the pancreatic parenchyma compatible with chronic pancreatitis. Histological examination revealed a constellation of noninvasive intraductal neoplasias with high-grade atypia, diffusely distributed in the small pancreatic ducts of the resected pancreas. Localized fibrosis and cystic dilation of the small ducts were detected in a lobule of exocrine glands draining into a ductule involved by PanIN lesions in the head of the pancreas. In summary, multicentric PanIN lesions are associated with lobular atrophy of the pancreatic parenchyma and chronic pancreatitis-like changes that follow. Total pancreatectomy may be recommended for patients with multicentric precursor lesions throughout the entire pancreas.

Leiomyosarcoma of the esophagus: Report of a case and preoperative evaluation by CT scan, endoscopie ultrasonography and angiography

SummaryA case of esophageal leiomyosarcoma, for which CT scan, endoscopie ultrasonography (EUS) and angiography were employed for preoperative diagnosis is reported. CT scan identified an exophytic mass which had no rim-enhancement in the lower end of the esophagus. EUS revealed a homogeneous mass originating from the muscularis propria. Angiography showed a mildly hypervascular tumor. Histologically, the resected specimen was a leiomyosarcoma. These results suggest that the evaluation by EUS combined with CT scan and angiography is useful in differentiating smooth muscle tumors from other submucosal tumors.

Improvement of Intraoperative Frozen Section Diagnosis in Patients with Biliary Strictures by Levovist Injection into the Bile Duct on Color Doppler Ultrasonography

BackgroundThis study evaluates the efficiency of color Doppler ultrasonography-guided intraoperative pancreatic biopsy (CDUS-IPB) using Levovist injected into the bile duct in conjunction with stimulated acoustic emission (SAE) in patients with biliary strictures.MethodsThe study was performed on 12 patients. After completing a conventional intraoperative pancreatic biopsy (c-IPB), each subject underwent CDUS with SAE imaging using Levovist. Upon identification of the biliary stricture, the IPB was taken from the area surrounding the stricture on the same imaging setting. Section diagnosis of the CDUS-IPB specimen was compared to that of the c-IPB specimen and resected tissue.ResultsBiliary strictures were identified as enhanced areas of color Doppler signal on CDUS. CDUS-IPB provided adequate specimens from the biliary strictures in all cases and corrected false-negative diagnoses by c-IPB in three cases. Section diagnosis by CDUS-IPB corresponded to the permanent section diagnosis. There were no complications.ConclusionsCDUS-IPB with Levovist is an accurate diagnostic tool. The method is especially useful for patients with a suspected malignant biliary stricture who show no tumor mass in preoperative images and no evidence of malignancy on cytologic examinations.

Features and choice of treatment of acute and chronic pancreatic pseudocysts--with special reference to invasive intervention.

Aims: It was the aim of this study to characterize the features of acute and chronic pancreatic pseudocysts (PPs) and to identify the factors predictive of the need for invasive treatment. Methods: Thirty-six patients with PPs treated at Nippon Medical School between January 1995 and December 2004 were studied retrospectively. The cases were divided into 4 groups based on 4 features: association with acute pancreatitis, association with chronic pancreatitis, spontaneous resolution, and persistent symptoms requiring therapeutic intervention. Group 1 included 9 patients with acute PPs which resolved spontaneously. Group 2 included 9 patients with acute PPs with persistent symptoms or associated complications requiring interventional treatment. Group 3 included 9 patients with chronic PPs which resolved spontaneously, and group 4 included 9 patients with chronic PPs with persistent symptoms or associated complications requiring interventional treatment. Results: Among the 36 patients, 13 were women and 23 were men. The etiologies were pancreatitis due to alcoholism in 18 cases (50.0%), biliary tract disease in 8 cases (22.2%) and other conditions in 10 cases (27.8%). The average duration of follow-up was 24.2 ± 18.5 months. The patients in group 1 were significantly older than those in group 2 (67.6 ± 16.1 vs. 40.6 ± 14.1 years; p = 0.011). The mean size of the PPs was significantly larger in groups 1 and 4 than in group 3 (p < 0.05) and significantly larger in group 2 than in group 4 (p < 0.05). There were no significant differences between groups 1 and 2 in the size of the PPs or in the Ranson score of previous pancreatitis. The increase in size of the PPs during follow-up in each of the spontaneously resolved groups (groups 1 and 3) differed significantly from that in each of the interventional treatment groups (groups 2 and 4; p < 0.05). The main cause of the acute pancreatitis in group 1 was biliary tract disease, while that in group 2 was alcoholism (significantly different, p < 0.05). The number of patients with symptoms related to pseudocysts at the time of diagnosis was significantly higher in group 1 than in group 3. Conclusions: Growth of the PPs during follow-up is the strongest predictor of the need for invasive treatment in both acute and chronic cases. Among acute PPs, the size of the pseudocyst is not in itself a predictor of invasive treatment. Invasive treatment may pose higher risks for pseudocysts with an etiology of alcoholic acute pancreatitis. However, the size of the pseudocyst may be a more important prognostic factor than an etiology of pancreatitis.

Usefulness of Color Coding Resected Samples from a Pancreaticoduodenectomy with Tissue Marking Dyes for a Detailed Examination of Surgical Margin Surrounding the Uncinate Process of the Pancreas

BACKGROUND Characteristics of a cancer-positive margin around a resected uncinate process of the pancreas (MUP) due to a pancreticoduodenectomy are difficult to understand by standardized evaluation because of its complex anatomy. The purposes of this study were to subclassify the MUP with tissue marking dyes of different colors and to identify the characteristics of sites that showed positivity for cancer cells in patients with pancreatic head carcinoma who underwent circumferential superior mesenteric arterial nerve plexus-preserving pancreaticoduodenectomy. Results of this evaluation were used to review operation procedures and perioperative methods. METHOD We divided the MUP into 4 sections and stained each section with a different color. These sections were the pancreatic head nerve plexus margin (Area A), portal vein groove margin (Area B), superior mesenteric artery margin (Area C), and left of the superior mesenteric artery margin (Area D). The subjects evaluated were 45 patients who had carcinoma of the pancreatic head and were treated with circumferential superior mesenteric arterial nerve plexus-preserving pancreaticoduodenectomy. RESULTS Of the 45 patients, nine cases (90%) of incomplete resection showed cancer-positivity in the MUP. Among the 4 sections of the MUP, the most cases of positive results [MUP (+) ] were found in Area B, with Area A (+), 0 case; Area B (+), 6 cases; Area C (+), 2 cases; and Area D (+), 3 cases (total, 11 sites in 9 patients). Relapse occurred in 7 of the 9 patients with MUP (+). Local recurrence was observed as initial relapse in all 3 patients with Area D (+). In contrast, the most common site of recurrence other than that in patients with Area D (+) was the liver. CONCLUSION By subclassifying the MUP with tissue marking dyes of different colors, we could confirm regional characteristics of MUP (+). As a result, circumferential superior mesenteric arterial nerve plexus-preserving pancreticoduodenectomy was able to be performed in R0 operations in selected patients while a better postoperative quality of life was maintained. Furthermore, Area D (+) represents an extension beyond the limit of the local disease and may indicate the need for early aggressive adjuvant chemotherapy.