Núria Peláez

Nanofluidic Digital PCR for KRAS Mutation Detection and Quantification in Gastrointestinal Cancer

BACKGROUND Concomitant quantification of multiple mutant KRAS (v-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog) alleles may provide information in addition to that provided by standard mutation-detection procedures. We assessed the feasibility of a nanofluidic digital PCR array platform to detect and quantify KRAS mutations simultaneously in clinically relevant samples. METHODS We assessed 2 groups of patients (colorectal and pancreatic disease): Group 1 consisted of 27 patients with colorectal carcinomas, 14 patients with adenomas, and 5 control individuals; group 2 consisted of 42 patients with pancreatic carcinoma, 4 with adenocarcinomas of the ampulla, and 6 with chronic pancreatitis). Digital PCR was performed with the Digital Array Chip (Fluidigm). RESULTS Nanofluidic digital PCR detected mutant alleles at 0.05% to 0.1%, depending on the variant analyzed. For the colorectal disease group, conventional PCR detected 9 (64%) of 14 adenomas that were positive for KRAS mutants, whereas digital PCR increased this number to 11 (79%) of 14. Sixteen (59%) of 27 carcinomas showed KRAS mutation with conventional PCR. Two additional cases were detected with digital PCR. In 5 cases (3 adenomas, 2 carcinomas), the total number of mutant alleles changed. For the pancreatic disease group, digital PCR increased the number of positive cases from 26 to 34 (81%) and identified ≥ 2 mutant alleles in 25 cases, compared with conventional PCR, which identified multiple KRAS mutant alleles in only 12 cases. A good correlation was observed between results obtained with tumor biopsies and those obtained with pancreatic juice. CONCLUSIONS Digital PCR provides a robust, quantitative measure of the proportion of KRAS mutant alleles in routinely obtained samples. It also allows a better classification of tumors, with potential clinical relevance.

Factors influencing mortality in patients undergoing surgery for acute pancreatitis: importance of peripancreatic tissue and fluid infection.

Objectives The aims of present study were to analyze the mortality risk factors in patients who had surgery for acute pancreatitis and to assess the importance of culturing peripancreatic tissue or fluid infection to ascertain the infection status. Methods Surgery was indicated both in patients with infected severe acute pancreatitis and in those with sterile pancreatitis with an unfavorable course. During surgery, cultures were taken of tissues (pancreatic necrosis and peripancreatic fat), intra-abdominal fluid, and bile. Results Of 107 patients operated on, fluid culture was analyzed in 94 patients, pancreatic necrosis in 61 patients, peripancreatic fat in 39 patients, and bile in 38 patients. Sterile pancreatitis with sterile ascites was found in 17 patients, sterile pancreatitis with infected ascites in 22, and pancreatic tissue infection in 60. Multivariate analysis demonstrated that sterile tissue cultures, age over 65 years, and fewer than 12 days between the beginning of pain and surgery were risk factors for mortality. Sterile pancreatitis with sterile ascites and sterile pancreatitis with infected ascites had similar postoperative mortality (41% and 50%, respectively); the group with pancreatic tissue infection had a lower mortality (20%). Conclusions Early surgery, advanced age, and sterility of tissue cultures have been demonstrated as mortality factors for acute pancreatitis. Intra-abdominal fluid may be infected in the presence of sterile necrosis.

Organ-preserving surgery for benign lesions and low-grade malignancies of the pancreatic head: A matched case-control study

PurposeTo compare the postoperative results of various preservative surgery (PS) techniques with those of two types of pancreatoduodenectomy (PD).MethodsThe subjects of this study were 65 patients treated surgically for chronic pancreatitis, or benign or borderline tumors. We defined PS as any of the following: duodenum-preserving pancreatic head resection (DPPHR), uncinatectomy (UC), and cystic tumor enucleation (EN). The two types of PD were Whipple pancreatoduodenectomy (WPD) and pylorus-preserving pancreatoduodenectomy (PPPD).ResultsBenign lesions were treated with PD in 41 patients and PS in 24 patients. Whipple pancreatoduodenectomy was performed in 17 patients, PPPD in 24, DPPHR in 20, EN in 3, and UC in 1. The main indication for surgery was chronic pancreatitis (66%). Delayed gastric emptying (DGE) was seen in 41% of patients in the PD group but none in the PS group (P = 0.04). However, there were no differences between the two groups in the incidence of pancreatic fistulas or other complications. Reoperation was required in five of the PD patients, but none of the PS patients.ConclusionSurgical techniques for preserving pancreatic tissue are effective for carefully selected patients with benign pancreatic disorders.

Aplicabilidad, seguridad y eficacia de un protocolo de tratamiento ambulatorio de la diverticulitis aguda no complicada

Resumen Introduccion El objetivo de este estudio es evaluar la aplicabilidad, la seguridad y la eficacia de un protocolo de tratamiento ambulatorio de la diverticulitis aguda no complicada. Pacientes y metodos Estudio prospectivo longitudinal. Se incluyo a todos los pacientes diagnosticados mediante tomografia computarizada abdominal de diverticulitis aguda no complicada durante un periodo de 2 anos. Se excluyo a los pacientes que no toleraban la ingesta oral, que presentaban comorbilidades importantes o que no disponian de un entorno familiar adecuado. El tratamiento ambulatorio consistio en antibioticos por via oral durante 1 semana (amoxicilina-clavulanico 1 g/8 h o ciprofloxacino 500 mg/12 h y metronidazol 500 mg/8 h en pacientes con alergia a la penicilina). Ademas se les indico una dieta liquida durante los primeros 2 dias y paracetamol 1 g/8 h por via oral. Resultados Se diagnostico a 53 pacientes con diverticulitis aguda no complicada. Trece pacientes presentaban algun criterio de exclusion, por lo que se inicio el tratamiento ambulatorio en 40 pacientes. Tan solo 2 pacientes (5%) precisaron ingreso hospitalario despues de haber iniciado el tratamiento domiciliario, en un caso por persistencia del dolor y en otro por vomitos. En ambos casos, el tratamiento antibiotico intravenoso resolvio el proceso inflamatorio. En los 38 pacientes restantes (95%) se completo el tratamiento de forma satisfactoria y sin complicaciones. Conclusiones El tratamiento ambulatorio de la diverticulitis aguda no complicada no solo es eficaz y seguro, sino tambien aplicable en la mayoria de los pacientes, siempre que toleren la ingesta oral y dispongan de un entorno familiar adecuado.

[Surgical treatment of pancreatic adenocarcinoma by cephalic duodenopancreatectomy (Part 1). Post-surgical complications in 204 cases in a reference hospital].

Abstract Introduction Cephalic duodenopancreatectomy (CDP) is the treatment of choice in cancer of the head of the pancreas. However, it continues to have a high post-surgical morbidity and mortality. The aim of this article is to define variables that influence post-surgical morbidity and mortality after cephalic duodenopancreatectomy due to pancreatic adenocarcinoma (PA) cancer of the head of the pancreas (CHP). Material and methods The variables were prospectively collected form patients operated on between 1991 and 2007, in order to investigate the factors of higher morbidity. Results A total of 204 patients had been intervened due to PA, of whom 57 were older than 70 years. Of these patients, 119 had a CDP, 11 extended lymphadectomy, 66 with pyloric conservation, and 8 with extension to total pancreatectomy due to involvement of the section margin. Portal or mesenteric vein resection was included in 35 cases. Post-surgical complications were detected in 45% of cases, the most frequent being: slow gastric emptying (20%), surgical wound infection (17%), pancreatic fistula (10%), and serious medical complications (8%). Further surgery was required in 13%, and the over post-surgical mortality was 7%. A patient age greater than 70 years, post-surgical haemoperitoneum, gastroenteric dehiscence, and the presence of medical complications were post-surgical mortality risk factors in the multivariate analysis. Pancreatic fistula was not a factor associated with post-surgical mortality. Conclusions Cephalic duodenopancreatectomy is a safe technique but with a considerable morbidity. Patients over 70 years of age must be carefully selected before considering surgery. Serious medical complications must be treated aggressively to avoid an unfavourable progression.

EUS-guided methylene blue cholangiopancreatography for benign biliopancreatic diseases after failed ERCP

BACKGROUND AND AIMS When ERCP fails, EUS-guided interventional techniques may be an alternative. The aim of this study was to evaluate the general outcomes and safety of EUS-guided methylene blue cholangiopancreatography in patients with failed ERCP in benign biliopancreatic diseases. METHODS Patients with benign biliopancreatic diseases and failed ERCP were included. EUS-guided cholangiopancreatography plus injection of methylene blue was performed, and then ERCP using coloring agent flow as an indicator of papilla orifice was performed. Procedures were prospectively collected in this observational, single-center study. Technical success, clinical success, and adverse events were analyzed retrospectively. RESULTS Eleven patients were included (10 choledocholithiasis, 1 pancreatic stricture). The main reason for failed ERCP was an unidentifiable papilla. EUS-guided ductal access with cholangiopancreatography and papilla orifice identification was obtained in all cases. Technical success and clinical success rates of 91% were achieved, with successful biliopancreatic drainage in 10 patients. Adverse events included 1 peripancreatic abscess attributed to a precut, which was successfully treated. No adverse events were related to the first EUS-guided stage. CONCLUSION EUS-guided cholangiopancreatography with methylene blue injection seems to be a feasible and helpful technique for treatment in patients with benign biliopancreatic diseases with previous failed ERCP because of an undetectable papilla.

Double endosonography-guided transgastric and transduodenal drainage of infected pancreatic-fluid collections using metallic stents

A 34-year-old male was referred to our hospital for drainage of symptomatic pancreatic fluid collections (PFCs) secondary to an acute pancreatitis. He was affected by gastro-duodenal and biliary obstruction. CT scan images revealed 1 perigastric pseudocyst (well-defined wall, without necrosis content, 70 x 120 mm) and 1 periduodenal walled-off pancreatic necrosis (WOPN) (thickened wall, partially liquefied collection containing solid content, 80 x 90 mm). Both PFC were accessed under endoscopic ultrasound (EUS)-guidance with a 6 Fr-cystotom and dilation tract using a 10 mm balloon (Fig. 1). First, the pseudocyst was drained transgastrically with a fully covered SEMS with bilateral anchor Double endosonography-guided transgastric and transduodenal drainage of infected pancreatic-fluid collections using metallic stents

Fluoroscopy-assisted vs fluoroless endoscopic ultrasound-guided transmural drainage of pancreatic fluid collections: A comparative study

INTRODUCTION The need for fluoroscopy guidance in patients undergoing endoscopic ultrasound-guided transmural drainage (EUS-TMD) of peripancreatic fluid collections (PFCs) remains unclear. AIMS The aim of this study was to compare general outcomes of EUS-TMD of PFCs under fluoroscopy (F) vs fluoroless (FL). METHODS This is a comparative study with a retrospective analysis of a prospective and consecutive inclusion database at a tertiary centre, from 2009 to 2015. All patients were symptomatic pseudocyst (PSC) and walled-off pancreatic necrosis (WON). Two groups were assigned depending on availability of fluoroscopy. The groups were heterogeneous in terms of their demographic characteristics, PFCs and procedure. The main outcome measures included technical and clinical success, incidences, adverse events (AEs), and follow-up. RESULTS Fifty EUS-TMD of PFCs from 86 EUS-guided drainages were included during the study period. Group F included 26 procedures, PSC 69.2%, WON 30.8%, metal stents 61.5% (46.1% lumen-apposing stent) and plastic stents 38.5%. Group FL included 24 procedures, PSC 37.5%, WON 62.5%, and metal stents 95.8% (lumen-apposing stents). Technical success was 100% in both groups, and clinical success was similar (F 88.5%, FL 87.5%). Technical incidences and intra-procedure AEs were only described in group F (7.6% and 11.5%, respectively) and none in group FL. Procedure time was less in group FL (8min, p=0.0341). CONCLUSIONS Fluoroless in the EUS-TMD of PFCs does not involve more technical incidences or intra-procedure AEs. Technical and clinical success was similar in the two groups.

Es la duodenopancreatectomía cefálica una intervención segura en el paciente cirrótico

INTRODUCTION Pancreaticoduodenectomy (PD) is usually contraindicated in chronic liver disease. The objective of the present study was to analyze PD results in cirrhotic patients, and compare them with non-cirrhotic ones. METHODS Between 1994 and 2014 we prospectively collected all patients with a PD for periampullar neoplasms in Hospital Universitari de Bellvitge. We registered preoperative, intraoperative and postoperative variables. We defined patients undergoing PD with liver cirrhosis as the study group (CH group), and those without liver cirrhosis as the control group (NCH group). A case/control study was performed (1/2). RESULTS We registered 15 patients in the CH group, all with good liver function (Child A), and included 30 patients in NCH group. The causes of hepatopathy were HCV (60%) and alcoholism (40%). For the 3 moments studied, the CH group had a lower blood platelet count and a higher prothrombin ratio, compared with NCH group. Postoperative morbidity was 60% and mean postoperative stay was 25±19 days, with no differences in terms of complications between CH group and NCG group (73% vs. 53%, P=.1). Presence of ascites was higher in the CH group compared with NCH group (28 vs. 0%, P<.001). There were no differences in terms of hemorrhage or pancreatic fístula. Four patients of the CH group and 2 patients of the NCH group were reoperated on (26.7 vs. 6.7%, P=.1). There was no postoperative mortality. CONCLUSIONS PD is a safe procedure in cirrhotic patients with good liver function although it presents high morbidity.

Technical options for outflow reconstruction in domino liver transplantation: A single European center experience

Venous outflow is critical to the success of liver transplantation (LT). In domino liver transplantation (DLT), the venous cuffs should be shared between the donor and the recipient, and the length can be compromised. The aim of this study was to describe and compare the technical options for outflow reconstruction used at our institution. This was a retrospective analysis of 39 consecutive DLT recipients between January 1997 and May 2013. Twenty‐seven men and 12 women (mean age, 61.8 ± 4.3 years) underwent LT and consented to receive a liver from a donor with familial amyloid polyneuropathy (FAP). The main indications were hepatocellular carcinoma and hepatitis C virus cirrhosis. All recipients underwent transplantation by a piggyback technique. Liver procurement in the FAP donors was performed with the classic technique in 22 patients and with the piggyback technique in the last 17. In these latter cases, for vascular outflow reconstruction, a cadaveric venous graft was interposed between the hepatic vein (HV) stump of the FAP liver and the recipient HV in 11 cases (28%). Since 2011, we have employed arterial grafts to be interposed between the vessels stumps: a tailored arterial graft in 5 patients and an aortic graft in 1 case. There was no postoperative mortality. Arterial and portal complications presented in 2 (5.1) and 4 patients (10.3), respectively. Postoperative outflow complications (post‐LT subacute Budd‐Chiari syndrome) occurred in 4 patients, and all of them had received a venous interposed graft for reconstruction. The incidence of outflow complications tended to be higher among patients with venous grafts than those with arterial graft interposition. Overall patient survival at 1, 3, 5, and 10 years was 97%, 79%, respectively. Arterial grafts constitute a feasible and safe option for vascular outflow reconstruction in DLT because they are associated with a relatively low incidence of complications. The recently proposed Bellvitge arterial graft technique should be added to the current range of available surgical modalities. Liver Transpl 21:1051‐1055, 2015.