Atsuko Maruno

A case of successful placement of a fully covered metallic stent for hemobilia secondary to hepatocellular carcinoma with bile duct invasion.

Hemobilia represents gastrointestinal bleeding that develops as a result of communication between blood vessels and the biliary tract, which causes the blood to reach the duodenal papilla. It is characterized by biliary colic as the initial symptom, and the complications of cholangitis, obstructive jaundice and/or anemia. In general, definitive diagnosis is made by esophagogastroduodenoscopy which confirms bleeding from the duodenal papilla. Abdominal US and abdominal enhanced CT are performed to identify the source of the bleeding, as well as ERCP for biliary drainage to control the comorbid cholangitis. If active hemorrhage accompanied by worsening of the anemia is suspected, abdominal angiography is performed to selectively image the hepatic artery. Then, embolization of the culprit vessel is recommended. In our patients with difficult hemostasis, because of the direct compression hemostasis to the tumor site achieved with the fully covered metallic stent and secondary compression hemostasis due to blood clots, the bleeding could be controlled.

Risk Factors for Migration, Fracture, and Dislocation of Pancreatic Stents

Aim. To analyze the risk factors for pancreatic stent migration, dislocation, and fracture in chronic pancreatitis patients with pancreatic strictures. Materials and Methods. Endoscopic stent placements (total 386 times) were performed in 99 chronic pancreatitis patients with pancreatic duct stenosis at our institution between April 2006 and June 2014. We retrospectively examined the frequency of stent migration, dislocation, and fracture and analyzed the patient factors and stent factors. We also investigated the retrieval methods for migrated and fractured stents and their success rates. Results. The frequencies of stent migration, dislocation, and fracture were 1.5% (5/396), 0.8% (3/396), and 1.2% (4/396), respectively. No significant differences in the rates of migration, dislocation, or fracture were noted on the patient factors (etiology, cases undergoing endoscopic pancreatic sphincterotomy, location of pancreatic duct stenosis, existence of pancreatic stone, and approach from the main or minor papilla) and stent factors (duration of stent placement, numbers of stent placements, stent shape, diameter, and length). Stent retrieval was successful in all cases of migration. In cases of fractured stents, retrieval was successful in 2 of 4 cases. Conclusion. Stent migration, fracture, and dislocation are relatively rare, but possible complications. A good understanding of retrieval techniques is necessary.

Sex differences in immunohistochemical expression and capillary density in pancreatic solid pseudopapillary neoplasm.

Solid pseudopapillary neoplasm (SPN) is a rare and low-grade malignant pancreatic neoplasm. Solid pseudopapillary neoplasm is rare in men, and most SPN cases are in young women. This study aimed to investigate sex differences in SPN clinical histopathology including capillary density and expression of immunochemical markers, including glypican 3. A total of 22 resected tumors from pancreatic SPN patients, including 16 women (73%) and 6 men (27%), were analyzed histopathologically and immunohistochemically for synaptophysin, β-catenin, estrogen receptor, progesterone receptor, Ki-67, CD10, CD31, and glypican 3. The median age was 52.5 years in men and 24 years in women (P = .046). The median tumor size was 22.5 mm in men and 40 mm in women (P = .337). In 11 of the 16 women (69%), but in none of the men, tumors showed complete or incomplete fibrous cap`sules (P = .006). Cholesterol clefts were observed in tumors from 10 women (63%) but in none from the men (P = .012). No significant sex differences were noted in tumor characteristics, including size, macroscopic cystic degeneration, necrosis, lymphovascular involvement, and perineural invasion. The SPNs were weakly positive for glypican 3, although there was no significant difference between sexes. Capillary density tended to be lower in tumors from men than in those from women, but not significantly. Thus, except for the fibrous capsule and cholesterol clefts often found in tumors and the younger age of the women, there were no significant sex differences in histopathologic or immunohistochemical features of SPN, despite its markedly higher occurrence in women.

A Case of Pancreatic Intraepithelial Neoplasia That Was Difficult to Diagnose Preoperatively

A 63-year-old female patient presented to a local physician with pain in her back and epigastric region. An abdominal computed tomography (CT) scan revealed a pancreatic tumor, and the patient was referred to our hospital. Multiple imaging studies that included ultrasonography (US), CT, MRI, and endoscopic US revealed a cystic lesion 3-4 cm in size with node-like projections in the body of the pancreas. The distal main pancreatic duct was also found to be dilated. Endoscopic retrograde pancreatography revealed an irregular stenosis of the main pancreatic duct proximal to the cystic lesion, and malignancy was suspected. The patient was preoperatively diagnosed with pancreatic ductal carcinoma concomitant with intraductal papillary mucinous carcinoma, and a distal pancreatectomy was performed. Rapid pathological diagnosis during surgery revealed positive surgical margins for pancreatic intraepithelial neoplasia (PanIN). Further resection was performed twice, her surgical margin was positive and total pancreatectomy was ultimately conducted. Histopathological findings revealed diffuse microinvasive cancerous lesions corresponding to PanIN-2 (moderate dysplasia) to PanIN-3 (carcinoma in situ) throughout the pancreas. PanIN involves microlesions of the ductal epithelium that may precede pancreatic cancer. Ascertaining changes in PanIN using images provided by diagnostic modalities such as CT and US is challenging. Ductal stenosis and distal cystic lesions resulting from atrophy and fibrosis of pancreatic tissue were noted around PanIN. Considering the possibility of PanIN, a precancerous lesion during differential diagnosis will help to improve early detection and prognosis for patients with pancreatic cancer.

Risk factors for proximal migration of biliary tube stents.

AIM To analyze the risk factors for biliary stent migration in patients with benign and malignant strictures. METHODS Endoscopic stent placement was performed in 396 patients with bile duct stenosis, at our institution, between June 2003 and March 2009. The indications for bile duct stent implantation included common bile duct stone in 190 patients, malignant lesions in 112, chronic pancreatitis in 62, autoimmune pancreatitis in 14, trauma in eight, surgical complications in six, and primary sclerosing cholangitis (PSC) in four. We retrospectively examined the frequency of stent migration, and analyzed the patient factors (disease, whether endoscopic sphincterotomy was performed, location of bile duct stenosis and diameter of the bile duct) and stent characteristics (duration of stent placement, stent type, diameter and length). Moreover, we investigated retrieval methods for migrated stents and their associated success rates. RESULTS The frequency of tube stent migration in the total patient population was 3.5%. The cases in which tube stent migration occurred included those with common bile duct stones (3/190; 1.6%), malignant lesions (2/112; 1.8%), chronic pancreatitis (4/62; 6.5%), autoimmune pancreatitis (2/14; 14.3%), trauma (1/8; 12.5%), surgical complications (2/6; 33.3%), and PSC (0/4; 0%). The potential risk factors for migration included bile duct stenosis secondary to benign disease such as chronic pancreatitis and autoimmune pancreatitis (P = 0.030); stenosis of the lower bile duct (P = 0.031); bile duct diameter > 10 mm (P = 0.023); duration of stent placement > 1 mo (P = 0.007); use of straight-type stents (P < 0.001); and 10-Fr sized stents (P < 0.001). Retrieval of the migrated stents was successful in all cases. The grasping technique, using a basket or snare, was effective for pig-tailed or thin and straight stents, whereas the guidewire cannulation technique was effective for thick and straight stents. CONCLUSION Migration of tube stents within the bile duct is rare but possible, and it is important to determine the risk factors involved in stent migration.

Small serotonin-positive pancreatic endocrine tumors caused obstruction of the main pancreatic duct

We report 2 cases of pancreatic endocrine tumors that caused obstruction of the main pancreatic duct (MPD). A 49-year-old asymptomatic man was referred to our institution because dilation of the MPD was revealed by abdominal ultrasonography (US). No tumor was detected by endoscopic ultrasonography, computed tomography (CT), and magnetic resonance imaging (MRI). The diameter of the MPD was > 20 mm at the body, and no dilation was noted at the head. Although malignancy was not confirmed through cytology or imaging, pancreatic cancer was strongly suspected. Pancreaticoduo- denectomy was performed. Pathological and immunohistochemical examination revealed a 5 mm × 3 mm serotonin-positive endocrine tumor. Fibrosis was present around the MPD and seemed to cause stricture. A 32-year-old asymptomatic man had elevated serum amylase, and US demonstrated dilation of the MPD. No tumor was detected by CT and MRI. Pancreatic cancer was suspected due to stricture and dilation of the MPD. Pancreatectomy of middle part of pancreas was performed. Pathological and immunohistochemical examination revealed a serotonin-positive endocrine tumor sized 5 mm × 4 mm. We report 2 cases of serotonin-positive pancreatic endocrine tumors that caused stricture of the MPD in spite of the small size of the tumor.

Accessory Pancreatic Duct-Portal Vein Fistula: A Rare Complication of Chronic Pancreatitis during Endoscopic Retrograde Cholangiopancreatography.

Pancreatitis, hemorrhage and perforation are the most frequent complications associated with endoscopic retrograde cholangiopancreatography (ERCP). We report a rare case of accessory pancreatic duct-portal vein fistula, which occurred during ERCP in a patient with chronic pancreatitis. To our knowledge, this is the first report of accessory pancreatic duct-portal vein fistula created during ERCP by the use of a guide wire.

A Case of a Giant Growing Serous Cystic Neoplasm of the Pancreas

Because of the widespread use of diagnostic imaging in recent years, serous cystic neoplasm (SCN) of the pancreas can often be detected even when small in diameter. SCNs are usually benign, but it is important to differentiate them from other types of cystic tumors. We report a case of a giant growing SCN that posed a challenge in differential diagnosis.

Strategy of Endoscopic Pancreatic Duct Drainage for Recurrent Chronic Pancreatitis

Background: Methods of pancreatic duct (PD) drainage for recurrent chronic pancreatitis (CP) include endoscopic drainage combined with ESWL and surgical drainage. Although the endoscopic drainage has become widespread as this method is minimally invasive, there are cases in which stent removal is difficult. We retrospectively examined the current status of endoscopic drainage for recurrent CP at our hospital. Methods: This study included 66 patients with recurrent CP (57 men and 9 women with a mean age of 59 ± 14 years, including 58 patients with alcoholic CP) who underwent endoscopic drainage between April 2006 and April 2012. Based on the initial images of PD, the patients were classified into the following types to compare their backgrounds and treatment processes: pancreatolithiasis (Stone) type (7 patients), PD stenosis (Stenosis) type (18), and Stone+Stenosis type (41). Moreover, patients with PD stent were divided into the following groups to compare their backgrounds and treatment processes: stent-removed groupand stent-maintained group in which the stent could not be removed. Results: The procedure was successful in 61 patients (92%). Complete pain relief without analgesics was achieved in 60 patients (91%). The early complications were post-ERCP pancreatitis in 11 patients (2.7%, all mild in severity), and hemorrhage, basket impaction, and rupture of the pancreatic duct in 1 patient (0.5%) each. The late complications were pancreatic ductitis (0.7%), stent displacement (0.5%), stent migration (1.5%), and tear during removal of stent (1%). In Stone type patients, the mean number of procedural sessions and the number of patients who required at least 1 year of treatment were significantly smaller thanin those withPD stenosis (Stenosis type or Stone+Stenosis type) (P=0.0133 and P=0.0043, respectively). Patients with Stenosis type had a significantly smaller mean number of procedural sessions (P=0.0423) and a significantly lower incidence of complications (P=0.0366) than those with Stone+Stenosis type. Comparison between the stent-removed and stent-maintained groups revealed no significant differences in the mean number of procedural sessions, the number of patients with implantation of a stent with a diameter (thicker than 8.5-Fr), or the incidence of complications. In the stent-removed group, the number of patients who required at least 1 year of treatment was significantly smaller (P=0.0285). Conclusions: In the short term, endoscopic stenting combined with ESWL was effective for pain relief, was associated with a low incidence of complications, and could be performed safely and effectively. For Stonetype recurrent CP, endoscopic therapy is highly effective and useful. On the other hand, from the long-term perspective, there are cases, especially among those with the Stone+Stenosis type, in which stent removal is difficult. Thus, surgical drainage should also be considered.

An Intra-Abdominal Desmoid Tumor, Embedded in the Pancreas, Preoperatively Diagnosed as an Extragastric Growing Gastrointestinal Stromal Tumor

A 45-year-old woman was found to have a pancreatic tumor by abdominal ultrasound performed for a medical check-up. Abdominal contrast-enhanced computed tomography showed a hypovascular tumor measuring 30 mm in diameter in the pancreatic tail. Endoscopic ultrasound-guided fine needle aspiration was performed. An extragastric growing gastrointestinal stromal tumor was thereby diagnosed preoperatively, and surgical resection was planned. Laparoscopic surgery was attempted but conversion to open surgery was necessitated by extensive adhesions, and distal pancreatectomy, splenectomy, and partial gastrectomy were performed. The histological diagnosis was an intra-abdominal desmoid tumor. A desmoid tumor is a fibrous soft tissue tumor arising in the fascia and musculoaponeurotic tissues. It usually occurs in the extremities and abdominal wall, and only rarely in the abdominal cavity. We experienced a case with an intra-abdominal desmoid tumor that was histologically diagnosed after laparotomy, which had been preoperatively diagnosed as an extragastric growing gastrointestinal stromal tumor. Although rare, desmoid tumors should be considered in the differential diagnosis of intra-abdominal tumors. Herein, we report this case with a literature review.