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Dive into the research topics where Spencer Cheng is active.

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Featured researches published by Spencer Cheng.


Digestive and Liver Disease | 2012

Treatment of malignant gastroduodenal obstruction with a nitinol self-expanding metal stent: an international prospective multicentre registry.

Guido Costamagna; Andrea Tringali; Julius Spicak; Massimiliano Mutignani; John M. Shaw; André G. Roy; Erik Johnsson; Eduardo Guimarães Hourneaux de Moura; Spencer Cheng; Thierry Ponchon; Max Bittinger; Helmut Messmann; Horst Neuhaus; Brigitte Schumacher; Rene Laugier; Juha Saarnio; Francisco Igea Ariqueta

BACKGROUND Duodenal stenting has become a broadly accepted first line of treatment for patients with advanced malignant gastroduodenal obstruction as these patients are difficult to treat and are poor surgical candidates. AIMS To document duodenal stent performance for palliative management of malignant gastroduodenal obstruction. METHODS Multicentre, single arm, prospective registry documenting peroral endoscopic duodenal stenting procedures in 202 patients. RESULTS Technical success achieved in 98% (CI, 95%, 99%) of stent placements. Increase of Gastric Outlet Obstruction Score by at least 1 point compared to baseline was achieved in 91% (CI, 86%, 95%) of patients persisting for a median of 184 days (CI, 109, 266). By day 5 (CI, 4, 6) after stent placement, 50% of patients experienced a score increase of at least 1 point. Improvement from 14% of patients at baseline tolerating soft solids or low residue/normal diet to 84% at 15 days, 86% at 30 days, 81% at 90 days, 79% at 180 days, and 70% at 270 days. Complications included stent ingrowth and/or overgrowth (12.4%), transient periprocedural symptoms (3%), bleeding (3%), stent migration (1.5%), and perforation (0.5%). CONCLUSIONS Safety and effectiveness of duodenal stenting for palliation of malignant gastroduodenal obstruction was confirmed in the largest international prospective series to date.


Arquivos De Gastroenterologia | 2006

Watermelon stomach: clinical aspects and treatment with argon plasma coagulation

Dalton Marques Chaves; Paulo Sakai; Cláudio Vasconcelos Oliveira; Spencer Cheng; Shinichi Ishioka

BACKGROUND Gastric antral vascular ectasia is a disorder whose pathogenetic mechanism is unknown. The endoscopic treatment with argon plasma coagulation has been considered one of the best endoscopic therapeutic options. AIM To analyze the endoscopic and clinical features of gastric antral vascular ectasia and its response to the argon plasma coagulation treatment. PATIENTS AND METHODS Eighteen patients were studied and classified into two groups: group 1--whose endoscopic aspect was striped (watermelon) or of the diffuse confluent type; group 2--diffuse spotty nonconfluent endoscopic aspect. RESULTS Group 1 with eight patients, all having autoimmune antibodies, but one, whose antibodies were not searched for. Three were cirrhotic and three had hypothyroidism. All had gastric mucosa atrophy. In group 2, with 10 patients, all had non-immune liver disease, with platelet levels below 90,000. Ten patients were submitted to argon plasma coagulation treatment, with 2 to 36 months of follow-up. Lesions recurred in all patients who remained in the follow-up program and one did not respond to treatment for acute bleeding control. CONCLUSION There seem to be two distinct groups of patients with gastric antral vascular ectasia: one related to immunologic disorders and other to non-immune chronic liver disease and low platelets. The endoscopic treatment using argon plasma coagulation had a high recurrence in the long-term evaluation.


World Journal of Gastroenterology | 2012

Duodenal stenting for malignant gastric outlet obstruction: Prospective study

Eduardo Guimarães Hourneaux de Moura; Flavio C. Ferreira; Spencer Cheng; Diogo Turiani Hourneaux Moura; Paulo Sakai; Bruno Zilberstain

AIM To evaluate the results of duodenal stenting for palliation of gastroduodenal malignant obstruction by using a gastric outlet obstruction score (GOOS). METHODS A prospective, non-randomized study was performed at a tertiary center between August 2005 and April 2010. Patients were eligible if they had malignant gastric outlet obstruction (GOO) and were not candidates for surgical treatment. Medical history and patient demographics were collected at baseline. Scheduled interviews were made on the day of the procedure and 15, 30, 90 and 180 d later or unscheduled as necessary. RESULTS Fifteen patients (6 male, 9 female; median age 61 years) with GOO who had undergone duodenal stenting were evaluated. Ten patients had metastasis at baseline (66.6%) and 14 were unable to accept oral intake (93.33%), including 7 patients who were using a feeding tube. Laboratory data showed biliary obstruction in eight cases (53.33%); all were submitted to biliary drainage. Two patients developed obstructive symptoms due to tumor ingrowth after 30 d and another due to tumor overgrowth after 180 d. Two cases of stent migration occurred. A good response to treatment was observed, with a mean time of approximately 1 d (19 h) until toleration of a liquid diet and slightly more than 2 d for both soft solids (51 h) and a solid food/normal diet (55 h). The mean time to first failure to maintain liquid intake (GOOS ≥ 1) was 93 d. During follow-up, the mean time to first failure to maintain the previously achieved GOOS of 2-3 (solid/semi-solid food), considered technical failure, was 71 d. On the basis of oral intake a GOOS is defined: 0 for no oral intake; 1 for liquids only; 2 for soft solids only; 3 for low-residue or full diet. CONCLUSION Enteral stenting to alleviate gastroduodenal malignant obstruction improves quality of life in patients with limited life expectancy, which can be evaluated by using a GOO scoring system.


World Journal of Gastrointestinal Endoscopy | 2011

Comparison between endoscopic sclerotherapy and band ligation for hemostasis of acute variceal bleeding

Gustavo O. Luz; Fauze Maluf-Filho; Sergio Eiji Matuguma; Fábio Yuji Hondo; Edson Ide; Jeane Martins Melo; Spencer Cheng; Paulo Sakai

AIM To compare band ligation (BL) with endoscopic sclerotherapy (SCL) in patients admitted to an emergency unit for esophageal variceal rupture. METHODS A prospective, randomized, single-center study without crossover was conducted. After endoscopic diagnosis of esophageal variceal rupture, patients were randomized into groups for SCL or BL treatment. Sclerotherapy was performed by ethanolamine oleate intravascular injection both above and below the rupture point, with a maximum volume of 20 mL. For BL patients, banding at the rupture point was attempted, followed by ligation of all variceal tissue of the distal esophagus. Primary outcomes for both groups were initial failure of bleeding control (5 d), early re-bleeding (5 d to 6 wk), and complications, including mortality. From May 2005 to May 2007, 100 patients with variceal bleeding were enrolled in the study: 50 SCL and 50 BL patients. No differences between groups were observed across gender, age, Child-Pugh status, presence of shock at admission, mean hemoglobin levels, and variceal size. RESULTS No differences were found between groups for bleeding control, early re-bleeding rates, complications, or mortality. After 6 wk, 36 (80%) SCL and 33 (77%) EBL patients were alive and free of bleeding. A statistically significant association between Child-Pugh status and mortality was found, with 16% mortality in Child A and B patients and 84% mortality in Child C patients (P<0.001). CONCLUSION Despite the limited number of patients included, our results suggest that SCL and BL are equally efficient for the control of acute variceal bleeding.


Endoscopy International Open | 2016

Stents and surgical interventions in the palliation of gastric outlet obstruction: a systematic review.

Mauricio Minata; Wanderley Marques Bernardo; Rodrigo Rocha; Flavio Morita; Julio Cesar M. Aquino; Spencer Cheng; Bruno Zilberstein; Paulo Sakai; Eduardo Guimarães Hourneaux de Moura

Background and study aims: Palliative treatment of gastric outlet obstruction can be done with surgical or endoscopic techniques. This systematic review aims to compare surgery and covered and uncovered stent treatments for gastric outlet obstruction (GOO). Patients and methods: Randomized clinical trials were identified in MEDLINE, Embase, Cochrane, LILACs, BVS, SCOPUS and CINAHL databases. Comparison of covered and uncovered stents included: technical success, clinical success, complications, obstruction, migration, bleeding, perforation, stent fracture and reintervention. The outcomes used to compare surgery and stents were technical success, complications, and reintervention. Patency rate could not be included because of lack of uniformity of the extracted data. Results: Eight studies were selected, 3 comparing surgery and stents and 5 comparing covered and uncovered stents.The meta-analysis of surgical and endoscopic stent treatment showed no difference in the technical success and overall number of complications. Stents had higher reintervention rates than surgery (RD: 0.26, 95 % CI [0.05, 0.47], NNH: 4). There is no significant difference in technical success, clinical success, complications, stent fractures, perforation, bleeding and the need for reintervention in the analyses of covered and uncovered stents. There is a higher migration rate in the covered stent therapy compared to uncovered self-expanding metallic stents (SEMS) in the palliation of malignant GOO (RD: 0.09, 95 % CI [0.04, 0.14], NNH: 11). Nevertheless, covered stents had lower obstruction rates (RD: – 0.21, 95 % CI [-0.27, – 0.15], NNT: 5). Conclusions: In the palliation of malignant GOO, covered SEMS had higher migration and lower obstruction rates when compared with uncovered stents. Surgery is associated with lower reintervention rates than stents.


Case Reports in Medicine | 2012

Endoscopic Aspects of Gastric Syphilis

Mariana Souza Varella Frazão; Thiago Guimarães Vilaça; Fred Olavo Aragão Andrade Carneiro; Kengo Toma; Carolina Eliane Reina-Forster; Elisa Baba; Spencer Cheng; Thiago Souza; Eduardo Guimarães Hourneaux de Moura; Paulo Sakai

Introduction. Considered as a rare event, gastric syphilis (GS) is reported as an organic form of involvement. Low incidence of GS emphasizes the importance of histopathological analysis. Objective. We aim to characterize GS endoscopic aspects in an immunocompetent patient. Case Report. A 23-year-old man presented with epigastric pain associated with nausea, anorexia, generalized malaise and 11 kg weight loss that started 1 month prior to his clinical consultation. Physical examination was normal except for mild abdominal tenderness in epigastrium. Endoscopy observed diminished gastric expandability and diffuse mucosal lesions, from cardia to pylorus. Gastric mucosa was thickened, friable, with nodular aspect, and associated with ulcers lesions. Gastric biopsies were performed, and histopathological analysis resulted in dense inflammatory infiltration rich in plasmocytes. Syphilis serologies were positive for VDRL and Treponema pallidum reagents. Immunohistochemical tests were positive for Treponema pallidum and CD138. The patient was treated with penicillin, leading to resolution of his clinical complaints and endoscopic findings. Conclusion. Diagnosis suspicion of GS is important in view of its nonspecific presentation. Patients with gastric symptoms that mimic neoplastic disease should be investigated thoroughly based on the fact that clinical, endoscopic, and histological findings can easily be mistaken for lymphoma or plastic linitis.


Arquivos brasileiros de cirurgia digestiva : ABCD = Brazilian archives of digestive surgery | 2016

AN INNOVATIVE EX-VIVO MODEL FOR RAPID CHANGE OF THE PAPILLA FOR TEACHING ADVANCED ENDOSCOPIC RETROGRADE CHOLANGIOPANCREATOGRAPHY PROCEDURES

Everson L. Artifon; Thaisa S. Nakadomari; Leandro Y. Kashiwagui; Emilio Belmonte; Cláudio R. Solak; Spencer Cheng; Carlos K. Furuya; José Pinhata Otoch

ABSTRACT Background: Models for endoscopic retrograde cholangiopancreatography training allow practice with an expert feedback and without risks. A method to rapidly exchange the papilla can be time saving and accelerate the learning curve. Aim: To demonstrate a newly method of rapid exchange papilla in ex-vivo models to teach retrograde cholangiopancreatography advanced procedures. Methods: A new model of ex-vivo papilla was developed in order to resemble live conditions of procedures as cannulation, papilotomy or fistula-papilotomy, papiloplasty, biliary dilatation, plastic and metallic stentings. Results: The ex-vivo model of papilla rapid exchange is feasible and imitates with realism conditions of retrograde cholangiopancreatography procedures. Conclusion: This model allows an innovative method of advanced endoscopic training.


Endoscopy International Open | 2015

Results of treatment of esophageal variceal hemorrhage with endoscopic injection of n-butyl-2-cyanoacrylate in patients with Child-Pugh class C cirrhosis

João Paulo Aguiar Ribeiro; Sergio Eiji Matuguma; Spencer Cheng; Paulo Herman; Paulo Sakai; Luiz Augusto Carneiro D'Albuquerque; Fauze Maluf-Filho

Background and study aims: The results of endoscopic treatment with elastic band ligation for esophageal variceal bleeding in patients with Child-Pugh class C cirrhosis remain poor. In comparison with treatment with elastic band ligation, we have found lower rates of rebleeding and mortality with n-butyl-2-cyanoacrylate injections. Thus, the aim of the current study was to describe our unit’s 10 years of experience with injection of n-butyl-2-cyanoacrylate to control esophageal variceal ruptures in patients with Child-Pugh class C cirrhosis. Patients and methods: A single-center, retrospective study was conducted. Sixty-three patients with Child-Pugh class C cirrhosis had been admitted to the center with an acute episode of esophageal variceal bleeding. All were treated with injection of n-butyl-2-cyanoacrylate. The patients were assigned to 1 of 2 groups according to their Child-Pugh class C cirrhosis scores: group I (score range, 10 through 13 points) and group II (score, 14 or 15 points). The 3 variables studied were rates of initial failure to control bleeding, failure to prevent rebleeding (secondary prophylaxis), and mortality. Patients in the 2 groups (group I, n = 50; group II, n = 13) had similar characteristics. Results: Bleeding was successfully controlled in almost 75 % of the patients during the first 5 days after treatment, with no significant differences observed between groups I and II. There were no significant differences between the 2 groups with respect to mortality rate for the first 5 days after treatment. Thirty-four patients (54 %) were free of bleeding at 6 weeks after treatment, with a significant difference noted between the groups: group I, 64 %, versus group II, 15.4 % (P < 0.001). The overall mortality rate was 44.4 %, with a significant difference noted between the groups: group I, 34 %, versus group II, 84.6 % (P < 0.001). Conclusion: Endoscopic injection of n-butyl-2-cyanoacrylate is a valid treatment option to control esophageal variceal bleeding in patients with a Child-Pugh class C cirrhosis score in the range of 10 through 13 points.


World Journal of Gastroenterology | 2018

Papillary fistulotomy vs conventional cannulation for endoscopic biliary access: A prospective randomized trial

Carlos K. Furuya; Paulo Sakai; Fabio R. Marinho; José Pinhata Otoch; Spencer Cheng; Lívia Lemes Prudencio; Eduardo Guimarães Hourneaux de Moura; Everson Luiz de Almeida Artifon

AIM To compare the cannulation success, biochemical profile, and complications of the papillary fistulotomy technique vs catheter and guidewire standard access. METHODS From July 2010 to May 2017, patients were prospectively randomized into two groups: Cannulation with a catheter and guidewire (Group I) and papillary fistulotomy (Group II). Amylase, lipase and C-reactive protein at T0, as well as 12 h and 24 h after endoscopic retrograde cholangiopancreatography, and complications (pancreatitis, bleeding, perforation) were recorded. RESULTS We included 102 patients (66 females and 36 males, mean age 59.11 ± 18.7 years). Group I and Group II had 51 patients each. The successful cannulation rates were 76.5% and 100%, respectively (P = 0.0002). Twelve patients (23.5%) in Group I had a difficult cannulation and underwent fistulotomy, which led to successful secondary biliary access (Failure Group). The complication rate was 13.7% (2 perforations and 5 mild pancreatitis) vs 2.0% (1 patient with perforation and pancreatitis) in Groups I and II, respectively (P = 0.0597). CONCLUSION Papillary fistulotomy was more effective than guidewire cannulation, and it was associated with a lower profile of amylase and lipase. Complications were similar in both groups.


Endoscopy International Open | 2018

EUS-FNA versus ERCP for tissue diagnosis of suspect malignant biliary strictures: a prospective comparative study

Diogo Turiani Hourneaux Moura; Eduardo Guidamarães Hourneaux de Moura; Sergio Eiji Matuguma; Marcos Eduardo Lera dos Santos; Eduardo T. Moura; Felipe Iankelevich Baracat; Everson La Artifon; Spencer Cheng; Wanderley Marque Bernardo; Danielle Azevedo Chacon; Ryan Tanigawa

Background and study aims  Biliary strictures are frequently a challenging clinical scenario and the anatomopathological diagnosis is essential in the therapeutic management, whether for curative or palliative purposes. The acquisition of specimens is necessary since many benign diseases mimic biliopancreatic neoplasms. Endscopic retrograde cholangiopancreatography (ERCP) is the traditionally used method despite the low sensitivity of biliary brush cytology and forceps biopsy. On the other hand, several studies reported good accuracy rates using endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA). The aim of this prospective study was to compare, the accuracy of EUS-FNA and ERCP for tissue sampling of biliary strictures. Patients and methods  After performing the sample size calculation, 50 consecutive patients with indeterminate biliary strictures were included to undergo ERCP and EUS on the same sedation.The gold-standard was surgery or 6 months’ follow-up. Evaluation of the diagnostic indices (sensitivity, specificity, positive and negative predictive value, positive and negative likelihood ratio), concordance and adverse events among the methods were performed. Also, subtype analyses of the techniques, anatomical localization and size of the lesion were included. Results  The final diagnoses reported in 50 patients were 47 malignant, 1 suspicious and 2 benign lesions. 31 lesions were extraductal and 19 intraductal, 35 were distal and 15 proximal strictures. In the intention-to-treat analysis, the sensitivity and accuracy of EUS-FNA were superior than ERCP tissue sampling (93,8 %, 94 % vs. 60,4 %, 62 %, respectively) ( P  = 0.034), with similar adverse events. There was no concordance between the methods and combining both methods improved the sensitivity and accuracy for 97.9 % and 98 %, respectively. In the subtype analyses, the EUS-FNA was superior, with a higher accuracy than ERCP tissue sampling in evaluating extraductal lesions (100 % vs. 54.8 %, P  = 0.019) and in those larger than 1.5 cm (95.8 % vs. 61.9 %, P  = 0.031), but were similar in evaluating intraductal lesions and lesions smaller than 1.5 cm. There was no significant difference between the methods in the analyzes of proximal, distal and pancreatic lesions. Conclusion  EUS-FNA is better than ERCP with brush cytology and intraductal forceps biopsy in diagnosing malignant biliary strictures, mainly in the assessment of extraductal lesions and in those larger than 1.5 cm. Combining ERCP with tissue sampling and EUS-FNA is feasible, the techniques have similar complication rates, and the combination greatly improves diagnostic accuracy.

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Paulo Sakai

University of São Paulo

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Diogo Moura

University of São Paulo

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Eduardo Moura

University of São Paulo

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Gustavo O. Luz

University of São Paulo

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Hugo Guedes

University of São Paulo

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