Meta-analysis of effect of routine enteral nutrition on postoperative outcomes after pancreatoduodenectomy.

BACKGROUND: The optimal nutritional treatment after pancreatoduodenectomy is still unclear. The aim of this meta-analysis was to investigate the impact of routine enteral nutrition following pancreatoduodenectomy on postoperative outcomes. METHODS: RCTs comparing enteral nutrition (regular oral intake with routine tube feeding) with non-enteral nutrition (regular oral intake with or without parenteral nutrition) after pancreatoduodenectomy were sought systematically in the MEDLINE, Cochrane Library and Web of Science databases. Postoperative data were extracted. Random-effects meta-analyses were performed to compare postoperative outcomes in the two arms, and pooled odds ratios (ORs) or mean differences (MDs) were calculated with 95 per cent confidence intervals. In subgroup analyses, the routes of nutrition were assessed. Percutaneous tube feeding and nasojejunal tube feeding were each compared with parenteral nutrition. RESULTS: Eight RCTs with a total of 955 patients were included. Enteral nutrition was associated with a lower incidence of infectious complications (OR 0·66, 95 per cent c.i. 0·43 to 0·99; P = 0·046) and a shorter length of hospital stay (MD -2·89 (95 per cent c.i. -4·99 to -0·80) days; P < 0·001) than non-enteral nutrition. Percutaneous tube feeding had a lower incidence of infectious complications (OR 0·47, 0·25 to 0·87; P = 0·017) and a shorter hospital stay (MD -1·56 (-2·13 to -0·98) days; P < 0·001) than parenteral nutrition (3 RCTs), whereas nasojejunal tube feeding was not associated with better postoperative outcomes (2 RCTs). CONCLUSION: As a supplement to regular oral diet, routine enteral nutrition, especially via a percutaneous enteral tube, may improve postoperative outcomes after pancreatoduodenectomy.

Meta-analysis of recurrence pattern after resection for pancreatic cancer.

BACKGROUND: Initial recurrence mapping of resected pancreatic ductal adenocarcinoma (PDAC) could help in stratifying patient subpopulations for optimal postoperative follow-up. The aim of this systematic review and meta-analysis was to investigate the initial recurrence patterns of PDAC and to correlate them with clinicopathological factors. METHODS: MEDLINE and Web of Science databases were searched systematically for studies reporting first recurrence patterns after PDAC resection. Data were extracted from the studies selected for inclusion. Pooled odds ratios (ORs) and 95 per cent confidence intervals were calculated to determine the clinicopathological factors related to the recurrence sites. The weighted average of median overall survival was calculated. RESULTS: Eighty-nine studies with 17 313 patients undergoing PDAC resection were included. The weighted median rates of initial recurrence were 20·8 per cent for locoregional sites, 26·5 per cent for liver, 11·4 per cent for lung and 13·5 per cent for peritoneal dissemination. The weighted median overall survival times were 19·8 months for locoregional recurrence, 15·0 months for liver recurrence, 30·4 months for lung recurrence and 14·1 months for peritoneal dissemination. Meta-analysis revealed that R1 (direct) resection (OR 2·21, 95 per cent c.i. 1·12 to 4·35), perineural invasion (OR 5·19, 2·79 to 9·64) and positive peritoneal lavage cytology (OR 5·29, 3·03 to 9·25) were significantly associated with peritoneal dissemination as initial recurrence site. Low grade of tumour differentiation was significantly associated with liver recurrence (OR 4·15, 1·71 to 10·07). CONCLUSION: Risk factors for recurrence patterns after surgery could be considered for specific surveillance and treatments for patients with pancreatic cancer.

ANTECEDENTES: El mapeo del patrón de recidiva inicial tras la resección de un adenocarcinoma ductal pancreático (pancreatic ductal adenocarcinoma, PDAC) podría ayudar a estratificar subpoblaciones de pacientes para un seguimiento postoperatorio óptimo. El objetivo de esta revisión sistemática con metaanálisis fue investigar los patrones de recidiva inicial de PDAC y correlacionarlos con factores clínico-patológicos. MÉTODOS: Se realizaron búsquedas sistemáticas en las bases de datos MEDLINE y Web of Science para seleccionar estudios que presentaran información sobre los patrones de recidiva inicial después de la resección del PDAC. Se extrajeron los datos de los estudios seleccionados para su inclusión en el metaanálisis. Se calcularon las razones de oportunidades agrupadas (pooled odds ratio, OR) y los i.c. del 95% para definir los factores clínico-patológicos relacionados con las localizaciones de la recidiva. Se estimó el promedio ponderado de la mediana de la supervivencia global. RESULTADOS: Se incluyeron 89 estudios con 17.313 pacientes a los que se realizó una resección por PDAC. Las tasas medias ponderadas de las localizaciones de la recidiva inicial fueron del 20,8% para la locorregional, 26,5% para las hepáticas, 11,4% para el pulmón y 13,5% para la diseminación peritoneal. La mediana ponderada de supervivencia global fue de 19,8 meses (locorregional), 15,0 meses (hígado), 30,4 meses (pulmón) y 14,1 meses (diseminación peritoneal). El metaanálisis demostró que la resección R1 (inicial) (OR 2,21, i.c. del 95% 1,12-4,35), la invasión perineural (OR 5,19; i.c. del 95% 2,79-9,64) y la positividad de la citología del lavado peritoneal (OR 5,29; i.c. del 95% 3,03-9,25) se asociaron significativamente con la diseminación peritoneal como localización de recidiva inicial. El bajo grado de diferenciación tumoral se asoció significativamente con la recidiva hepática (OR 4,15; i.c. del 95%: 1,71-10,07). CONCLUSIÓN: Se podrían tener en cuenta estos factores de riesgo de los patrones de recidiva tras la cirugía para realizar un seguimiento y tratamiento específicos en pacientes con cáncer de páncreas.

Meta-analysis of delayed gastric emptying after pylorus-preserving versus pylorus-resecting pancreatoduodenectomy.

BACKGROUND: Delayed gastric emptying (DGE) is a frequent complication after pylorus-preserving pancreatoduodenectomy. Recent studies have suggested that resection of the pylorus is associated with decreased rates of DGE. However, superiority of pylorus-resecting pancreatoduodenectomy was not shown in a recent RCT. This meta-analysis summarized evidence of the effectiveness and safety of pylorus-preserving compared with pylorus-resecting pancreatoduodenectomy. METHODS: RCTs and non-randomized studies comparing outcomes of pylorus-preserving and pylorus-resecting pancreatoduodenectomy were searched systematically in MEDLINE, Web of Science and CENTRAL. Random-effects meta-analyses were performed and the results presented as weighted odds ratios (ORs) or mean differences with their corresponding 95 per cent confidence intervals. Subgroup analyses were performed to account for interstudy heterogeneity between RCTs and non-randomized studies. RESULTS: Three RCTs and eight non-randomized studies with a total of 992 patients were included. Quantitative synthesis across all studies showed superiority for pylorus-resecting pancreatoduodenectomy regarding DGE (OR 2·71, 95 per cent c.i. 1·48 to 4·96; P = 0·001) and length of hospital stay (mean difference 3·26 (95 per cent c.i. -1·04 to 5·48) days; P = 0·004). Subgroup analyses including only RCTs showed no significant statistical differences between the two procedures regarding DGE, and for all other effectiveness and safety measures. CONCLUSION: Pylorus-resecting pancreatoduodenectomy is not superior to pylorus-preserving pancreatoduodenectomy for reducing DGE or other relevant complications.

Meta-analysis of immunonutrition in major abdominal surgery.

BACKGROUND: The objective of this study was to evaluate the potential benefits of immunonutrition in major abdominal surgery with special regard to subgroups and influence of bias. METHODS: A systematic literature search from January 1985 to July 2015 was performed in MEDLINE, Embase and CENTRAL. Only RCTs investigating immunonutrition in major abdominal surgery were included. Outcomes evaluated were mortality, overall complications, infectious complications and length of hospital stay. The influence of different domains of bias was evaluated in sensitivity analyses. Evidence was rated according to the GRADE Working Group grading of evidence. RESULTS: A total of 83 RCTs with 7116 patients were included. Mortality was not altered by immunonutrition. Taking all trials into account, immunonutrition reduced overall complications (odds ratio (OR) 0·79, 95 per cent c.i. 0·66 to 0·94; P = 0·01), infectious complications (OR 0·58, 0·51 to 0·66; P < 0·001) and shortened hospital stay (mean difference -1·79 (95 per cent c.i. -2·39 to -1·19) days; P < 0·001) compared with control groups. However, these effects vanished after excluding trials at high and unclear risk of bias. Publication bias seemed to be present for infectious complications (P = 0·002). Non-industry-funded trials reported no positive effects for overall complications (OR 1·13, 0·88 to 1·46; P = 0·34), whereas those funded by industry reported large effects (OR 0·66, 0·48 to 0·91; P = 0·01). CONCLUSION: Immunonutrition after major abdominal surgery did not seem to alter mortality (GRADE: high quality of evidence). Immunonutrition reduced overall complications, infectious complications and shortened hospital stay (GRADE: low to moderate). The existence of bias lowers confidence in the evidence (GRADE approach).

Meta-analysis of complication rates for single-loop versus dual-loop (Roux-en-Y) with isolated pancreaticojejunostomy reconstruction after pancreaticoduodenectomy.

BACKGROUND: Postoperative pancreatic fistula is one of the most important and potentially severe complications after partial pancreaticoduodenectomy. In this context, the reduction of postoperative pancreatic fistula by means of a dual-loop (Roux-en-Y) reconstruction with isolation of the pancreaticojejunostomy from biliary drainage has been evaluated in several studies. This systematic review and meta-analysis summarizes evidence of effectiveness and safety of the isolation of the pancreaticojejunostomy compared with conventional single-loop reconstruction. METHODS: Randomized clinical trials (RCTs) and controlled clinical trials (CCTs) comparing outcomes of dual-loop reconstruction with isolated pancreaticojejunostomy and single-loop reconstruction were searched according to PRISMA guidelines. Random-effects meta-analyses were performed and the results presented as weighted risk ratios or mean differences with their corresponding 95 per cent c.i. RESULTS: Of 83 trials screened for eligibility, three RCTs and four CCTs including a total of 802 patients were finally included. Quantitative synthesis showed no significant statistical difference between the two procedures regarding postoperative pancreatic fistula, delayed gastric emptying, haemorrhage, intra-abdominal fluid collection or abscess, bile leakage, wound infection, pneumonia, overall morbidity, mortality, reinterventions, reoperations, perioperative blood loss and length of hospital stay. Duration of surgery was significantly longer in patients undergoing dual-loop reconstruction. CONCLUSION: Dual-loop (Roux-en-Y) reconstruction with isolated pancreaticojejunostomy after partial pancreaticoduodenectomy is not superior to single-loop reconstruction regarding pancreatic fistula rate or other relevant outcomes. Additional superiority trials are therefore not warranted, although a high-quality trial may be justified to prove equivalence or non-inferiority.