Hirotoshi Ishiwatari

Multicenter retrospective study of endoscopic ultrasound-guided biliary drainage for malignant biliary obstruction in Japan

Endoscopic ultrasound‐guided biliary drainage (EUS‐BD) is considered to be an effective salvage procedure for failed endoscopic retrograde cholangiopancreatography in patients with unresectable malignant biliary obstruction. The aim of this retrospective study was to evaluate the efficacy and feasibility of EUS‐BD.

Aberrant Crypt Foci: Detection, Gene Abnormalities, and Clinical Usefulness

Human aberrant crypt foci (ACF) were first identified as lesions consisting of large thick crypts in colonic mucosa of surgical specimens after staining with methylene blue. Previously we succeeded in identifying ACF by using magnifying endoscopy and analyzed the number, size, and dysplastic features of ACF in normal controls and patients with adenoma or cancer patients. On the basis of these analyses, we strongly suggested that ACF, particularly dysplastic ACF, are precursor lesions of the adenoma-carcinoma sequence in humans. In most sporadic ACF, K-ras mutations were positive, but APC mutations were negative irrespective of nondysplastic or dysplastic features. Conversely, in most ACF from familial adenomatous polyposis patients, APC mutations were positive but K-ras mutations were negative. These results may suggest that the molecular mechanism of sporadic colon carcinogenesis is not necessarily the same as that of familial adenomatous polyposis. It was shown that ACF acquired resistance to apoptosis induced by bile salts, whereas normal colonic epithelial cells are turning over consistently by apoptosis. This apoptosis resistance was closely associated with glutathione S-transferase P1-1 expression. One of the most important clinical applications of ACF observation with magnifying endoscopy is its use as a target lesion for chemoprevention. Because ACF are tiny lesions, they should be eradicated during a short time by administration of chemopreventive agents. In fact, we performed an open chemopreventive trial of sulindac and found that the number of ACF was reduced markedly in 2 months. We currently are proceeding with a randomized double-blind trial targeting ACF.

Rapid on-site evaluation by endosonographer during endoscopic ultrasound-guided fine needle aspiration for pancreatic solid masses.

Endoscopic ultrasound‐guided fine needle aspiration (EUS‐FNA) is an established diagnostic method for patients with suspected pancreatic ductal carcinoma. Rapid on‐site evaluation (ROSE) has been reported to improve the accuracy. However, an on‐site cytopathologist is not routinely available in many institutions. One of the solutions may be ROSE by endosonographer. The aim was to examine whether diagnostic accuracy increases through ROSE by endosonographer using our cytological criteria.

Treatment of pancreatic fibrosis with siRNA against a collagen-specific chaperone in vitamin A-coupled liposomes

Background and objective Fibrosis associated with chronic pancreatitis is an irreversible lesion that can disrupt pancreatic exocrine and endocrine function. Currently, there are no approved treatments for this disease. We previously showed that siRNA against collagen-specific chaperone protein gp46, encapsulated in vitamin A-coupled liposomes (VA-lip-siRNAgp46), resolved fibrosis in a model of liver cirrhosis. This treatment was investigated for pancreatic fibrosis induced by dibutyltin dichloride (DBTC) and cerulein in rats. Methods Specific uptake of VA-lip-siRNAgp46, conjugated with 6′-carboxyfluorescein (FAM) by activated pancreatic stellate cells (aPSCs), was analysed by fluorescence activated cell sorting (FACS). Intracellular distribution of VA-lip-siRNAgp46-FAM was examined by fluorescent microscopy. Suppression of gp46 expression by VA-lip-siRNAgp46 was assessed by immunoblotting. Collagen synthesis in aPSCs was assayed by dye-binding. Specific delivery of VA-lip-siRNAgp46 to aPSCs in DBTC rats was verified following intravenous VA-lip-siRNA-FAM and 3H-VA-lip-siRNAgp46. The effect of VA-lip-siRNA on pancreatic histology in DBTC- and cerulein-treated rats was determined by Azan-Mallory staining and hydroxyproline content. Results FACS analysis revealed specific uptake of VA-lip-siRNAgp46-FAM through the retinol binding protein receptor by aPSCs in vitro. Immunoblotting and collagen assay verified knockdown of gp46 and suppression of collagen secretion, respectively, by aPSCs after transduction of VA-lip-siRNAgp46. Specific delivery of VA-lip-siRNAgp46 to aPSCs in fibrotic areas in DBTC rats was confirmed by fluorescence and radioactivity 24 h after the final injection. 10 systemic VA-lip-siRNAgp46 treatments resolved pancreatic fibrosis, and suppressed tissue hydroxyproline levels in DBTC- and cerulein-treated rats. Conclusion These data suggest the therapeutic potential of the present approach for reversing pancreatic fibrosis.

Early use of double-guidewire technique to facilitate selective bile duct cannulation: the multicenter randomized controlled EDUCATION trial.

BACKGROUND AND STUDY AIMS There are no guidelines for the timing of conversion from a single-guidewire to a double-guidewire technique to facilitate selective bile duct cannulation and reduce post-endoscopic retrograde cholangiopancreatography pancreatitis (PEP), when using wire-guided cannulation. We investigated whether early conversion to the double-guidewire method, at first unintentional insertion of a guidewire into the pancreatic duct, facilitated selective bile duct cannulation and reduced PEP compared with repeated single-guidewire attempts. PATIENTS AND METHODS A multicenter prospective randomized controlled trial included 274 patients with a naive papilla, undergoing endoscopic retrograde cholangiography (ERC) using wire-guided cannulation in whom there was unintentional insertion of the guidewire into the pancreatic duct. With the guidewire still in the duct, patients were randomly assigned to undergo the double-guidewire technique or repeated single-wire cannulation. Main outcomes were success rates for selective bile duct cannulation and PEP frequency. RESULTS Success rates for selective bile duct cannulation within 10 attempts and 10 minutes were 75 % and 70 %, respectively, for the early double-guidewire (EDG) and repeated single-guidewire (RSG) cannulation groups (relative rate 1.07, 95 % confidence interval [95 %CI] 0.93 - 1.24, P = 0.42). Corresponding final selective bile duct cannulation rates were 98 % and 97 % (relative rate 1.01, 95 %CI 0.97 - 1.05, P = 1.00). PEP rates were 20 % and 17 %, respectively, for the EDG and RSG cannulation groups (relative risk 1.17, 95 %CI 0.71 - 1.94, P = 0.53). Double-guidewire cannulation was more effective in patients with malignant biliary stricture (relative rate 1.36, 95 %CI 1.05 - 1.77, P = 0.02). CONCLUSIONS During therapeutic ERC using wire-guided cannulation, converting to a double-guidewire technique neither facilitated selective bile duct cannulation nor decreased PEP incidence compared with repeated use of a single-wire technique.

Chemoprevention of colorectal cancer

Colorectal cancer is a disease with a high mortality rate and it has been increasing in prevalence worldwide. Chemoprevention, as well as primary and secondary prevention, for colorectal cancer have attracted much attention. Many chemopreventive trials have been performed, and several agents, including nonsteroidal antiinflammatory drugs, such as aspirin and sulindac, cyclooxygenase-2 selective inhibitors, such as celecoxib, vitamin D, folate, and calcium, have been shown to have some effect. In these chemopreventive trials, the targeted lesions used for evaluation were mainly polyps. However, the chemopreventive effects of some agents on polyps may require several years to evaluate. Further, larger polyps may not be susceptible to chemopreventive agents. Aberrant crypt foci (ACF) are tiny lesions at the earliest stage of colorectal carcinogenesis, which consist of large, thick crypts identified by dense, methylene blue staining. We succeeded in identifying human ACF in situ using magnifying endoscopy and found that the number of ACF, particularly dysplastic ACF, increased significantly from normal subjects to adenoma patients and then to cancer patients. We also found that the number, size, and dysplastic features of ACF are significantly correlated with the number of adenomas in adenoma patients. Thus, it was surmised that ACF are precursor lesions of the adenoma-carcinoma sequence in humans and that ACF may be the most appropriate lesions as targets for chemoprevention. We have shown that the number of ACF was significantly reduced in patients treated with sulindac. We are currently proceeding with a randomized, double-blind, chemopreventive trial targeting ACF.

A Phase I Trial of Arterial Infusion Chemotherapy with Gemcitabine and 5-Fluorouracil for Unresectable Advanced Pancreatic Cancer after Vascular Supply Distribution via Superselective Embolization

BACKGROUND We previously reported that arterial infusion chemotherapy improved the response rate and survival of the patients with pancreatic cancer at advanced stages in an open trial. We conducted a Phase I trial of arterial infusion chemotherapy with gemcitabine and 5-fluorouracil for advanced pancreatic cancer after vascular supply distribution via superselective embolization. METHODS Patients were treated after arterial embolization for hemodynamic change to restrict the blood flow into the pancreas (mainly to the great pancreatic artery and the caudal pancreatic artery). Arterial infusion chemotherapy consisted of gemcitabine in doses that were increased from 600 to 1000 mg/m(2) in subsequent cohorts on Day 1 plus continuous infusion of 5-fluorouracil 300 mg/m(2)/day on Days 1-5 every 2 weeks. Result Twelve patients were enrolled. The maximum tolerated dose of gemcitabine was determined to be Level 3 (1000 mg/m(2)). Only very mild hematological and non-hematological toxicities were noted. The overall response rate was 33.3%. The median survival time was 22.7 (95% CI; 9.5-24.5) months and the 1- and 2-year overall survival rates were 83.3 and 25.0%, respectively. CONCLUSION Arterial infusion chemotherapy using 1000 mg/m(2) gemcitabine on Day 1 and 300 mg/m(2)/day 5-fluorouracil on Days 1-5 every 2 weeks warrants a Phase II study.

Recurrence of primary hepatic carcinoid tumor in the remnant liver 13 yr after resection.

We report here a case of primary hepatic carcinoid tumor (PHCT) recurring in the remnant liver 13 yr and 10 mo after first resection. A 70-yr-old man developed four hypervascular tumors in the liver in December 2003. He had undergone curative left-lobe hepatectomy for PHCT in February 1990. Histopathological examination of the tumor biopsy specimen showed that the tumor was composed of uniform round-to-oval cells with solid arrangement and the tumor cells stained positive for chromogranin A, synaptophysin, and neuron-specific enolase. We diagnosed this case as an intrahepatic metastasis of PHCT with a long latency period, based on the fact that no primary site of carcinoid tumor could be found despite intensive examination and the immunohistochemical findings of the resected tumors were essentially same as those of PHCT in 1990. Although PHCT is reported to have a more favorable prognosis than other hepatic cancer or metastatic carcinoid tumor in the liver, long-term observation is recommended.

EUS-guided celiac plexus neurolysis by using highly viscous phenol-glycerol as a neurolytic agent (with video)

4 EUS-guided celiac plexus neurolysis (EUS-CPN) is considered to be a reliable treatment for cancer-related pain. However, inadequate distribution of the neurolytic agent to the celiac plexus (CP) has been presumed to contribute to the failure of pain relief. Indeed, it has been reported that the distribution of the neurolytic agent to only the left side of the celiac artery (CA) (as assessed by CT) is a significant predictor of negative response to EUSCPN. Generally, the injected neurolytic agent in EUS-CPN is more likely to flow into the left side of the CA. Further, it often spreads extensively beyond the CP and throughout the retroperitoneal cavity. These tendencies probably relate to the left lateral decubitus position during the procedure and the supine position after the procedure, which allow the neurolytic agent to spread extensively by gravity, preventing it from remaining near the CA. We hypothesized that a highly viscous neurolytic agent would remain around the CP and provide better pain relief. Ethanol and phenol are the neurolytic agents commonly used in CPN. Although they permanently destroy the CP, they have low viscosities. A representative highly viscous neurolytic agent is glycerol, which has been recommended

Phenol-based endoscopic ultrasound-guided celiac plexus neurolysis for East Asian alcohol-intolerant upper gastrointestinal cancer patients: A pilot study

AIM To investigate the effectiveness of phenol for the relief of cancer pain by endoscopic ultrasound-guided celiac plexus neurolysis (EUS-CPN). METHODS Twenty-two patients referred to our hospital with cancer pain from August 2009 to July 2011 for EUS-CPN were enrolled in this study. Phenol was used for 6 patients with alcohol intolerance and ethanol was used for 16 patients without alcohol intolerance. The primary endpoint was the positive response rate (pain score decreased to ≤ 3) on postoperative day 7. Secondary endpoints included the time to onset of pain relief, duration of pain relief, and complication rates. RESULTS There was no significant difference in the positive response rate on day 7. The rates were 83% and 69% in the phenol and ethanol groups, respectively. Regarding the time to onset of pain relief, in the phenol group, the median pre-treatment pain score was 5, whereas the post-treatment scores decreased to 1.5, 1.5, and 1.5 at 2, 8, and 24 h, respectively (P < 0.05). In the ethanol group, the median pre-treatment pain score was 5.5, whereas the post-treatment scores significantly decreased to 2.5, 2.5, and 2.5 at 2, 8, and 24 h, respectively (P < 0.01). There was no significant difference in the duration of pain relief between the phenol and ethanol groups. No significant difference was found in the rate of complications between the 2 groups; however, burning pain and inebriation occurred only in the ethanol group. CONCLUSION Phenol had similar pain-relieving effects to ethanol in EUS-CPN. Comparing the incidences of inebriation and burning pain, phenol may be superior to ethanol in EUS-CPN procedures.