The 2023 MANCTRA Acute Biliary Pancreatitis Care Bundle: A Joint Effort Between Human Knowledge and Artificial Intelligence (ChatGPT) to Optimize the Care of Patients With Acute Biliary Pancreatitis in Western Countries.

OBJECTIVE: To generate an up-to-date bundle to manage acute biliary pancreatitis using an evidence-based, artificial intelligence (AI)-assisted GRADE method. BACKGROUND: A care bundle is a set of core elements of care that are distilled from the most solid evidence-based practice guidelines and recommendations. METHODS: The research questions were addressed in this bundle following the PICO criteria. The working group summarized the effects of interventions with the strength of recommendation and quality of evidence applying the GRADE methodology. ChatGPT AI system was used to independently assess the quality of evidence of each element in the bundle, together with the strength of the recommendations. RESULTS: The 7 elements of the bundle discourage antibiotic prophylaxis in patients with acute biliary pancreatitis, support the use of a full-solid diet in patients with mild to moderately severe acute biliary pancreatitis, and recommend early enteral nutrition in patients unable to feed by mouth. The bundle states that endoscopic retrograde cholangiopancreatography should be performed within the first 48 to 72 hours of hospital admission in patients with cholangitis. Early laparoscopic cholecystectomy should be performed in patients with mild acute biliary pancreatitis. When operative intervention is needed for necrotizing pancreatitis, this should start with the endoscopic step-up approach. CONCLUSIONS: We have developed a new care bundle with 7 key elements for managing patients with acute biliary pancreatitis. This new bundle, whose scientific strength has been increased thanks to the alliance between human knowledge and AI from the new ChatGPT software, should be introduced to emergency departments, wards, and intensive care units.

Towards a tailored approach for patients with acute diverticulitis and abscess formation. The DivAbsc2023 multicentre case-control study.

BACKGROUND: This multicentre case-control study aimed to identify risk factors associated with non-operative treatment failure for patients with CT scan Hinchey Ib-IIb and WSES Ib-IIa diverticular abscesses. METHODS: This study included a cohort of adult patients experiencing their first episode of CT-diagnosed diverticular abscess, all of whom underwent initial non-operative treatment comprising either antibiotics alone or in combination with percutaneous drainage. The cohort was stratified based on the outcome of non-operative treatment, specifically identifying those who required emergency surgical intervention as cases of treatment failure. Multivariable logistic regression analysis to identify independent risk factors associated with the failure of non-operative treatment was employed. RESULTS: Failure of conservative treatment occurred for 116 patients (27.04%). CT scan Hinchey classification IIb (aOR 2.54, 95%CI 1.61;4.01, P < 0.01), tobacco smoking (aOR 2.01, 95%CI 1.24;3.25, P < 0.01), and presence of air bubbles inside the abscess (aOR 1.59, 95%CI 1.00;2.52, P = 0.04) were independent predictors of failure. In the subgroup of patients with abscesses > 5 cm, percutaneous drainage was not associated with the risk of failure or success of the non-operative treatment (aOR 2.78, 95%CI - 0.66;3.70, P = 0.23). CONCLUSIONS: Non-operative treatment is generally effective for diverticular abscesses. Tobacco smoking's role as an independent risk factor for treatment failure underscores the need for targeted behavioural interventions in diverticular disease management. IIb Hinchey diverticulitis patients, particularly young smokers, require vigilant monitoring due to increased risks of treatment failure and septic progression. Further research into the efficacy of image-guided percutaneous drainage should involve randomized, multicentre studies focussing on homogeneous patient groups.

The influence of socioeconomic inequity and guidelines compliance on clinical outcomes of patients with acute biliary pancreatitis. An international multicentric cohort study.

BACKGROUND: There is lack of data on the association between socioeconomic factors, guidelines compliance and clinical outcomes among patients with acute biliary pancreatitis (ABP). METHODS: Post-hoc analysis of the international MANCTRA-1 registry evaluating the impact of regional disparities as indicated by the Human Development Index (HDI), and guideline compliance on ABP clinical outcomes. Multivariable logistic regression models were employed to identify prognostic factors associated with mortality and readmission. RESULTS: Among 5313 individuals from 151 centres across 42 countries marked disparities in comorbid conditions, ABP severity, and medical procedure usage were observed. Patients from lower HDI countries had higher guideline non-compliance (p < 0.001) and mortality (5.0% vs. 3.2%, p = 0.019) in comparison with very high HDI countries. On adjusted analysis, ASA score (OR 1.810, p = 0.037), severe ABP (OR 2.735, p < 0.001), infected necrosis (OR 2.225, p = 0.006), organ failure (OR 4.511, p = 0.001) and guideline non-compliance (OR 2.554, p = 0.002 and OR 2.178, p = 0.015) were associated with increased mortality. HDI was a critical socio-economic factor affecting both mortality (OR 2.452, p = 0.007) and readmission (OR 1.542, p = 0.046). CONCLUSION: These data highlight the importance of collaborative research to characterise challenges and disparities in global ABP management. Less developed regions with lower HDI scores showed lower adherence to clinical guidelines and higher rates of mortality and recurrence.

ERS: A simple scoring system to predict early recurrence after surgical resection for hepatocellular carcinoma.

BACKGROUND: Surgical resection (SR) is a potentially curative treatment of hepatocellular carcinoma (HCC) hampered by high rates of recurrence. New drugs are tested in the adjuvant setting, but standardised risk stratification tools of HCC recurrence are lacking. OBJECTIVES: To develop and validate a simple scoring system to predict 2-year recurrence after SR for HCC. METHODS: 2359 treatment-naïve patients who underwent SR for HCC in 17 centres in Europe and Asia between 2004 and 2017 were divided into a development (DS; n = 1558) and validation set (VS; n = 801) by random sampling of participating centres. The Early Recurrence Score (ERS) was generated using variables associated with 2-year recurrence in the DS and validated in the VS. RESULTS: Variables associated with 2-year recurrence in the DS were (with associated points) alpha-fetoprotein (<10 ng/mL:0; 10-100: 2; >100: 3), size of largest nodule (≥40 mm: 1), multifocality (yes: 2), satellite nodules (yes: 2), vascular invasion (yes: 1) and surgical margin (positive R1: 2). The sum of points provided a score ranging from 0 to 11, allowing stratification into four levels of 2-year recurrence risk (Wolbers' C-indices 66.8% DS and 68.4% VS), with excellent calibration according to risk categories. Wolber's and Harrell's C-indices apparent values were systematically higher for ERS when compared to Early Recurrence After Surgery for Liver tumour post-operative model to predict time to early recurrence or recurrence-free survival. CONCLUSIONS: ERS is a user-friendly staging system identifying four levels of early recurrence risk after SR and a robust tool to design personalised surveillance strategies and adjuvant therapy trials.

A core set of quality performance indicators for HPB procedures: a global consensus for hepatectomy, pancreatectomy, and complex biliary surgery.

BACKGROUND: Surgery for hepatopancreaticobiliary (HPB) conditions is performed worldwide. This investigation aimed to develop a set of globally accepted procedural quality performance indicators (QPI) for HPB surgical procedures. METHODS: A systematic literature review generated a dataset of published QPI for hepatectomy, pancreatectomy, complex biliary surgery and cholecystectomy. Using a modified Delphi process, three rounds were conducted with working groups composed of self-nominating members of the International Hepatopancreaticobiliary Association (IHPBA). The final set of QPI was circulated to the full membership of the IHPBA for review. RESULTS: Seven "core" indicators were agreed for hepatectomy, pancreatectomy, and complex biliary surgery (availability of specific services on site, a specialised surgical team with at least two certified HPB surgeons, a satisfactory institutional case volume, synoptic pathology reporting, undertaking of unplanned reintervention procedures within 90 days, the incidence of post-procedure bile leak and Clavien-Dindo grade ≥III complications and 90-day post-procedural mortality). Three further procedure specific QPI were proposed for pancreatectomy, six for hepatectomy and complex biliary surgery. Nine procedure-specific QPIs were proposed for cholecystectomy. The final set of proposed indicators were reviewed and approved by 102 IHPBA members from 34 countries. CONCLUSIONS: This work presents a core set of internationally agreed QPI for HPB surgery.

Long-Term Outcomes of Perioperative Versus Neoadjuvant Chemotherapy for Resectable Colorectal Liver Metastases: An International Multicentre Propensity-Score Matched Analysis with Stratification by Contemporary Risk-Scoring.

BACKGROUND: There is still debate regarding the principal role and ideal timing of perioperative chemotherapy (CTx) for patients with upfront resectable colorectal liver metastases (CRLM). This study assesses long-term oncological outcomes in patients receiving neoadjuvant CTx only versus those receiving neoadjuvant combined with adjuvant therapy (perioperative CTx). METHODS: International multicentre retrospective analysis of patients with CRLM undergoing liver resection between 2010 and 2015. Characteristics and outcomes were compared before and after propensity score matching (PSM). Primary endpoints were long-term oncological outcomes, such as recurrence-free survival (RFS) and overall survival (OS). Furthermore, stratification by the tumour burden score (TBS) was applied. RESULTS: Of 967 patients undergoing hepatectomy, 252 were analysed, with a median follow-up of 45 months. The unmatched comparison revealed a bias towards patients with neoadjuvant CTx presenting with more high-risk patients (p = 0.045) and experiencing increased postoperative complications ≥Clavien-Dindo III (20.9% vs. 8%, p = 0.003). Multivariable analysis showed that perioperative CTx was associated with significantly improved RFS (hazard ratio [HR] 0.579, 95% confidence interval [CI] 0.420-0.800, p = 0.001) and OS (HR 0.579, 95% CI 0.403-0.834, p = 0.003). After PSM (n = 180 patients), the two groups were comparable regarding baseline characteristics. The perioperative CTx group presented with a significantly prolonged RFS (HR 0.53, 95% CI 0.37-0.76, p = 0.007) and OS (HR 0.58, 95% CI 0.38-0.87, p = 0.010) in both low and high TBS patients. CONCLUSIONS: When patients after resection of CRLM are able to tolerate additional postoperative CTx, a perioperative strategy demonstrates increased RFS and OS in comparison with neoadjuvant CTx only in both low and high-risk situations.

Evolving Trends in the Management of Acute Appendicitis During COVID-19 Waves: The ACIE Appy II Study.

BACKGROUND: In 2020, ACIE Appy study showed that COVID-19 pandemic heavily affected the management of patients with acute appendicitis (AA) worldwide, with an increased rate of non-operative management (NOM) strategies and a trend toward open surgery due to concern of virus transmission by laparoscopy and controversial recommendations on this issue. The aim of this study was to survey again the same group of surgeons to assess if any difference in management attitudes of AA had occurred in the later stages of the outbreak. METHODS: From August 15 to September 30, 2021, an online questionnaire was sent to all 709 participants of the ACIE Appy study. The questionnaire included questions on personal protective equipment (PPE), local policies and screening for SARS-CoV-2 infection, NOM, surgical approach and disease presentations in 2021. The results were compared with the results from the previous study. RESULTS: A total of 476 answers were collected (response rate 67.1%). Screening policies were significatively improved with most patients screened regardless of symptoms (89.5% vs. 37.4%) with PCR and antigenic test as the preferred test (74.1% vs. 26.3%). More patients tested positive before surgery and commercial systems were the preferred ones to filter smoke plumes during laparoscopy. Laparoscopic appendicectomy was the first option in the treatment of AA, with a declined use of NOM. CONCLUSION: Management of AA has improved in the last waves of pandemic. Increased evidence regarding SARS-COV-2 infection along with a timely healthcare systems response has been translated into tailored attitudes and a better care for patients with AA worldwide.

Development of a prediction model of pancreatic fistula after duodenopancreatectomy and soft pancreas by assessing the preoperative image.

BACKGROUND: Pancreatic consistency is one of the most widely accepted risk factors of clinically relevant postoperative pancreatic fistula (CR-POPF) after pancreatectoduodenectomy (PD). The present study aims to identify preoperative characteristics from the preoperative computed tomography (CT) associated with an increased risk. METHODS: Retrospective observational cohort study of patients who underwent PD surgery (January 2010-2019) were enrolled. All patients with available preoperative imaging were included; 103 met the inclusion criteria. Several parameters were measured on preoperative abdominal CT: retrorenal adipose tissue; abdominal perimeter; total adipose tissue, visceral and subcutaneous; skeletal muscle mass; main pancreatic duct (MPD) diameter; pancreatic thickness; remnant pancreatic volume; pancreatic attenuation (pancreas-to-spleen ratio). Primary endpoints were the association of radiological variables with soft pancreatic consistency and POPF development. All variables possibly associated with POPF and soft pancreas were subsequently included into a multivariable logistic regression model. RESULTS: Soft pancreas consistency was found in 43 patients (41.7%) and CR-POPF was higher (51.2% vs. 18%, p < 0.001). Multivariable analysis identified MPD ≤ 3 mm (OR = 7.2, 95%CI 2.3-23, p = 0.001), a remnant pancreatic volume ≥ 20 cm3 (OR = 6.4, 95%CI 2-21, p = 0.041), pancreas-to-spleen < 0.8 (OR = 3.2, 95%CI 1.2-8.4, p = 0.039), and retrorenal adipose tissue ≥ 12 cm3 (OR = 5.3, 95%CI 1.8-15.7, p = 0.013). Multivariable analysis showed MPD ≤ 3 mm (OR = 8.25, 95%CI 2.2-30.8, p = 0.002) and total adipose tissue ≥ 190 cm3 (OR = 3.2, 95%CI 1.1-9.1, p = 0.0027) were independent predictors of CR-POPF. CONCLUSION: The preoperative assessment of MPD, remnant pancreatic volume, pancreas-to-spleen ratio, total adipose tissue, and retrorenal adipose tissue are associated with soft pancreas texture and the risk of CR-POPF.

Surgery for liver metastases from primary melanoma: a systematic review and meta-analysis.

BACKGROUND: Historically , liver metastases due to melanoma have been associated with dismal prognosis. Moreover, the actual survival benefit from the treatment of melanoma liver metastases is still controversial. Hence, this study aims to evaluate the difference in surgical versus non-surgical options for melanoma liver metastases. METHODS: Four databases (PubMed, EMBASE, Scopus, and Cochrane Library) were searched from inception to July 17, 2022. Studies were included if they compared outcomes between surgical and non-surgical treatment for patients with liver metastases from resectable melanoma. Meta-analyses were performed for the outcomes of 1-year, 2-year, 3-year and 5-year OS. Sensitivity analyses were performed for outcomes with substantial statistical heterogeneity. To account for possible moderators that might contribute to statistical heterogeneity, univariate meta-regression with mixed-effects models and subgroup analyses were conducted for the outcome of 2-year OS. RESULTS: The search yielded 6610 articles; 13 studies were included in our analysis. Meta-analyses showed that survival outcomes were in favour of patients undergoing surgery as compared to non-surgery: 1-year OS (HR = 0.29, 95%CI 0.19-0.44, p < 0.00001), 2-year OS (HR = 0.19, 95%CI 0.09-0.38, p < 0.00001), 3-year OS (HR = 0.07, 95%CI 0.03-0.19, p < 0.00001) and 5-year OS (HR = 0.07, 95%CI 0.02-0.22, p < 0.00001). All included studies were of high quality. There was moderate-to-high statistical heterogeneity. Findings were robust to sensitivity analyses. Subgroup analyses and univariate meta-regression revealed neoadjuvant therapy and age as statistically significant subgroup and moderator respectively. CONCLUSIONS: This study suggests that surgical treatment of melanoma liver metastases could offer better OS outcomes compared with non-surgical treatment.

Outcomes after curative therapy for hepatocellular carcinoma in patients with non-alcoholic fatty liver disease: a meta-analysis and review of current literature.

BACKGROUND: This systematic review and meta-analysis aimed to compare the outcomes of curative therapy (resection, transplantation, ablation) for hepatocellular carcinoma (HCC) arising from non-alcoholic fatty liver disease (NAFLD) and non-NAFLD etiologies. METHODS: A systematic search of PubMed, EMBASE and Cochrane Library was conducted for studies comparing survival, peri- and post-operative outcomes. Quality assessment was performed using the Newcastle-Ottawa scale. RESULTS: Findings for 5579 patients were pooled across 9 studies and examined. Analysis demonstrated improved disease-free survival (DFS; HR 0.85, 95% CI 0.74-0.98, p = 0.03) and overall survival (OS; HR 0.87; 95% CI 0.81-0.93; p < 0.0001) in NAFLD-HCC patients undergoing liver resection as compared to non-NAFLD HCC patients. NAFLD-HCC patients undergoing all forms of curative therapy were similarly associated with improved OS (HR 0.96; 95% CI 0.86-1.06; p = 0.40) and DFS (HR 0.85; 95% CI 0.74-0.98; p = 0.03), albeit results being significant only for DFS. Only 2 studies reported higher rates of peri- and post-operative complications in patients with NAFLD-HCC. Significant inter-study heterogeneity precluded further analysis. CONCLUSION: NAFLD-HCC patients can enjoy long-term survival benefit with aggressive curative therapy. Peri- and post-operative morbidity should be mitigated with pre-operative optimization of comorbidities, and deliberately close post-operative monitoring.

Systematic review and meta-analysis of fluid therapy protocols in acute pancreatitis: type, rate and route.

BACKGROUND: Adequate fluid resuscitation is paramount in the management of acute pancreatitis (AP). The aim of this study is to assess benefits and harms of fluid therapy protocols in patients with AP. METHODS: MEDLINE, Embase, Science Citation Index and clinical trial registries were searched for randomised clinical trials published before May 2020, assessing types of fluids, routes and rates of administration. RESULTS: A total 15 trials (1073 participants) were included. Age ranged from 38 to 73 years; follow-up period ranged from 0.5 to 6 months. Ringer lactate (RL) showed a reduced number of severe adverse events (SAE) when compared to normal saline (NS) (OR 0.48; 95%CI 0.29-0.81, p = 0.006); additionally, NS showed reduced SAE (RR 0.38; 95%IC 0.27-0.54, p < 0.001) and organ failure (RR 0.30; 95%CI 0.21-0.44, p < 0.001) in comparison with hydroxyethyl starch (HES). High fluid rate fluid infusion showed increased mortality (OR 2.88; 95%CI 1.41-5.88, p = 0.004), increased number of SAE (RR 1.42; 95%CI 1.04-1.93, p = 0.030) and higher incidence of sepsis (RR 2.80; 95%CI 1.51-5.19, p = 0.001) compared to moderate fluid rate infusion. CONCLUSIONS: In patients with AP, RL should be preferred over NS and HES should not be recommended. Based on low-certainty evidence, moderate-rate fluid infusion should be preferred over high-rate infusion.

Perioperative chemotherapy versus surgery alone for resectable colorectal liver metastases: an international multicentre propensity score matched analysis on long-term outcomes according to established prognostic risk scores.

BACKGROUND: There is still uncertainty regarding the role of perioperative chemotherapy (CTx) in patients with resectable colorectal liver metastases (CRLM), especially in those with a low-risk of recurrence. METHODS: Multicentre retrospective analysis of patients with CRLM undergoing liver resection between 2010-2015. Patients were divided into two groups according to whether they received perioperative CTx or not and were compared using propensity score matching (PSM) analysis. Then, they were stratified according to prognostic risk scores, including: Clinical Risk Score (CRS), Tumour Burden Score (TBS) and Genetic And Morphological Evaluation (GAME) score. RESULTS: The study included 967 patients with a median follow-up of 68 months. After PSM analysis, patients with perioperative CTx presented prolonged overall survival (OS) in comparison with the surgery alone group (82.8 vs 52.5 months, p = 0.017). On multivariable analysis perioperative CTx was an independent predictor of increased OS (HR 0.705, 95%CI 0.705-0.516, p = 0.029). The benefits of perioperative CTx on survival were confirmed in patients with CRS and TBS scores ≤2 (p = 0.022 and p = 0.020, respectively) and in patients with a GAME score ≤1 (p = 0.006). CONCLUSION: Perioperative CTx demonstrated an increase in OS in patients with CRLM. Patients with a low-risk of recurrence seem to benefit from systemic treatment.

GLUT-1 as a predictor of worse prognosis in pancreatic adenocarcinoma: immunohistochemistry study showing the correlation between expression and survival.

BACKGROUND: Various parameters have been considered for predicting survival in pancreatic ductal adenocarcinoma. Information about western population is missing. The aim of this study is to assess the association between Glucose transporter type 1 (GLUT-1) expression and prognosis for patients with PDAC submitted for surgical resection in a European cohort. METHODS: Retrospective analysis of PDAC specimens after pancreatoduodenectomy assessing GLUT-1 expression according to intensity (weak vs strong) and extension (low if < 80% cells were stained, high if > 80%) was performed. Statistical analysis was performed using the exact Fisher test, Student t test or the Mann-Whitney U test. Survival was analysed using the Kaplan-Meier method and compared with the Log-rank test. The differences were considered significant at a two-sided p value of < 0.05. All statistical analyses were performed using SPSS® 23.0 for Windows (SPSS Inc., Chicago, IL, USA). RESULTS: Our study consisted of 39 patients of which 58.9% presented with weak and 41.1% with strong intensity. The median extension was 90%: 28.2% cases presented with a low extension and 71.8% with a high extension. No significant differences related to intensity were found. The high-extension group showed a higher percentage of T3 PDAC (92.9% vs 63.6%, p = 0.042) and LNR20 (35.7% vs 0%, p = 0.037) as well as shorter disease-free survival (17.58 vs 54.46 months; p = 0.048). CONCLUSIONS: Our findings suggest that GLUT-1 could be related to higher aggressivity in PDAC and could be used as a prognostic marker, identifying patients with a worse response to current therapies who could benefit from more aggressive treatments.

Lymph Node Ratio, Perineural Invasion and R1 Resection as Independent Prognostic Factors in Pancreatic Adenocarcinoma: A Retrospective Cohort Study.

INTRODUCTION: The prognosis of pancreatic ductal adenocarcinoma has been associated with several factors. The aim of the present study was to correlate tumor-related factors and pathological findings with disease-free survival (DFS) and overall survival (OS) in patients undergoing pancreaticoduodenectomy. MATERIAL AND METHODS: From a prospectively maintained database, we reviewed 89 pancreatic ductal adenocarcinomas in patients who underwent pancreaticoduodenectomy from 2010 to 2014. The impact of histopathologic or tumor-related data, including a lymph node ratio greater than 15% (LNR15), on survival was analyzed. RESULTS: Univariate analysis of DFS and OS showed that vascular resection, pT, pN, LNR15, microvascular, lymphatic, and perineural invasion, and R1 resection influenced survival. Only LNR15, perineural invasion and R1 resection were independent predictors for both DFS (HR 6.39, p = 0.011; HR 8.53, p = 0.003; HR 9.68, p = 0.002, respectively) and OS (HR 4.21, p = 0.039; HR 5.41, p = 0.020; HR 4.41, p = 0.036, respectively). CONCLUSIONS: This study demonstrates that LNR15, perineural invasion and R1 resection are independently associated with DFS and OS.

Does the Artery-first Approach Improve the Rate of R0 Resection in Pancreatoduodenectomy?: A Multicenter, Randomized, Controlled Trial.

OBJECTIVE: To compare the rates of R0 resection in pancreatoduodenectomy (PD) for pancreatic and periampullary malignant tumors by means of standard (ST-PD) versus artery-first approach (AFA-PD). BACKGROUND: Standardized histological examination of PD specimens has shown that most pancreatic resections thought to be R0 resections are R1. "Artery-first approach" is a surgical technique characterized by meticulous dissection of arterial planes and clearing of retropancreatic tissue in an attempt to achieve a higher rate of R0. To date, studies comparing AFA-PD versus ST-PD are retrospective cohort or case-control studies. METHODS: A multicenter, randomized, controlled trial was conducted in 10 University Hospitals (NCT02803814, ClinicalTrials.gov). Eligible patients were those who presented with pancreatic head adenocarcinoma and periampullary tumors (ampulloma, distal cholangiocarcinoma, duodenal adenocarcinoma). Assignment to each group (ST-PD or AFA-PD) was randomized by blocks and stratified by centers. The primary end-point was the rate of tumor-free resection margins (R0); secondary end-points were postoperative complications and mortality. RESULTS: One hundred seventy-nine patients were assessed for eligibility and 176 randomized. After exclusions, the final analysis included 75 ST-PD and 78 AFA-PD. R0 resection rates were 77.3% (95% CI: 68.4-87.4) with ST-PD and 67.9% (95% CI: 58.3-79.1) with AFA-PD, P=0.194. There were no significant differences in postoperative complication rates, overall 73.3% versus 67.9%, and perioperative mortality 4% versus 6.4%. CONCLUSIONS: Despite theoretical oncological advantages associated with AFA-PD and evidence coming from low-level studies, this multicenter, randomized, controlled trial has found no difference neither in R0 resection rates nor in postoperative complications in patients undergoing ST-PD versus AFA-PD for pancreatic head adenocarcinoma and other periampullary tumors.

Transabdominal ultrasound and endoscopic ultrasound for diagnosis of gallbladder polyps.

BACKGROUND: Approximately 0.6% to 4% of cholecystectomies are performed because of gallbladder polyps. The decision to perform cholecystectomy is based on presence of gallbladder polyp(s) on transabdominal ultrasound (TAUS) or endoscopic ultrasound (EUS), or both. These polyps are currently considered for surgery if they grow more than 1 cm. However, non-neoplastic polyps (pseudo polyps) do not need surgery, even when they are larger than 1 cm. True polyps are neoplastic, either benign (adenomas) or (pre)malignant (dysplastic polyps/carcinomas). True polyps need surgery, especially if they are premalignant or malignant. There has been no systematic review and meta-analysis on the accuracy of TAUS and EUS in the diagnosis of gallbladder polyps, true gallbladder polyps, and (pre)malignant polyps. OBJECTIVES: To summarise and compare the accuracy of transabdominal ultrasound (TAUS) and endoscopic ultrasound (EUS) for the detection of gallbladder polyps, for differentiating between true and pseudo gallbladder polyps, and for differentiating between dysplastic polyps/carcinomas and adenomas/pseudo polyps of the gallbladder in adults. SEARCH METHODS: We searched the Cochrane Library, MEDLINE, Embase, Science Citation Index Expanded, and trial registrations (last date of search 09 July 2018). We had no restrictions regarding language, publication status, or prospective or retrospective nature of the studies. SELECTION CRITERIA: Studies reporting on the diagnostic accuracy data (true positive, false positive, false negative and true negative) of the index test (TAUS or EUS or both) for detection of gallbladder polyps, differentiation between true and pseudo polyps, or differentiation between dysplastic polyps/carcinomas and adenomas/pseudo polyps. We only accepted histopathology after cholecystectomy as the reference standard, except for studies on diagnosis of gallbladder polyp. For the latter studies, we also accepted repeated imaging up to six months by TAUS or EUS as the reference standard. DATA COLLECTION AND ANALYSIS: Two authors independently screened abstracts, selected studies for inclusion, and collected data from each study. The quality of the studies was evaluated using the QUADAS-2 tool. The bivariate random-effects model was used to obtain summary estimates of sensitivity and specificity, to compare diagnostic performance of the index tests, and to assess heterogeneity. MAIN RESULTS: A total of 16 studies were included. All studies reported on TAUS and EUS as separate tests and not as a combination of tests. All studies were at high or unclear risk of bias, ten studies had high applicability concerns in participant selection (because of inappropriate participant exclusions) or reference standards (because of lack of follow-up for non-operated polyps), and three studies had unclear applicability concerns in participant selection (because of high prevalence of gallbladder polyps) or index tests (because of lack of details on ultrasound equipment and performance). A meta-analysis directly comparing results of TAUS and EUS in the same population could not be performed because only limited studies executed both tests in the same participants. Therefore, the results below were obtained only from indirect test comparisons. There was significant heterogeneity amongst all comparisons (target conditions) on TAUS and amongst studies on EUS for differentiating true and pseudo polyps.Detection of gallbladder polyps: Six studies (16,260 participants) used TAUS. We found no studies on EUS. The summary sensitivity and specificity of TAUS for the detection of gallbladder polyps was 0.84 (95% CI 0.59 to 0.95) and 0.96 (95% CI 0.92 to 0.98), respectively. In a cohort of 1000 people, with a 6.4% prevalence of gallbladder polyps, this would result in 37 overdiagnosed and seven missed gallbladder polyps.Differentiation between true polyp and pseudo gallbladder polyp: Six studies (1078 participants) used TAUS; the summary sensitivity was 0.68 (95% CI 0.44 to 0.85) and the summary specificity was 0.79 (95% CI 0.57 to 0.91). Three studies (209 participants) used EUS; the summary sensitivity was 0.85 (95% CI 0.46 to 0.97) and the summary specificity was 0.90 (95% CI 0.78 to 0.96). In a cohort of 1000 participants with gallbladder polyps, with 10% having true polyps, this would result in 189 overdiagnosed and 32 missed true polyps by TAUS, and 90 overdiagnosed and 15 missed true polyps by EUS. There was no evidence of a difference between the diagnostic accuracy of TAUS and EUS (relative sensitivity 1.06, P = 0.70, relative specificity 1.15, P = 0.12).Differentiation between dysplastic polyps/carcinomas and adenomas/pseudo polyps of the gallbladder: Four studies (1,009 participants) used TAUS; the summary sensitivity was 0.79 (95% CI 0.62 to 0.90) and the summary specificity was 0.89 (95% CI 0.68 to 0.97). Three studies (351 participants) used EUS; the summary sensitivity was 0.86 (95% CI 0.76 to 0.92) and the summary specificity was 0.92 (95% CI 0.85 to 0.95). In a cohort of 1000 participants with gallbladder polyps, with 5% having a dysplastic polyp/carcinoma, this would result in 105 overdiagnosed and 11 missed dysplastic polyps/carcinomas by TAUS and 76 overdiagnosed and seven missed dysplastic polyps/carcinomas by EUS. There was no evidence of a difference between the diagnostic accuracy of TAUS and EUS (log likelihood test P = 0.74). AUTHORS' CONCLUSIONS: Although TAUS seems quite good at discriminating between gallbladder polyps and no polyps, it is less accurate in detecting whether the polyp is a true or pseudo polyp and dysplastic polyp/carcinoma or adenoma/pseudo polyp. In practice, this would lead to both unnecessary surgeries for pseudo polyps and missed cases of true polyps, dysplastic polyps, and carcinomas. There was insufficient evidence that EUS is better compared to TAUS in differentiating between true and pseudo polyps and between dysplastic polyps/carcinomas and adenomas/pseudo polyps. The conclusions are based on heterogeneous studies with unclear criteria for diagnosis of the target conditions and studies at high or unclear risk of bias. Therefore, results should be interpreted with caution. Further studies of high methodological quality, with clearly stated criteria for diagnosis of gallbladder polyps, true polyps, and dysplastic polyps/carcinomas are needed to accurately determine diagnostic accuracy of EUS and TAUS.