Shinji Akita

Usefulness of transpapillary bile duct brushing cytology and forceps biopsy for improved diagnosis in patients with biliary strictures

Background and Aim:  Transpapillary bile duct brushing cytology and/or forceps biopsy was performed in the presence of an indwelling guidewire in patients with biliary stricture, and the treatment time, overall diagnosis rate, diagnosis rate of each disease, complications, and influences on subsequent biliary drainage were investigated.

Intracystic hemorrhage of a simple liver cyst mimicking a biliary cystadenocarcinoma

Simple liver cysts are rarely complicated by intracystic hemorrhage. We encountered a case of simple liver cyst that was morphologically similar to biliary cystadenocarcinoma, which was complicated by asymptomatic intracystic hemorrhage and successfully treated by right lobectomy. A large cystic lesion of the liver was detected in a 57-year-old woman during a mass screening health check. Abdominal ultrasonography (US) revealed that the cystic lesion, containing many hyperechoic papillary structures, occupied almost the entire region of the right hepatic lobe. In addition, a round mural nodule, measuring approximately 5 cm in diameter, was detected in the cystic wall. Abdominal computed tomography (CT) revealed that the inner part of the cystic lesion showed homogeneous low density, but CT did not show the round nodule detected by US. On T1-weighted sequence of magnetic resonance imaging (MRI), the lesion showed homogeneous high signals, together with a low-signal tumorous lesion in the cystic wall. T2-weighted sequence of MRI showed unhomogeneous high signals, together with high signals in the tumorous part. These findings did not exclude the possibility of a malignant cystic tumor, such as biliary cystadenocarcinoma. Therefore, right lobectomy was performed. Histological examinations of resected tissue specimens revealed that the lesion was a liver cyst containing a large amount of blood clot, and that the tumorous lesion detected by US and MRI was a large mass of blood clot which was partly liquefied. This case indicates the diagnostic importance of the morphological discordance between CT and US or MRI findings for liver cyst containing a large amount of blood clot.

Intrahepatic biliary papilloma morphologically similar to biliary cystadenoma

Abstract  A 37‐year‐old man presented complaining of epigastralgia. Abdominal ultrasonography revealed the presence of a papillary tumor (9 mm in diameter) in the cystic lesion (18 mm in diameter) in hepatic segment 4, which was accompanied by mild intrahepatic bile duct dilatation. Although abdominal computed tomography also showed the cystic lesion, it did not show papillary tumors inside the lesion. Endoscopic retrograde cholangiography showed the communication between the cystic lesion and the left hepatic duct. In addition, mucus was observed in the common bile duct. When transpapillary intraductal ultrasonography was performed through the left hepatic duct using a fine ultrasonic probe, a hyperechoic papillary and lobulated tumor was clearly shown in the cystic lesion. The wall of the cyst was smooth and there was no sign of tumor infiltration. Based on these findings, biliary cystadenoma was diagnosed and an extended left lobectomy was carried out. However, pathological findings postoperatively revealed that the lesion was a localized biliary papilloma, developing and extending to the intrahepatic duct. This case is rare and there have been no published reports describing a biliary papilloma morphologically similar to biliary cystadenoma.

Exophytic pedunculated gastrointestinal stromal tumor with remarkable cystic change

A 59-year-old man with bloody stools, and previously diagnosed with sigmoid colon carcinoma, visited our hospital. Preoperative abdominal ultrasonography (US) showed another tumor, with an uneven irregular surface, measuring about 9 × 5 cm, below the left hypochondrium. The tumor consisted of several cysts. Abdominal computed tomography (CT) showed a multicystic tumor attached to the stomach, and its septum and marginal region were intensely stained on contrast imaging. On magnetic resonance imaging (MRI), low and markedly high signals were revealed in the tumor on T1-weighted and T2-weighted sequences, respectively. Contrast imaging of the upper digestive tract showed extramural compression of the greater curvature of the antral stomach by the tumor. The tumor was partially imaged by endoscopic ultrasonography (EUS), but continuity to the stomach was not confirmed. On abdominal angiography, the tumor was slightly stained via the gastroepiploic arteries. Surgical treatment was performed to excise both the gastric tumor and the sigmoid colon carcinoma. The gastric tumor was removed with gastric wall tissue where the tumor was attached to a 2-cm pedicle. It was multicystic, contained watery fluid, and had a smooth outer surface. Histologically, the tumor consisted of multiple irregular cysts without epithelial lining, and solid epitheloid cell nests in between. The tumor cells had clear or eosinophilic cytoplasm and round nuclei. No mitotic figures were seen. The tumor cells in the pedicle were connected with the muscularis propriae of the stomach. Immunohistochemistry showed c-kit-positive, CD34-positive smooth muscle actin (SMA)-negative, and S-100-negative staining of tumor cells. The final diagnosis was gastrointestinal stromal tumor (GIST).

Rupture of hepatic aneurysm complicating hereditary hemorrhagic telangiectasia (Osler-Weber-Rendu disease) for which hepatic arterial coil embolization was effective.

A 74‐year‐old woman was transferred to our hospital for further examinations because of abdominal fullness and abnormal levels of serum liver/biliary enzyme persisting for 3 weeks. She had anemia and dilatation of many capillary vessels in her fingers, palms, and tongue in addition to reporting frequent incidences of nasal bleeding in herself and her family. Abdominal ultrasonography detected a cystic lesion in the right hepatic lobe, connected to a dilated tortuous hepatic artery. A low‐echoic hepatic phyma was also detected in the back of the cystic lesion. Abdominal computed tomography and magnetic resonance imaging indicated that the cystic lesion was an aneurysm and the low‐echoic phyma was a hematoma. Hepatic arteriography confirmed a hepatic aneurysm, tortuous dilatation of the hepatic artery, and the complication of an arteriovenous shunt in the liver. Taking all of these findings into consideration, this case was diagnosed as hereditary hemorrhagic telangiectasia (HTT) complicated by a hepatic aneurysm causing intrahepatic hematoma. To prevent re‐rupture of the aneurysm, we performed a hepatic arterial coil embolization. After therapy, no blood flow to the aneurysm was detected by ultrasonic color Doppler method and the hematoma gradually diminished. There have been no reports of a case in which hepatic arterial embolization was effective for HHT‐associated hepatic aneurysm causing intrahepatic hematoma. This very rare case provides important clinical information regarding abdominal vascular complications of HTT and a less invasive treatment for them.

Acid stimulates E-cadherin surface expression on gastric epithelial cells to stabilize barrier functions via influx of calcium

Background and aims E-cadherin, which is a [Ca21]-dependent, homotypic cell–cell adhesion molecule, is expressed in gastrointestinal epithelial cells. Much has been learned about the down-regulation of E-cadherin expression in gastrointestinal tumours, Barretts oesophageal dysplasia, and Crohns disease, but the functions of this molecule in normal gastrointestinal mucosa are less known. Methods In this study, we investigated the relationship between E-cadherin expression and permeability using rat cultured gastric and intestinal epithelial cells following a 30-min exposure to various pH solutions. We also investigated the participation of [Ca21] in these events. Results E-cadherin expression increased under acid (pH 4) but not alkali (pH 10 or 11) exposure only for gastric epithelial cells. Gastric epithelial permeability was maintained only against acid exposure while intestinal permeability increased under both conditions. Transient influx of [Ca21] was only observed for gastric epithelial cells just after acid exposure. Conclusions These findings suggest that E-cadherin expression on gastric epithelium stabilizes the epithelial barrier against acid, probably through influx of [Ca21]. This event is thought to be one of the protective mechanisms in gastric mucosa against acid back-diffusion, which is one of the causes of peptic ulcer formation.

Clinical evaluation of double stenting for duodenal and biliary obstructions caused by pancreatic head carcinoma using covered self‐expandable metallic stents

Five patients with non‐resectable pancreatic head carcinoma complicated by duodenal and biliary obstructions were successfully treated by double stenting with covered self‐expandable metallic stents (EMS). Diamond (Boston Scientific, Natick City, MA, USA) stents covered with a polyurethane membrane were used to treat biliary obstructions, whereas covered Ultraflex (Boston Scientific) stents for esophageal stenting were used to treat duodenal obstructions. That is, Diamond stents were initially placed in the biliary tract percutaneously in one patient and endoscopically in the remaining four patients. Subsequently, covered Ultraflex stents were placed in the duodenum. Double stenting with EMS was successfully performed in all five patients without inducing early technical complications. All patients were able to take a liquid diet orally at a mean 1.6 days after the double stenting procedure and were able to eat solid foods thereafter. Sludge‐induced biliary obstructions were detected in two patients 3 and 6 months after the placement of EMS. However, recurrent biliary obstruction was not noted in the remaining three patients. The EMS left in the duodenum were not obstructed during the observation period. The survival period of the patients ranged from 86 to 363 days (mean 172 days). There have not been any reports evaluating the usefulness of double stenting using covered EMS for duodenal and biliary obstructions. Because favorable results were obtained by double stenting in our patients, stenting for duodenal and biliary obstructions caused by non‐resectable pancreatic head carcinoma may become a useful treatment modality substituting for bypass surgery.

Clinical evaluation of the Haber RAMPTM catheter for endoscopic bilateral metal stent placement in patients with malignant hilar strictures

Background:  Endoscopic bilateral expandable metal stent (EMS) placement has been performed in malignant hilar strictures. To perform EMS placement successfully, insertion of guidewires into the bilateral intrahepatic bile ducts is an important and necessary step. In the present study, we evaluated the usefulness of the Haber RAMPTM catheter (HRC) for the selective insertion of guidewires.

Gastric vascular ectasia treated by endoscopic mucosal resection

An 80‐year‐old woman consulted our hospital complaining of general weakness. She had iron deficiency anemia, and upper gastrointestinal endoscopy revealed a small lesion accompanying a small amount of fresh bleeding in the stomach. Close observation of the lesion revealed that it was composed of a local assembly of dilated microvessels. The diagnosis of this patient was gastric vascular ectasia causing anemia. Endoscopic ultrasonography demonstrated that the lesion involved the mucosal and submucosal layers of the stomach, and that there were no large vessels inflowing to or outflowing from the lesion. In the present case, we attempted endoscopic mucosal resection (EMR). The lesion was completely resected by only one procedure of EMR without complications such as bleeding. After the endoscopic treatment, iron deficiency anemia improved. Follow‐up endoscopy performed 1 year later revealed that there was no residual or recurrent lesion. Although there have not been any published reports describing the use of EMR for gastric vascular ectasia, EMR may be a useful endoscopic treatment for this condition.

Usefulness of the Memory® 8‐wire basket forceps for endoscopic extraction of common bile duct stones after endoscopic sphincterotomy

Background:  The present study was performed to evaluate the usefulness of the Memory® 8‐wire basket forceps for extracting small common bile duct stones after endoscopic sphincterotomy (EST).