Can mechanical balloon dissection be applied to cleave fibrotic submucosal tissues? A pilot study in a porcine model.

BACKGROUND AND STUDY AIMS: Removal of a lesion containing an ulcer scar is one of the most challenging applications of endoscopic submucosal dissection (ESD). The present study examined whether a novel balloon dissector could cleave fibrotic submucosal tissue beneath ulcer scars. METHODS: Six pigs were studied. Endoscopic mucosal resection (EMR) with ligation was performed at 7 or 8 sites in the stomach for each animal; 4 weeks later, 23 sites with a visible scar were selected for submucosal dissection. The procedure involved first creating a submucosal fluid cushion (SFC) by injecting either saline mixed with mesna or pure saline. A slender, compliant balloon with a diameter of 8, 13, or 18 mm was inserted into the SFC. The balloon was unfolded and thrust forward to cleave the fibrotic submucosa over approximately 5 cm. RESULTS: Fibrotic submucosa was dissected within 90 seconds in 17 of 23 attempts. Isolating the ulcer scar from the muscularis with the SFC prior to balloon dissection and using a thinner balloon catheter both ensured a better dissection. CONCLUSIONS: The fibrotic submucosa underlying post-EMR scars can be dissected with the novel balloon dissector, although the technique is less effective in cases with no sign of lifting.

Initial evaluation of a novel multibending backward-oblique viewing duodenoscope in endoscopic retrograde cholangiopancreatography.

A novel multibending backward-oblique viewing duodenoscope was developed to overcome the difficult technical aspect of deep cannulation into the bile duct during endoscopic retrograde cholangiopancreatography (ERCP). The aim of the present study was to evaluate the initial experience of a novel multibending backward-oblique viewing duodenoscope (M-D scope) for ERCP. This was a retrospective review of 23 patients with native papilla who received biliary ERCP with the M-D scope between April and December 2010. The procedures were performed by two well-experienced endoscopists. In all patients, biliary cannulation and therapeutic procedure were successfully completed. In two patients with Billroth I gastrectomy, ERCP were initially attempted with a conventional single-bending duodenoscope, but biliary cannulations were unsuccessful. However, with the use of the M-D scope, biliary cannulation and therapeutic procedures were successfully completed. A novel multibending backward-oblique viewing duodenoscope is safe and feasible for therapeutic and diagnostic ERCP.

Chemically assisted submucosal injection facilitates endoscopic submucosal dissection of gastric neoplasms.

BACKGROUND AND STUDY AIMS: A randomized in vivo animal study previously demonstrated that topical injection of mesna solution (sodium-2-mercaptoethanesulfonate) chemically softened submucosal connective tissues and facilitated mechanical dissection of the submucosal tissue plane. The present study evaluated the technical feasibility and safety of chemically assisted endoscopic submucosal dissection (CA-ESD) using mesna in 20 consecutive patients who underwent endoscopic excision of gastric neoplasm. MATERIALS AND METHODS: Following the margination of the lesion with a mucosal circumcision, 4 - 12 mL of 10 % mesna solution was injected into the submucosal layer. Mechanical submucosal dissection was then performed by bluntly cleaving the chemically treated submucosal layer with the tip of a cap-fitted gastroscope. The use of cautery was restricted to prophylactic hemostasis, dissection of the coagulated vessels and persistent submucosal tissues, and the final snare resection. Post-therapeutic ulceration repair and adverse events were followed up during a 1-week hospitalization and by repeat endoscopies at 1 day, 1 week, and 1 month after the procedure. RESULTS: Sixteen gastric cancers and four adenomas were treated in this study. The sampled tissue measured 38.25 +/- 14.53 mm, with an en bloc resection rate of 100 %. Mean operation time was 21.17 +/- 11.6 minutes. The time spent using cautery was limited to 26.1 % of the total submucosal dissection time. Ulcerations healed normally without complications. CONCLUSIONS: This preliminary study demonstrates that submucosal injection of mesna facilitates and expedites mechanical submucosal dissection. The major limitations in this study include the single-arm study design and a small patient population.

Endoscopic ultrasound-guided drainage of abdominal abscesses and infected necrosis.

Traditionally abdominal abscesses have been treated with either surgical or radiologically guided percutaneous drainage. Surgical drainage procedures may be associated with considerable morbidity and mortality, and serious complications may also arise from percutaneous drainage. Endoscopic ultrasound (EUS)-guided drainage of well-demarcated abdominal abscesses, with adjunctive endoscopic debridement in the presence of solid necrotic debris, has been shown to be feasible and safe. This multicenter review summarizes the current status of the EUS-guided approach, describes the available and emerging techniques, and highlights the indications, limitations, and safety issues.

Magnifying endoscopy combined with narrow-band imaging for differential diagnosis of superficial depressed gastric lesions.

BACKGROUND AND AIM: Magnifying endoscopy combined with narrow-band imaging (ME-NBI) has been used for differential diagnosis of various focal lesions. The aim of our study was to evaluate ME-NBI criteria for cancer diagnosis in superficial depressed gastric lesions in comparison to conventional white light endoscopy (WLE). PATIENTS AND METHODS: ME-NBI and WLE images of 100 superficial gastric depressions (55 depressed cancers, 45 benign depressions) were independently evaluated by 11 endoscopists blinded to the diagnosis in each case. The presence or absence of predefined ME-NBI findings relating to microvasculature and fine mucosal structure (FMS) was recorded. A general diagnosis of benign or malignant also had to be given on the basis of a general assessment of features of color and shape as shown in the ME-NBI and WLE images, respectively, without regard to any prespecified criteria. RESULTS: Multivariate and ROC analysis demonstrated that the triad of FMS disappearance, microvascular dilation, and heterogeneity appeared to be the best combination for diagnosis of gastric cancer. ME-NBI diagnosis with the triad attained a good specificity (85 %, theoretically calculated if all of the triad were positive), which was significantly ( P < 0.001) superior to WLE general diagnosis (65 %), and comparable with ME-NBI general diagnosis (80 %). The sensitivities of the three diagnoses (ME-NBI with the triad 69 %, WLE general diagnosis 71 %, ME-NBI general diagnosis 72 %) were comparably moderate. The kappa values (interobserver concordance) for ME-NBI diagnosis with the triad (0.47) and ME-NBI general diagnosis (0.48) were superior to the kappa value for WLE diagnosis (0.34). CONCLUSION: The triad of FMS disappearance, microvascular dilation, and heterogeneity has good specificity for the diagnosis of superficial depressed gastric carcinoma, but the sensitivity needs to be improved.

A pilot study of EUS-guided hot saline injection for induction of pancreatic tissue necrosis.

BACKGROUND AND STUDY AIMS: Hot saline may be potentially useful for inducing necrosis of pancreatic tissue. However, the local and systemic effects are largely unknown. This pilot study aimed to evaluate the feasibility and safety of EUS-guided injection of hot saline into the pancreas in the porcine model. METHODS: Boiling hot saline was injected into the tail of normal porcine pancreas under EUS guidance in six pigs via a transgastric approach. Three pigs were killed 4 hours later to study the acute effect of the hot saline injection (acute study). The remaining three pigs were killed after 7 days of clinical observation (survival study). RESULT: Injection of 5 mL, 2 mL and 1 mL of hot saline produced localized necrosis (7 - 10 mm) of pancreatic tissue in the acute study. However, there was pooling of hot saline on the surface of the pancreas when 5mL was injected. On the basis of the results of the acute study, the volume of hot saline injected in the survival study was 1 mL. One milliliter of hot saline produced localized or sporadic necrosis of pancreatic tissue without any signs of pancreatitis in all three pigs in the survival study; hot saline was observed to pool on the pancreatic surface of one pig. There was no histological evidence of necrosis in the pancreatic tissue adjacent to the pooled hot saline in either the acute or the survival study. CONCLUSION: EUS-guided hot saline injection of pancreatic tissue in the porcine model was technically successful and led to localized necrosis of pancreatic tissue without any sign of pancreatitis.

Magnifying endoscopy with narrow band imaging for predicting the invasion depth of superficial esophageal squamous cell carcinoma.

The invasion depth of superficial esophageal squamous cell carcinoma is important in determining therapeutic strategy. The aim of this study was to prospectively investigate the clinical utility of magnifying endoscopy with narrow band imaging compared with that of non-magnifying high-resolution endoscopy or high-frequency endoscopic ultrasonography in predicting the depth of superficial esophageal squamous cell carcinoma. The techniques were carried out in 72 patients with 101 superficial esophageal squamous cell carcinomas, which were then resected by either endoscopic mucosal resection or esophagectomy. The histological invasion depth was divided into two: mucosal or submucosal carcinoma. We investigated the relationship between endoscopic staging and histology of tumor depth. Non-magnifying high-resolution endoscopy, magnifying endoscopy with narrow band imaging, and high-frequency endoscopic ultrasonography had overestimation/underestimation rates of 7/5, 4/4 and 8/3%, respectively. The sensitivity rates for the three techniques were 72, 78, and 83%, respectively, and the specificity rates were 92, 95, and 89%, respectively. There were no statistically significant differences among the three endoscopic techniques. Clinical utility of magnifying endoscopy with narrow band imaging does not seem to be significantly different from that of non-magnifying high-resolution endoscopy or high-frequency endoscopic ultrasonography in predicting the depth of superficial esophageal squamous cell carcinoma. Magnifying endoscopy with narrow band imaging may have potential to reduce overestimation risks of non-magnifying high-resolution endoscopy or high-frequency endoscopic ultrasonography.

Successful Treatment of Stricture of Duct-to-Duct Biliary Anastomosis After Living-Donor Liver Transplantation of the Left Lobe: A Case Report.

Biliary complications, such as stricture or obstruction, after living-donor liver transplantation (LDLT) remain major problems to be solved. Magnetic compression anastomosis (MCA) is a minimally invasive method of biliary anastomosis without surgery in patients with biliary stricture or obstruction. A 66-year-old woman had undergone LDLT for end-stage liver disease for primary biliary cholangitis 20 months previously at another hospital. Computerized tomography showed dilation of the intrahepatic bile duct (B2). Because B2 was invisible with the use of endoscopic retrograde cholangiopancreatography, percutaneous transhepatic biliary drainage (PTBD) was performed for treatment of cholangitis. The rendezvous technique failed because a guidewire could not pass through the biliary stricture. Therefore, we decided to perform MCA. A parent magnet was endoscopically placed distally in the common bile duct of the stricture, and a daughter magnet attached to a guidewire was inserted proximally through the fistula tract of the PTBD. Both magnets were positioned across the stricture, and the 2 magnets were pulled to each other by magnetic power, to sandwich the stricture. By 14 days after MCA, a fistula between B2 and the common bile duct was created. At 28 days after MCA, the magnets were removed distally and a 16-French tube was placed across the fistula. At 7 months after MCA, that tube was removed. In conclusion, when a conventional endoscopic or percutaneous approach including the rendezvous technique fails, MCA is a good technique for biliary stricture after LDLT.

Surgical strategy for patients with pancreaticobiliary maljunction without choledocal dilatation.

It is well known that the frequency of an associated gallbladder cancer in patients with pancreaticobiliary maljunction (PBM) without congenital choledochal dilation (CCD) is very high, while that of bile duct cancer with CCD is remarkably high, and that of bile duct malignancy without CCD is low. However, recent statistical evaluations have demonstrated that the coincidence rates of gallbladder and bile duct cancer with CCD are 11.5% and 4.6%, respectively, whereas without CCD the rates are 57.1% and 4.1%, respectively. Rates of bile duct cancer with CCD are comparable to those without CCD. We have performed biliary reconstruction after resection of extrahepatic bile ducts along with the gallbladder for PBM patients who had neither CCD nor cancer. Our surgical strategy for these patients without CCD with PBM was assessed from K-ras point mutations and overexpression of p53 protein in the epithelia of the cancerous portions and non-neoplastic portions of the gallbladder and bile duct affected by PBM regardless of choledochal dilatation. The mutation rate in the non-neoplastic gallbladder epithelium without CCD was 80%, that of the bile duct without CCD 57%, not significantly different from the 50% and 40%, respectively, with CCD. The frequency of p53 overexpression in the non-neoplastic bile duct epithelium without CCD was 14%, comparable to the 11% in gallbladder epithelium with CCD. Judging from the statistical data and the molecular biological data, resection of an extrahepatic bile duct with the gallbladder should be the treatment of choice for carcinogenesis prevention.

Intrahepatic sarcomatous cholangiocarcinoma.

A 77-year-old man, diagnosed with a liver tumor, was referred to our hospital. Abdominal ultrasonography demonstrated a low echoic mass in the liver S2 region, and abdominal CT confirmed the presence of a round low-density mass 7 cm in diameter. Enhanced angio-computed tomography (CT) showed a ring-like form with a pale periphery. In the delayed phase of angio-CT, the inside of the mass was enhanced, showing septal stricture. Abdominal magnetic resonance imaging (MRI) revealed a heterogenous low intensity area in T1-weighted images, with a clear high intensity border becoming apparent in T2-weighted images. Stretching of the hepatic artery was evident on the arterial phase of angiography, while an avascular area was apparent in the lateral segment of the liver in the portal phase. Lateral segmentectomy was performed. The size of the tumor was 6 x 6 x 5 cm. On macroscopic cross section, it was white and clearly demarcated from the surrounding tissue. Microscopic observation of H&E-stained specimens did not show any glandular formation. The tumor consisted of an irregular fascicular arrangement of spindle-shaped and round cells with poor intercellular adhesion. While there was no region containing differentiated epithelial components, silver impregnation staining revealed structures resembling regenerating bile ducts. The tumor cells were positive for wide-keratin, and for vimentin staining. Tumor cells were carcinoembryonic antigen (CEA)-positive and alpha-feto protein (AFP)-negative. From the above findings, the tumor was judged to have originated from epithelium rather than from mesenchymal elements. The final diagnosis was intrahepatic cholangiocarcinoma with secondary sarcomatous transformation, rather than hepatocellular carcinoma.

Interferon treatment of chronic hepatitis C in patients with hemophilia or von Willebrand's disease in Japan.

Seven patients with chronic hepatitis C, six hemophiliacs and a patient with von Willebrand's disease, were treated with interferon-alpha (IFN-alpha). Either 9 MU of recombinant IFN-alpha 2a or 3 MU of lymphoblastoid alpha-IFN was administered daily for 2 weeks and then three times a week for 22 weeks. Liver histology, hepatitis C virus (HCV) genotypes, and HCV-RNA levels in sera were investigated in all of the patients before IFN therapy was instituted. Liver histology was classified by the European classification. HCV genotyping conformed to the so-called Okamoto's classification. HCV-RNA levels in sera were quantitated by competitive polymerase chain reaction, using mutant RNA. Liver histology, HCV genotype, and serum HCV-RNA level (copies/ml) in each patient were: patient 1, chronic persistent hepatitis, type II, 3 x 10(3) respectively; patient 2, chronic active hepatitis (CAH) 2a, type III, 6 x 10(4); patient 3, CAH2a, type IV, 2 x 10(5); patient 4, CAH2b, type I, 2 x 10(7); patient 5, CAH2b, type II, 8 x 10(4); patient 6, CAH2b, type III, 7 x 10(6); and patient 7, CAH2b, type IV, 1 x 10(7). Sustained elimination of HCV was achieved in patient 3 and temporary elimination was achieved in patients 1 and 2. The other patients showed persistent HCV-RNA positivity in sera both during and after IFN treatment. Poor responsiveness to IFN was observed in patients with relatively progressive liver histology and high levels of HCV viremia.

Psoas abscess and cellulitis of the right gluteal region resulting from carcinoma of the cecum.

Although retroperitoneal or psoas abscess is an unusual clinical problem, the insidious and occult characteristics of this abscess sometimes cause diagnostic delays, resulting in considerably high morbidity and mortality. In particular, psoas abscess caused by perforated colon carcinoma is uncommon. We report a case of psoas abscess caused by a carcinoma of the cecum. A 72-year-old Japanese woman was admitted to our hospital, with pain in the right groin and buttock. The pain had appeared 6 months before admission, and the symptoms had then been relieved by oral antibiotics. On March 25, 1999, inflammatory signs in the right buttock indicated localized cellulitis, and incision and drainage was performed at a local hospital. The patient was referred to our hospital on the same day. On admission to our hospital, computed tomography (CT) scan revealed a thick right-sided colonic wall and enlargement of the right ileopsoas muscle. Barium enema and colonofiberscopy revealed an ulcerated tumor occupying the entire circumference of the cecum. A retroperitoneal abscess and fistula had been formed by the retroperitoneal perforation of cecum carcinoma: surgical resection was performed after remission of the local inflammatory signs. Operative findings indicated that the cancerous lesion and its surrounding tissues were firmly attached to the right iliopsoas and major psoas muscle, and en-bloc resection, including adjacent muscular tissue, was performed. The fact that carcinoma of the colon could be a cause of psoas abscess and cellulitis in the gluteal region should be considered when an unexplained psoas abscess is diagnosed.

Cardiac metastasis from squamous cell carcinoma of gallbladder.

A 65-year-old woman was admitted to our hospital with the diagnosis of gallbladder tumor. Right extended hepatic lobectomy plus lymph node dissection of the hepatoduodenal ligament and left hepaticojejunostomy with Roux-en-Y reconstruction was performed in July, 1993. The gallbladder tumor was histologically proven to be squamous cell carcinoma. Seventeen months later, the patient experienced dyspnea and pitting edema of the lower legs and was admitted, in December 1994, with a diagnosis of heart failure. Despite intensive cardiac support, she died 12 days after the second admission. Autopsy revealed multiple cardiac tumors in the left and right ventricles, left atrium, left coronary artery, and left diaphragm. Histologically, these tumors were shown to be squamous cell carcinoma, considered to have metastasized from the primary gallbladder carcinoma. As neither local recurrence of the gallbladder carcinoma nor any lymph node metastasis was found, the cardiac metastasis of the gallbladder carcinoma may have occurred via the hematogenous route. Although rare, this route of cardiac metastasis of gallbladder carcinoma may be an important aspect of distant metastasis, which should be monitored for during follow-up after resection of the primary tumor.

[A study of DNA ploidy pattern, proliferation index and PCNA in duodenal carcinoma].

12 cases of duodenal carcinoma were studied for nuclear DNA ploidy patterns, the proliferation index (PI), proliferating cell nuclear antigen (PCNA) positive score (1 = 0-25%, 2 = 26-50%, 3 = 51-75%, 4 = 76-100%) and PCNA positive rate. DNA aneuploidy was observed in 9 cases (75%) and PCNA staining was positive in 11 cases (91.6%). DNA ploidy patterns, PI, PCNA positive scores and positive rates were not related to each other. No relationship DNA ploidy patterns for PCNA positive scores and PCNA positive rates could be found. The relationship between PI and PCNA positive score was found not to be significant (P less than 0.10). PI was revealed to correlate significantly (P less than 0.05) to PCNA positive rate.

[Local spread of carcinoma of the esophagus by perineural invasion].

For clarification of the clinico-pathological features of carcinoma of the esophagus by perineural invasion (pni), 107 resected specimens were histologically examined. A correlation between pni and other findings, including clinical results, was sought. Pni was found in 31 patients (29.0%). It was found in no cases without adventitial cancerous invasion, at 26.3% in a1, 36.5% in a2 and 66.7% in a3. Pni would thus appear to be closely correlated with the depth of invasion. It also showed correlation with lymph-canal invasion but not with venous invasion or lymph node metastasis. Pni positivity was the same regardless of patient's age and sex, as well as tumor size, location and histological differentiation. In patients who had undergone preoperative radiotherapy, lymph-canal and venous invasion were noted to have markedly decreased but not pni. Curative resection was carried out in 57.9% of the pni negative patients and in 32.3% of the pni positive. Local recurrence was observed in 30.0% of pni positive and only 4.5% of negative cases. The cumulative survival rate was not significantly less in positive compared to negative patients.

Hyperplastic polyp of the gallbladder in a child.

We report a case of hyperplastic polyp of the gallbladder in a 6-year-old girl, successfully treated by laparoscopic cholecyctectomy after a 2-year follow-up from the original diagnosis. On her first admission, serum amylase level was very high, so that congenital pancreaticobiliary maljunction (PBM) was suspected. Although it became clear afterwards that the high serum amylase level was derived from a mumps infection, the diagnosis of PBM was not excluded until intraoperative cholangiography was conducted. The tumor in the gallbladder had doubled in size in 2 years. It was not possible to obtain biopsy specimens for histological diagnosis, so the risk of the tumor being malignant could not be completely excluded until surgical resection had been carried out. In spite of the rapid tumor growth, no neoplastic features were seen in the tumor by histopathological examination of the resected specimen; thus, a diagnosis of a hyperplastic polyp of the gallbladder was made.

Submucosal dermoid cyst of the rectum: report of a case.

Despite the relatively common incidence of sacrococcygeal dermoids, rectal cysts are uncommon. We report the case of a submucosal dermoid cyst occurring in the rectum. A 30-year-old woman visited the Gynecology Department because of pregnancy. A pelvic tumor was accidentally found during the checkup after miscarriage. A barium enema showed an anterior shift of the rectum by the presence of the tumor. Computed tomography and magnetic resonance imaging revealed a tumor located posterior to the rectum occupying almost the entire pelvic cavity, and the tumor was resected. The tumor was located in the submucosal layer of the posterior rectal wall and was well circumscribed. The resected tumor was a cyst entirely covered with a fibrous and firm capsule, which was filled with an amorphous white creamy substance. The histological findings showed the cyst consisting of a keratinizing stratified squamous epithelium with sebaceous gland and hair follicles, which was compatible with benign cystic teratoma. Primary rectal teratoma is very rare and only 36 cases have been reported in the literature worldwide. Furthermore, while the majority of cases were polypoid-shaped dermoid cysts protruding into the rectal lumen, only 3 cases were submucosal dermoid cysts. Therefore, such cases are considered to be extremely rare.