Clinical significance of intracranial hemorrhage after thrombectomy detected solely by magnetic resonance imaging and not by computed tomography.

BACKGROUND AND OBJECTIVE: Whether intracranial hemorrhage (ICH) detected using magnetic resonance imaging (MRI) affects the clinical outcomes of patients with large-vessel occlusion (LVO) treated with mechanical thrombectomy (MT) remains unclear. This study investigated the clinical features of ICH after MT detected solely by MRI. METHODS: This was a retrospective analysis of patients with acute ischemic stroke and occlusion of the internal carotid artery or middle cerebral artery treated with MT between April 2011 and March 2021. Among 632 patients, patients diagnosed with no ICH using CT, with a pre-morbid modified Rankin Scale (mRS) score ≤ 2, and those who underwent MRI including T2* and computed tomography (CT) within 72 h from MT were enrolled. The main outcomes were the association between ICH detected solely by MRI and clinical outcomes at 90 days. Poor clinical outcomes were defined as mRS score > 2 at 90 days after onset. RESULTS: Of the 246 patients, 29 (12%) had ICH on MRI (MRI-ICH(+)), and 217 (88%) were MRI-ICH(-). There was no significant difference between number of patients with MRI-ICH(+) experiencing poor (10 [12%]) and favorable (19 [12%]) outcomes. The mRS score at 90 days between patients with MRI-ICH (+) and MRI-ICH(-) was not significantly different (2 [1-4] vs. 2 [1-4], respectively). Higher age and lower ASPECTS were independent risk factors for poor outcomes, as shown by multivariate regression analysis. MRI-ICH(+) status was not associated with poor outcomes. CONCLUSIONS: ICH detected by MRI alone did not influence clinical outcomes in patients with LVO treated with MT.

The effect of asymptomatic intracranial hemorrhage after mechanical thrombectomy on clinical outcome.

BACKGROUND AND OBJECTIVE: Whether asymptomatic intracranial hemorrhage (ICH) affects the clinical outcomes in patients with acute large vessel occlusion treated with mechanical thrombectomy (MT) remains unclear. This study aimed to address this uncertainty. METHODS: We retrospectively analyzed patients with acute ischemic stroke and internal carotid or middle cerebral (M1 segment) artery occlusion treated with MT between April 2011 and March 2021 at a single center. All patients had a premorbid modified Rankin scale (mRS) score ≤ 2 and an anterior circulation occlusion and underwent magnetic resonance imaging at admission. Asymptomatic ICH was defined as ICH without symptomatic ICH defined by the SITS-MOST criteria. A favorable outcome was defined as an mRS score ≤ 2 at 90 days after stroke onset. RESULTS: Our study included 349 patients; 62% were men, the median age was 76 [67-83] years, and the median National Institutes of Health Stroke Scale (NIHSS) score was 15 [8-21]. As determined via computed tomography, 103 (30%) patients had ICH (20 symptomatic and 83 asymptomatic). The favorable outcome rate was significantly lower for asymptomatic vs. no ICH (30% vs. 67%, p < 0.01). In a multivariate regression analysis, a high NIHSS score (odds ratio [OR], 1.06; 95% confidence interval [CI], 1.02-1.10; p < 0.01) and low Alberta Stroke Program Early CT Score (OR, 0.78; 95% CI, 0.65-0.92; p < 0.01) were independent risk factors for ICH. CONCLUSIONS: Asymptomatic ICH is associated with poor clinical outcome at 90 days after stroke onset.

Experimental and Theoretical Studies on Cobalt-Catalyzed Regioselective Hydrosilylation of Tetrafluorinated Cyclohexa-1,3-dienes.

Cyclohexa-1,3-dienes bearing a tetrafluoroethylene group underwent highly regioselective hydrosilylation in the presence of 1-10 mol % Co2(CO)8 in 1,2-dichloroethane under mild conditions (reflux, 3 h), which led to an abundant yield of homoallylsilanes. Mechanistic studies proved that the reaction proceeds as per the modified Chalk-Harrod mechanism; via DFT calculation, the reason for homoallylsilanes being exclusively obtained was demonstrated. The formal synthesis of a tetrafluorinated negative-type liquid crystal demonstrated the synthetic utility of such hydrosilylation.

A differential detailed diffusion-weighted imaging-ASPECTS for cerebral infarct volume measurement and outcome prediction.

BACKGROUND: Diffusion-weighted imaging-Alberta Stroke Program Early Computed Tomography Score (DWI-ASPECTS) has been used to estimate infarct core volume in acute stroke. However, the same and indiscriminate score deduction for punctate or confluent DWI high-intensity lesion might lead to variation in performance. AIMS: To develop and evaluate a differential detailed DWI-ASPECTS method in comparison with the conventional DWI-ASPECTS in core infarct volume measurement and clinical outcome prediction. METHODS: We retrospectively recruited patients with acute ischemic stroke (AIS) treated with endovascular treatment between April 2013 and October 2019. In differential detailed DWI-ASPECTS, restricted diffusion lesion that was punctate or less than half of a cortical region (M1-M6) would not lead to subtraction of point. A favorable outcome was modified Rankin Scale score ⩽2 at 90 days after stroke onset. RESULTS: Among 298 AIS patients, mean age was 75 years (interquartile range (IQR) 67-82), and 194 patients (65%) were males. Mean infarct core volume was 11 mL (IQR 3-37). Overall, the score by detailed DWI-ASPECTS was significantly higher than conventional DWI-ASPECTS (8 (7-9) vs. 7 (5-9); P < 0.01). The detailed DWI-ASPECTS resulted in a higher correlation coefficient (r) for core infarct volume estimation than the conventional DWI-ASPECTS (r = 0.832 vs. 0.773; P < 0.01). Upon re-classification of those scored ⩽6 in conventional DWI-ASPECTS (n = 134) by detailed DWI-ASPECTS, the rate of favorable outcome in patients with detailed DWI-ASPECTS >6 was significantly higher than those with ⩽6 (29 (48%) vs. 14 (19%); P < 0.01). CONCLUSIONS: Detailed DWI-ASPECTS appeared to provide a more accurate infarct core volume measurement and clinical outcome correlation than conventional DWI-ASPECTS among AIS patients treated with endovascular therapy.

[A case of neurosyphilis presenting as bilateral temporal, cortical and subcortical encephalitis].

A 37-year-old man who had a low grade fever for 5 days admitted to our hospital due to disturbance of consciousness and seizure. Brain MRI showed abnormal hyperintensity in the bilateral temporal lobes, cortical and subcortical lesions on fluid-attenuated inversion recovery image. Treponemal and non-treponemal specific antibodies were positive in serum and cerebrospinal fluid, therefore he was diagnosed as having neurosyphilis. Treatment with intravenous penicillin G and metylpredonisolone improved his clinical symptons, imaging abnormalities and CSF findings. Patients of neurosyphilis with mesiotemporal encephalitis show common features such as young age, HIV-negative, subacute cognitive impairment and seizure, as seen in our case. Early diagnosis of neurosyphilis and appropriate treatment make clinical improvement, however the clinical diagnosis of neurosyphilis is sometime difficult because most patients present with disturbance of consciousness or seizure. The possibility of neurosyphilis should be considered when MRI results indicate temporal abnormalities.

Class III ß-Tubulin Expression Is of Value in Selecting nab -Paclitaxel and Gemcitabine as First-Line Therapy in Unresectable Pancreatic Cancer.

OBJECTIVES: Nab -paclitaxel and gemcitabine (GnP) or FOLFIRINOX (a combination of leucovorin, fluorouracil, irinotecan, and oxaliplatin [FFX]) is currently recognized as the standard first-line regimen for unresectable pancreatic ductal adenocarcinoma (PDAC). Class III ß-tubulin (TUBB3) has the potential to predict resistance to taxane in various tumors; therefore, this study aimed to clarify whether TUBB3 is a predictive marker for GnP response. METHODS: We retrospectively reviewed 113 patients with PDAC who received GnP or FFX as first-line chemotherapy and examined immunohistochemically the TUBB3 expression in specimens obtained by endoscopic ultrasound-guided fine-needle aspiration. RESULTS: High TUBB3 expression was associated with a significantly lower disease control rate ( P = 0.017) and shorter progression-free survival (PFS) ( P = 0.019), and multivariate analysis revealed that TUBB3 expression was an independent variable for PFS in the GnP first-line group ( P = 0.045). In addition, in the FFX first-line group, TUBB3 expression was not correlated with PFS or overall survival (OS). In all 113 patients, TUBB3 expression was not also associated with OS. CONCLUSIONS: Class III ß-tubulin might be a predictive factor for the response of GnP, but not a prognostic factor for OS, helping the selection of an optimized first-line chemotherapy regimen for unresectable PDAC.

Fluid-Attenuated Inversion Recovery May Serve As a Tissue Clock in Patients Treated With Endovascular Thrombectomy.

Background and Purpose: We investigated whether the signal change on fluid-attenuated inversion recovery (FLAIR) can serve as a tissue clock that predicts the clinical outcome after endovascular thrombectomy (EVT), independently of the onset-to-admission time. Methods: Consecutive patients with acute stroke treated with EVT between September 2014 and December 2018 were enrolled. Based on the parenchymal signal change on FLAIR, patients were classified into FLAIR-negative and FLAIR-positive groups. The clinical characteristics, imaging findings, EVT parameters, and the intracranial hemorrhage defined as Heidelberg Bleeding Classification ≥1c hemorrhage (parenchymal hemorrhage, intraventricular hemorrhage, subarachnoid hemorrhage, and/or subdural hemorrhage) were compared between the 2 groups. A modified Rankin Scale score 0 to 1 at 3 months was considered to represent a good outcome. Results: Of the 227 patients with EVT during the study period, 140 patients (62%) were classified into the FLAIR-negative group and 87 (38%) were classified into the FLAIR-positive group. In the FLAIR-negative group, the patients were older (P=0.011), the onset-to-image time was shorter (P<0.001), the frequency of cardioembolic stroke was higher (P=0.006), and the rate of intravenous thrombolysis was higher (P<0.001) in comparison to the FLAIR-positive group. Although the rate of complete recanalization after EVT did not differ between the 2 groups (P=0.173), the frequency of both any-intracranial hemorrhage and Heidelberg Bleeding Classification ≥1c hemorrhage were higher in the FLAIR-positive group (P=0.004 and 0.011). At 3 months, the percentage of patients with a good outcome (FLAIR-negative, 41%; FLAIR-positive, 27%) was significantly related to the FLAIR signal change (P=0.047), while the onset-to-image time was not significant (P=0.271). A multivariate regression analysis showed that a FLAIR-negative status was independently associated with a good outcome (odds ratio, 2.10 [95% CI, 1.02­4.31], P=0.044). Conclusions: A FLAIR-negative status may predict the clinical outcome more accurately than the onset-to-admission time, which may support the role of FLAIR as a tissue clock.

One-step versus two-step distal self-expandable metal stent placement: A multicenter prospective randomized trial.

BACKGROUND AND AIM: Two methods of transpapillary covered self-expandable metal stent (SEMS) placement are used for distal malignant biliary obstruction (MBO): after initial drainage by plastic stent (two-step method) and without previous drainage (one-step method). METHODS: In total, 90 patients with unresectable pancreatic cancer and distal MBO were enrolled in this prospective multicenter randomized study and allocated to one-step (n = 45) and two-step (n = 45) groups. The main outcome was the time to recurrent biliary obstruction (TRBO). Secondary outcomes were the rates of early and late adverse events, survival time, the time required for bilirubin level reduction, and cost-effectiveness. RESULTS: The median TRBO did not differ significantly between the one-step and two-step groups (not available vs 314 days, P = 0.134). SEMS migration occurred significantly more frequently in the two-step group (14.3% vs 0%, P = 0.026). No significant difference was observed between groups in early (7.3% vs 14.3%, P = 0.483) or late (12.2% and 11.9%, P = 1) adverse events other than RBO, survival time (P = 0.104), or the median number of days required to reach a bilirubin level considered to be acceptable for chemotherapy administration (<3 mg/dL; P = 0.881). The total costs of stent placement and reintervention were significantly lower in the one-step SEMS group (3347 vs 5465 US dollars, P < 0.001). CONCLUSIONS: The superiority of TRBO with two-step SEMS placement was not demonstrated. One-step SEMS placement might be a promising method from the viewpoints of cost-effectiveness and less invasiveness (UMIN-CTR clinical trial registration number: UMIN000016010).

Thrombectomy for Upper Extremity Artery Occlusion with Major Cerebral Artery Occlusion Using Mechanical Thrombectomy Devices for Acute Ischemic Stroke.

Objective: We report two cases of thrombectomy for upper extremity artery occlusion with major cerebral artery occlusion using mechanical thrombectomy devices for acute ischemic stroke. Case Presentations: Case 1 was a 79-year-old woman admitted for left internal carotid artery occlusion and left upper extremity artery occlusion. Case 2 was an 87-year-old woman admitted for left middle cerebral artery occlusion and bilateral upper extremity artery occlusion. After performing mechanical thrombectomy for the cerebral artery, we achieved good recanalization of the brachial artery using the same devices in Case 1 and Case 2. Conclusions: Thrombectomy using acute ischemic stroke mechanical thrombectomy devices for upper extremity artery occlusion is useful for recanalization.

Association between initial NIHSS score and recanalization rate after endovascular thrombectomy.

BACKGROUND: National institutes of Health Stroke Scale (NIHSS) score and the presence of successful recanalization are crucial determinants of clinical outcome in patients with major artery occlusion. However, it is unknown whether successful recanalization rate after endovascular therapy (EVT) depends on NIHSS score. METHODS: From our prospective EVT registry, data on patients with an occlusion at the internal carotid artery or middle cerebral artery were analyzed. Successful recanalization was judged as positive when reperfusion of the thrombolysis in cerebral infarction (TICI) scale ≥2b was observed. Successful recanalization rate was also evaluated based on the NIHSS score subgroups: 0-8, 9-16, 17-24, and >24. Multivariate regression analysis was used to evaluate the impact of NIHSS score on successful recanalization. RESULTS: We studied 183 patients (age 76 [68-83], male 110 [60%], NIHSS score 19 [14-24]). One hundred and forty-six (80%) patients had the successful recanalization. Patients achieved the recanalization had lower NIHSS score as 18 (12-23), contrary those failed it had higher NIHSS score as 24 (20-27) (p < .001). Successful recanalization rate was correlated to the NIHSS score grade; 100% in the NIHSS 0-8 group, 88% in 9-16, 81% in 17-24, and only 60% in >24 (p < .001). Multivariate regression analysis showed NIHSS score was an independent parameter of recanalization (odds ratio 0.905 [95%CI 0.837-0.979], p = .013). CONCLUSION: NIHSS score may serve as a predictor of successful recanalization. Recanalization is relatively easier in mild stroke than in those with severe stroke.

Aortogenic Embolic Stroke Diagnosed by a Pathological Examination of Endovascularly Removed Thrombus: An Autopsy Report.

Complex aortic atheroma is a high-risk factor for recurrent embolic stroke. An accurate identification of stroke etiology is clinically important; however, it can be challenging. A 91-year-old man with atrial fibrillation was diagnosed with cardioembolic stroke and treated with mechanical thrombectomy. The removed thrombus microscopically contained foamy cells, suggesting an atheroembolism. An autopsy revealed an atherosclerotic lesion with ulceration, located in the aortic arch. At the lesion, the plaque had microscopically ruptured into the lumen. We therefore concluded that the aortic atherosclerotic lesion was the embolic source. Removed thrombi should be pathologically examined even if a cardioembolic stroke is clinically suspected.

The absence of class III ß-tubulin is predictive of a favorable response to nab-paclitaxel and gemcitabine in patients with unresectable pancreatic ductal adenocarcinoma.

The combined administration of nab-paclitaxel and gemcitabine (nab-P + Gem) is a standard chemotherapy for unresectable pancreatic ductal adenocarcinoma (UR-PDAC); thus, a predictive biomarker to identify patients best suited for nab-P + Gem therapy would be useful. Class III ß-tubulin (TUBB3) has been reported to be a predictive marker for taxane resistance in various tumors. However, the correlation between TUBB3 expression and the response to nab-P + Gem in patients with UR-PDAC has not been evaluated. We retrospectively reviewed 75 patients with UR-PDAC who received nab-P + Gem. TUBB3 expression was examined immunohistochemically in specimens obtained by endoscopic ultrasound-guided fine needle aspiration (EUS-FNA). From 67 analyzable specimens that were available for TUBB3 staining, 14 (21%) were negative for TUBB3 immunostaining and 53 (79%) were positive. Patients with negative TUBB3 expression showed a significantly higher disease control rate (100% vs. 64.2%; P = .008) and longer progression-free survival (PFS); (7.1 months vs. 3.7 months; log-rank test, P = .036) than those of patients with positive. Furthermore, negative TUBB3 expression was an independent predictive marker of a prolonged PFS on multivariate analysis (hazard ratio, 2.41; 95% confidence interval, 1.11-5.24; P = .026). Our data indicate that an absence of TUBB3 expression in specimens obtained by EUS-FNA may be a favorable predictive marker of the response to nab-P + Gem in patients with UR-PDAC, highlighting its use as a potential new biomarker for treatment optimization.

Autoimmune Hemolytic Anemia Obscured by the Obstructive Jaundice Associated with IgG4-related Sclerosing Cholangitis in a Patient with Type 1 Autoimmune Pancreatitis: A Case Report and Review of the Literature.

Type 1 autoimmune pancreatitis (AIP) is a pancreatic manifestation of IgG4-retated disease that is often associated with IgG4-related sclerosing cholangitis (IgG4-SC). Autoimmune hemolytic anemia (AIHA) is an immune-related disease that causes hemolytic anemia. Although type 1 AIP/IgG4-SC and AIHA have a shared etiology as a presumed autoimmune disease, they rarely overlap, and their association has not been clarified. Secondary AIHA might not be diagnosed appropriately because the obstructive jaundice observed in type 1 AIP/IgG4-SC can obscure the presence of hemolytic jaundice. We herein report a case of type 1 AIP/IgG4-SC overlapping with secondary AIHA along with a review of the literature.

Novel characteristics of traction force in biliary self-expandable metallic stents.

BACKGROUND AND AIM: In recent years, knowledge concerning the mechanical properties of self-expandable metallic stents (SEMS) has increased. In a previous study, we defined traction force and traction momentum and reported that these characteristics are important for optimal stent deployment. However, traction force and traction momentum were represented as relative values and were not evaluated in various conditions. The purpose of the present study was to measure traction force in various situations assumed during SEMS placement. METHODS: Traction force and traction momentum were measured in non-stricture, stricture, and angled stricture models using in-house equipment. RESULTS: Stricture and angled stricture models had significantly higher traction force and traction momentum than those of the non-stricture model (stricture vs non-stricture: traction force, 7.2 N vs 1.4 N, P < 0.001; traction momentum, 237.8 Ns vs 62.3 Ns, P = 0.001; angled stricture vs non-stricture: traction force, 7.4 N vs 1.4 N, P < 0.001; traction momentum, 307.2 Ns vs 62.3 Ns, P < 0.001). Traction force was variable during SEMS placement and was categorized into five different stages, which were similar in both the stricture and angled stricture models. CONCLUSIONS: We measured traction force and traction momentum under simulated clinical conditions and demonstrated that strictures and the angular positioning of the stent influenced the traction force. Clinicians should be aware of the transition of the traction force and should schedule X-ray imaging during SEMS placement.

IgG4-related Sclerosing Cholangitis with No Biliary Stricture but Severe Thickening of the Bile Duct Wall.

We herein report a case of a 56-year-old man with IgG4-related sclerosing cholangitis (IgG4-SC) with no biliary stricture, but with a severely thickened bile duct wall. Contrast-enhanced computed tomography showed diffuse swelling of the pancreas and thickening of the common bile duct (CBD) wall with delayed enhancement. Obvious diffuse wall thickening of the CBD was observed on endoscopic ultrasonography. However, endoscopic retrograde cholangiography showed no biliary stricture in the CBD that had thickened. Although IgG4-SC has been classified by a stenotic lesion on cholangiography, we should be aware of some IgG4-SC cases showing only bile duct wall thickness without any biliary stricture.

Neuroendocrine carcinoma of the ampulla of Vater causing ectopic adrenocorticotropic hormone-dependent Cushing's syndrome.

Ectopic adrenocorticotropic hormone (ACTH) is rarely secreted by neuroendocrine tumors. Although neuroendocrine tumors may occur at any site in the gastrointestinal system, they very rarely occur in the ampulla of Vater and have a poor prognosis. The present study described the first Cushing's syndrome as a result of ectopic ACTH arising from the ampulla of Vater neuroendocrine carcinoma. A 69-year-old female was admitted with clinical features of Cushing's syndrome, confirmed biochemically by hypokalemia, and elevated levels of ACTH and cortisol. In further investigations, a tumor of the ampulla of Vater and liver metastases were detected. Pathological analysis of the biopsy confirmed a neuroendocrine carcinoma, which was immunohistochemically positive for chromogranin A, synaptophysin, cluster of differentiation 56 and ACTH. Therefore, the present study diagnosed a functional and metastatic neuroendocrine carcinoma of the ampulla of Vater with ectopic ACTH production causing Cushing's syndrome. The patient succumbed to mortality 4 months later, despite administration of combined chemotherapy with irinotecan and cisplatin.

Clinical features of acute obstructive suppurative pancreatic ductitis: A retrospective review of 20 cases.

BACKGROUND AND AIMS: The clinical features of acute obstructive suppurative pancreatic ductitis (AOSPD) have not been elucidated. We aimed to clarify the clinical features of AOSPD. METHODS: We retrospectively reviewed the clinical features of 20 patients with AOSPD at two tertiary referral centers between 1993 and 2012. We compared 17 AOSPD patients with chronic pancreatitis (CP) and 42 patients with acute-on-CP in terms of clinical characteristics, presentation, and laboratory and imaging findings. RESULTS: The etiology of AOSPD involved CP in 17 (85%) patients, pancreatic ductal adenocarcinoma in 2 (10%), and intraductal papillary mucinous neoplasm in 1 (5%). Endoscopic pancreatic drainage was effective in 19 (95%) patients. Body temperature was significantly higher in AOSPD with CP than acute-on-CP patients (median: 38.2 vs 36.9 °C; P < 0.001). Serum amylase levels at onset were significantly lower (median: 133 vs 364.5 U/L; P = 0.009), and C-reactive protein was significantly higher (median: 9.42 vs 1.06 mg/dL; P < 0.001) in AOSPD with CP patients. Enlargement of the pancreatic parenchyma (18 vs 93%; P < 0.001) and stranding of the surrounding fat (12 vs 93%; P < 0.001) on computed tomography were observed less frequently in patients with AOSPD with CP patients. The diameter of the main pancreatic duct was significantly greater in AOSPD with CP than acute-on-CP patients (median: 7 vs 5 mm; P = 0.006). CONCLUSIONS: The major etiology of AOSPD involved CP, and endoscopic pancreatic drainage was effective. The clinical features differ between AOSPD with CP and acute-on-CP.

New concept of traction force applied to biliary self-expandable metallic stents.

BACKGROUND AND STUDY AIMS: Various mechanical properties of self-expandable metallic stents (SEMSs) have been reported. They can be classified into the device behavior during and after deployment. While there have been several reports on the latter, information on the former is insufficient. During deployment, the position is maintained by retracting the delivery catheter. We propose that this pulling force be called the traction force and that the magnitude of traction force is termed the traction momentum. The aim of this study was to measure these parameters in order to clarify the properties of SEMSs in terms of their deployment. MATERIAL AND METHODS: The traction force, traction momentum, and shortening rate of 10 different SEMSs were measured. Traction force was measured using in-house equipment, and the shortening rate was determined by measuring the stents. RESULTS: The shortening rate was closely related to the stent structure. The traction force varied between 1.5 N and 9.4 N, and the traction momentum was significantly elevated in covered and braided stents. A high traction force did not imply a high traction momentum. CONCLUSIONS: A low or constant traction force and a minimal shortening rate significantly facilitated SEMS deployment to optimal positions. Traction force could be an important element for new ideal SEMS design.

Predictive factors for positive diagnosis of malignant biliary strictures by transpapillary brush cytology and forceps biopsy.

OBJECTIVE: The diagnostic yields of endoscopic transpapillary brush cytology and forceps biopsies for malignant biliary strictures (MBS) remain unclear and predictive factors for diagnosis have not been established. We aimed to clarify the diagnostic yields of both methods and the predictive factors METHODS: We reviewed 241 patients with biliary strictures who underwent transpapillary brush cytology (n = 202) or forceps biopsy (n= 208) between 2004 and 2014 at a single academic center. RESULTS: The sensitivity of forceps biopsy for MBS was significantly higher than that of brush cytology [60.6% (97/160) vs 36.1% (57/158), P < 0.01). The sensitivity of forceps biopsy was significantly higher in diagnosing bile duct cancer than pancreatic cancer [78.8% (52/66) vs 42.4% (28/66), P < 0.01). Multivariate analysis revealed that serum total bilirubin (TB) level (T-Bil) ≥ 4 mg/dL [odds ratio (OR) 2.506, 95% confidence interval (CI): 1.139-5.495, P = 0.022) was an independent predictor for positive diagnosis by brush cytology, while bile duct cancer (OR 4.926, 95% CI 2.183-11.111, P < 0.001), stricture length ≥ 30 mm (OR 2.941, 95% CI 1.119-7.752, P = 0.029) and TB ≥ 4 mg/dL (OR 2.252, 95% CI 1.052-4.831, P = 0.037) were significant indicators of a positive diagnosis by forceps biopsy. CONCLUSIONS: Endoscopic transpapillary forceps biopsy shows higher sensitivity than that of brush cytology for MBS. Bile duct cancer, stricture length ≥ 30 mm and TB ≥ 4 mg/dL are good indicators of forceps biopsy.