The Challenges of Implementing Artificial Intelligence into Surgical Practice.

BACKGROUND: Artificial intelligence is touted as the future of medicine. Classical algorithms for the detection of common bile duct stones (CBD) have had poor clinical uptake due to low accuracy. This study explores the challenges of developing and implementing a machine-learning model for the prediction of CBD stones in patients presenting with acute biliary disease (ABD). METHODS: All patients presenting acutely to Christchurch Hospital over a two-year period with ABD were retrospectively identified. Clinical data points including lab test results, demographics and ethnicity were recorded. Several statistical techniques were utilised to develop a machine-learning model. Issues with data collection, quality, interpretation and barriers to implementation were identified and highlighted. RESULTS: Issues with patient identification, coding accuracy, and implementation were encountered. In total, 1315 patients met inclusion criteria. Incorrect international classification of disease 10 (ICD-10) coding was noted in 36% (137/382) of patients recorded as having CBD stones. Patients with CBD stones were significantly older and had higher aspartate aminotransferase (AST), alanine aminotransferase (ALT), bilirubin and gamma-glutamyl transferase (GGT) levels (p < 0.001). The no information rate was 81% (1070/1315 patients). The optimum model developed was the gradient boosted model with a PPV of 67%, NPV of 87%, sensitivity of 37% and a specificity of 96% for common bile duct stones. CONCLUSION: This paper highlights the utility of machine learning in predicting CBD stones. Accuracy is limited by current data and issues do exist around both the ethics and practicality of implementation. Regardless, machine learning represents a promising new paradigm for surgical practice.

Possible involvement of interleukin-18 in the pathology of hepatobiliary adverse effects related to treatment with ceritinib.

BACKGROUND: Ceritinib demonstrated a statistically significant effect on the progression-free survival versus chemotherapy in patients with advanced anaplastic lymphoma kinase (ALK) rearrangement in non-small cell lung cancer (NSCLC) as the first therapy or after previous treatment with crizotinib and one or two prior chemotherapy regimens in global phase 3 studies. However, some serious adverse effects related to ceritinib therapy were reported across these clinical studies. Among them, a grade 3 and 4 increase in hepatobiliary enzymes was one of the common adverse events related to treatment with ceritinib. However, the pathology remains unclear. Previously, increased Interleukin (IL)-18 was observed in both biliary duct disease and liver disease. Therefore, we hypothesized that IL-18 is involved in the pathology of hepatobiliary adverse effects related to treatment with ceritinib and evaluated the serum IL-18. CASE PRESENTATION: The patient was a 53-year-old Japanese woman that we previously reported as having severe hepatobiliary adverse effects related to ceritinib therapy. Laboratory data, CT and MRI were obtained at each time point. IL-18 was evaluated by ELISA method at each time point. Immunochemical staining of liver tissue was performed as a standard protocol using antibodies against IL-18. Our records showed that the levels of serum IL-18 increased from the early stage of hepatobiliary adverse effects related to the treatment with ceritinib and were became worse with an increase in hepatobiliary enzymes and the progression of imaging abnormalities in the bile duct. Furthermore, IL-18 positive cells were detected in the inflammatory sites around the interlobular bile duct of the liver tissue. CONCLUSION: Our case report shows that the increase of serum IL-18 had a positive correlation with the progression of severe hepatobiliary adverse effects related to treatment with ceritinib and the involvement of IL-18 in the hepatobiliary inflammation by pathological evaluation. These results suggest that IL-18 could be a useful surrogate marker for the hepatobiliary toxicity of ceritinib. However, this is only one case report and further prospective observations will complement our data in the future.

Potential Prediction of Acute Biliary Pancreatitis Outcome on Admission.

OBJECTIVES: This pilot study aimed to determine the feasibility of serum values of osteonectin, adiponectin, transforming growth factor beta 1, and neurotensin being used in clinical practice to predict the severity of acute pancreatitis. METHODS: Blood samples were collected from 45 consecutive newly diagnosed acute pancreatitis patients and 30 matched healthy controls. The 2 groups were matched according to age, sex, weight, height, diabetes, smoking, and alcohol consumption. The aforementioned markers were measured using enzyme-linked immunosorbent assay kits. RESULTS: Characteristics of acute pancreatitis patients and healthy controls were comparable. Osteonectin values differed significantly (P < 0.0001). Median/lower quartile/upper quartile of osteonectin levels for acute pancreatitis patients and healthy controls were 263.5/110.3/490.36 and 63.2/46.1/87.2 ng/mL, respectively. Two patients died, 1 patient underwent necrosectomy, and 4 patients had a prolonged intensive care unit/hospital stay. Acute Physiology and Chronic Health Evaluation II and Systemic Inflammatory Response Syndrome scores neither predicted serum values of any of the measured substances nor the clinical outcome (need for intervention, prolonged intensive care unit/hospital stay and mortality). Osteonectin was the only independent predictor for clinical outcome (P = 0.007). CONCLUSIONS: Serum osteonectin strongly discriminates healthy individuals from acute pancreatitis patients. Serum osteonectin shows promise in the prediction of the clinical outcome.

Primary Epidermoid Cyst of Biliary Duct Presenting as Choledochal Cyst.

Choledochal cyst is a cystic dilation of the biliary tree that can increase the risk of malignancy in bile ducts and the gallbladder. These are usually lined by bile duct epithelium, which may undergo intestinal and squamous metaplasia. This is the first report of clinically diagnosed type II choledochal cyst that is entirely lined by metaplastic stratified squamous epithelium, unlike most other cysts, which are histologically lined by bile duct epithelium. This observation can potentially explain the underlying pathogenic mechanism of rare reports of squamous cell carcinomas arising in bile duct systems.

Predicting Success in Percutaneous Transhepatic Biliary Drainage.

PURPOSE: To develop a model to predict successful bilirubin decrease following percutaneous biliary drain placement. METHODS: A total of 257 patients who were identified having undergone percutaneous transhepatic biliary drain placement (PTBD) at our institution between 2002 and 2013 had their medical records and imaging reviewed. Of those, 190 of these patients met criteria and were used in the analysis. A regression model was performed on logarithm-transformed collected variables to predict post-drainage logarithmic transformed total bilirubin levels. A stepwise variable selection method based on Schwarz Bayesian Information Criterion was used to select the most closely associated variables. The model was validated with a Monte Carlo simulation. A short program was developed to calculate the point estimate using the model developed and compared to actual values. RESULTS: The variables that best predicted bilirubin reduction were initial Tbl (PrTbl), INR and ALT. The selected model had a root mean squared error of 0.8. The model had a negative predictive value (PoTbl is below 2 mg/dL) of 83%. CONCLUSIONS: PTBD may not achieve decreasing bilirubin in patients with a malignant obstruction. This is an initial model that can help determine which patients may not benefit from PTBD placement. With more patients, the model's validity can be increased and provide useful clinical determinant to aide patient care.

Stereotactic body radiotherapy for pediatric hepatocellular carcinoma with central biliary obstruction.

Here, we present the case of a pediatric patient with newly diagnosed hepatocellular carcinoma causing central biliary obstruction and persistently elevated bilirubin of 3.0-4.3 mg/dl despite placement of bilateral internal-external biliary drains. The tumor was not resectable, and the patient was not a candidate for liver transplant due to nodal disease, for chemotherapy due to hyperbilirubinemia, or for local therapies aside from stereotactic body radiotherapy (SBRT). In this report, we discuss the successful use of SBRT in the management of this patient, and its role in allowing the patient to become a candidate for additional therapies.

Clinical prediction rule to determine the need for repeat ERCP after endoscopic treatment of postsurgical bile leaks.

BACKGROUND AND AIMS: In patients who have undergone ERCP with biliary stenting for postsurgical bile leaks, the optimal method (ERCP or gastroscopy) and timing of stent removal is controversial. We developed a clinical prediction rule to identify cases in which a repeat ERCP is unnecessary. METHODS: Population-based study of all patients who underwent ERCP for management of surgically induced bile leaks between 2000 and 2012. Multivariate and binary recursive partitioning analyses were performed to generate a rule predicting the absence of biliary pathology on repeat endoscopic evaluation. RESULTS: A total of 259 patients were included. On multivariate analysis, postsurgical normal alkaline phosphatase (ALP; OR, 2.26; 95% CI, 1.03-4.99), time from surgery to first ERCP < 8 days (OR, 2.47; 95% CI, 1.15-5.31), and minor leak with no other pathology on initial ERCP (OR, 6.74; 95% CI, 1.75-25.89) were independently associated with the absence of persistent bile leak and other pathology on repeat ERCP. The derived rule included laparoscopic cholecystectomy, normal postsurgical ALP, minor leak with no other pathology on initial ERCP, and an interval from initial to repeat ERCP between 4 and 8 weeks. When all 4 criteria were met, the rule had a sensitivity of 94% (95% CI, 83%-99%) and a negative predictive value of 93% (95% CI, 81%-99%). Optimism-adjusted sensitivity and negative predictive value were 88% (95% CI, 76%-96%) and 86% (95% CI, 73%-96%), respectively. CONCLUSIONS: This clinical decision rule identifies patients who can have their biliary stents removed via gastroscopy, which may improve patient safety and healthcare utilization.

Diagnostic and prognostic roles of soluble CD22 in patients with Gram-negative bacterial sepsis.

BACKGROUND: Soluble CD22 (sCD22) is a fragment of CD22, a B cell-specific membrane protein that negatively regulates B-cell receptor signaling. To date, sCD22 has only been regarded as a tumor marker of B-cell malignancies. Its expression in infectious diseases has not yet been assessed. METHODS: Serum concentrations of sCD22, procalcitonin (PCT) and interleukin-6 (IL-6) were measured by enzyme-linked immunosorbent assays in patients with intra-abdominal Gram-negative bacterial infection. Receiver operating characteristic curve analysis was performed to evaluate the diagnostic accuracy of these biomarkers in this type of infection. The correlations between biomarkers and the Acute Physiology and Chronic Health Evaluation (APACHE) II scores were also analyzed. RESULTS: Concentrations of sCD22 were significantly elevated in patients with sepsis and the elevation is correlated with the severity of sepsis. sCD22 was also slightly elevated in patients with non-infected systemic inflammatory response syndrome or local infection. The diagnostic accuracy of sCD22 for sepsis was equivalent to that of PCT or IL-6. In addition, the correlation of sCD22 with APACHE II scores was stronger than that of PCT or IL-6. CONCLUSIONS: Serum sCD22 is a novel inflammatory mediator released during infection. This soluble biomarker plays a potential role in the diagnosis of Gram-negative bacterial sepsis, with a diagnostic accuracy as efficient as that of PCT or IL-6. Furthermore, sCD22 is more valuable to predict the outcomes in patients with sepsis than PCT or IL-6. The present study suggested that sCD22 might be potentially useful in supplementing current criteria for sepsis.

Comparative effectiveness of pyruvate kinase M2 in bile, serum carbohydrate antigen 19-9, and biliary brushings in diagnosing malignant biliary strictures.

BACKGROUND: The role of M2-PK (pyruvate kinase) in bile has not been studied in comparison with brushings and carbohydrate antigen (CA) 19-9 in the diagnosis of malignant biliary strictures. AIM: To compare the diagnostic accuracy of biliary M2-PK with cytology and serum CA 19-9 METHODS: In this prospective cross-sectional study, bile was aspirated in 74 patients (discovery and validation cohort) undergoing endoscopic retrograde cholangiopancreatography. Levels of M2-PK were measured in bile and compared to brushings for cytology and CA 19-9. RESULTS: In the discovery cohort, the median bile M2-PK levels were significantly elevated in patients with malignant biliary strictures [187.9 U/l (interquartile range (IQR) 3.5, 3626.8)] compared to those with benign biliary conditions and primary sclerosing cholangitis [0 U/l (IQR 0, 15)] (P = 0.007). A M2-PK cutoff value of 109.1 U/l distinguished malignant from benign conditions with a sensitivity and specificity of 52.9 and 94.1 %, respectively, and area under curve (AUC) of 0.77. The sensitivity of CA 19-9 and brushings in diagnosing cancer was 52.9 % and 11.1 % and specificity 94.1 and 100 %, respectively. The presence of elevated M2-PK >109.1 U/l or CA 19-9 >33 U/ml or positive brushing was 88.2 % sensitive and 88.2 % specific, AUC of 0.89 in the diagnosis of malignancy. The diagnostic accuracy was confirmed in the validation cohort. CONCLUSIONS: As a stand-alone factor, none of the markers were able to distinguish benign from malignant biliary strictures with a high sensitivity. However, a combination was highly sensitive in diagnosing malignant biliary strictures.

Characterization of acute biliary hyperplasia in Fisher 344 rats administered the indole-3-carbinol analog, NSC-743380.

NSC-743380 (1-[(3-chlorophenyl)-methyl]-1H-indole-3-carbinol) is in early stages of development as an anticancer agent. Two metabolites reflect sequential conversion of the carbinol functionality to a carboxaldehyde and the major metabolite, 1-[(3-chlorophenyl)-methyl]-1H-indole-3-carboxylic acid. In an exploratory toxicity study in rats, NSC-743380 induced elevations in liver-associated serum enzymes and biliary hyperplasia. Biliary hyperplasia was observed 2 days after dosing orally for 2 consecutive days at 100mg/kg/day. Notably, hepatotoxicity and biliary hyperplasia were observed after oral administration of the parent compound, but not when major metabolites were administered. The toxicities of a structurally similar but pharmacologically inactive molecule and a structurally diverse molecule with a similar efficacy profile in killing cancer cells in vitro were compared to NSC-743380 to explore scaffold versus target-mediated toxicity. Following two oral doses of 100mg/kg/day given once daily on two consecutive days, the structurally unrelated active compound produced hepatic toxicity similar to NSC-743380. The structurally similar inactive compound did not, but, lower exposures were achieved. The weight of evidence implies that the hepatotoxicity associated with NSC-743380 is related to the anticancer activity of the parent molecule. Furthermore, because biliary hyperplasia represents an unmanageable and non-monitorable adverse effect in clinical settings, this model may provide an opportunity for investigators to use a short-duration study design to explore biomarkers of biliary hyperplasia.

Presumed primary and secondary hepatic copper accumulation in cats.

OBJECTIVE: To determine signalments, clinical features, clinicopathologic variables, imaging findings, treatments, and survival time of cats with presumed primary copper-associated hepatopathy (PCH) and to determine quantitative measures and histologic characteristics of the accumulation and distribution of copper in liver samples of cats with presumed PCH, extrahepatic bile duct obstruction, chronic nonsuppurative cholangitis-cholangiohepatitis, and miscellaneous other hepatobiliary disorders and liver samples of cats without hepatobiliary disease. DESIGN: Retrospective cross-sectional study. ANIMALS: 100 cats with hepatobiliary disease (PCH [n = 11], extrahepatic bile duct obstruction [14], cholangitis-cholangiohepatitis [37], and miscellaneous hepatobiliary disorders [38]) and 14 cats without hepatobiliary disease. PROCEDURES: From 1980 to 2013, cats with and without hepatobiliary disease confirmed by liver biopsy and measurement of hepatic copper concentrations were identified. Clinical, clinicopathologic, and imaging data were compared between cats with and without PCH. RESULTS: Cats with PCH were typically young (median age, 2.0 years); clinicopathologic and imaging characteristics were similar to those of cats with other liver disorders. Copper-specific staining patterns and quantification of copper in liver samples confirmed PCH (on the basis of detection of > 700 µg/g of liver sample dry weight). Six cats with PCH underwent successful treatment with chelation (penicillamine; n = 5), antioxidants (5), low doses of elemental zinc (2), and feeding of hepatic support or high-protein, low-carbohydrate diets, and other hepatic support treatments. One cat that received penicillamine developed hemolytic anemia, which resolved after discontinuation of administration. Three cats with high hepatic copper concentrations developed hepatocellular neoplasia. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that copper accumulates in livers of cats as primary and secondary processes. Long-term management of cats with PCH was possible.

Effects of warm ischemia time on biliary injury in rat liver transplantation.

AIM: To investigate the effect of different secondary warm ischemia time (SWIT) on bile duct injury in liver-transplanted rats. METHODS: Forty-eight male inbred Sprague-Dawley rats were randomly assigned into four groups: a sham-operation group and three groups with secondary biliary warm ischemia time of 0 min, 10 min and 20 min. A rat model of autologous liver transplantation under ether anesthesia was established, and six rats were killed in each group and blood samples and the median lobe of the liver were collected for assay at 6 h and 24 h after hepatic arterial reperfusion. RESULTS: With prolongation of biliary warm ischemia time, the level of vascular endothelial growth factor-A was significantly decreased, and the value at 24 h was higher than that at 6 h after hepatic arterial reperfusion, but with no significant difference. The extended biliary SWIT led to a significant increase in bile duct epithelial cell apoptosis, and a decrease in the number of blood vessels, the bile duct surrounding the blood vessels and bile duct epithelial cell proliferation in the early postoperative portal area. Pathologic examinations showed that inflammation of the rat portal area was aggravated, and biliary epithelial cell injury was significantly worsened. CONCLUSION: A prolonged biliary warm ischemia time results in aggravated injury of the bile duct and the surrounding vascular plexus in rat autologous orthotopic liver transplantation.

Portal biliopathy in patients with non-cirrhotic portal hypertension: does the type of surgery affect outcome?

OBJECTIVES: After portosystemic anastomoses for biliopathy, some patients continue to suffer biliary obstruction. The effects of splenectomy and devascularization of the abdominal oesophagus and upper stomach are unclear. The aim of the current study was to determine the features of portal biliopathy (PB) in patients with non-cirrhotic portal hypertension, and to investigate outcomes in these patients after surgical procedures. METHODS: A retrospective study of 56 patients who underwent surgery for PB during 1996-2010 was conducted. Data on presenting features, treatment received and outcomes were analysed. RESULTS: In total, 41 of these patients had extrahepatic portal venous obstruction and 15 had non-cirrhotic portal fibrosis. Forty patients underwent shunt surgery and 16 underwent splenectomy and devascularization. Median bilirubin levels fell from 1.8 mg/dl (range: 0.4-5.9 mg/dl) to 1.0 mg/dl (range: 0.3-5.4 mg/dl) after shunt surgery and from 1.9 mg/dl (range: 0.6-4.0 mg/dl) to 1.2 mg/dl (range: 0.6-5.2 mg/dl) after splenectomy-devascularization. On follow-up, five of 33 patients had persistent jaundice after successful shunt surgery. These patients had a history of multiple endoscopic stentings and three patients had demonstrated a dominant common bile duct stricture preoperatively. CONCLUSIONS: Portal biliopathy was reversed in 38 of 43 patients by either portosystemic shunting or splenectomy-devascularization. In five patients, direct biliary decompressive procedures were required because of shunt blockage or a non-reversible biliary stricture.

Prognostic relevance of circulating CK19 mRNA in advanced malignant biliary tract diseases.

AIM: To determine the role of circulating tumor cells (CTCs) in prediction of the overall survival of patients with advanced malignant biliary tract obstruction. METHODS: We investigated the prognostic value of CTCs by examining two markers, cytokeratin (CK) 19 and human telomerase reverse transcriptase (hTERT) mRNA, in 40 patients diagnosed with advanced malignant biliary tract diseases. Quantitative real-time reverse transcription polymerase chain reaction was used to detect CK19 and hTERT mRNA in the peripheral blood of these patients. Overall survival was analyzed using the Kaplan-Meier method and Cox regression modeling. RESULTS: Positive CK19 and hTERT mRNA expression was detected in 45% and 60%, respectively, of the 40 patients. Univariable analysis indicated that positive CK19 mRNA expression was significantly associated with worse overall survival (P = 0.009). Multivariable analysis determined that positive CK19 mRNA expression, patient's age and serum bilirubin were each independently associated with overall survival. CONCLUSION: CK19 mRNA expression levels in peripheral blood appear to provide a valuable marker to predict the overall survival of patients with advanced malignant biliary tract obstruction.

Plasma concentrations of angiogenesis-related molecules in patients with pancreatic cancer.

BACKGROUND: Anti-angiogenic agents are now being clinically evaluated for the treatment of pancreatic cancer and a detailed investigation of the angiogenic profile of pancreatic cancer is needed. The aim of this study was to evaluate the plasma concentrations of angiogenesis-related molecules in patients with pancreatic cancer, compared with those with other diseases. METHODS: Plasma samples obtained from 45 patients with pancreatic cancer were analyzed and compared with those from 9 patients with pancreatitis, 16 patients with benign hepatobiliary diseases and 58 patients with colorectal cancers. The plasma levels of angiogenesis-related molecules including angiopoietin-2, follistatin, granulocyte-colony stimulating factor, hepatocyte growth factor, interleukin-8, leptin, platelet-derived growth factor beta polypeptide, platelet endothelial cell adhesion molecule-1 and vascular endothelial growth factor were determined using an antibody suspension bead arrays system. RESULTS: The plasma levels of all the angiogenesis-related molecules were not increased in patients with pancreatic cancer, compared with those with pancreatitis and benign hepatobiliary diseases, whereas the levels of those with colorectal cancer were markedly increased. The plasma interleukin-8 concentration was significantly elevated in patients with distant metastases and was associated with a poor treatment outcome of chemotherapy in patients with pancreatic cancer. CONCLUSIONS: The plasma levels of angiogenesis-related molecules were not elevated in patients with pancreatic cancer, compared with those with benign diseases or colorectal cancer. The plasma interleukin-8 level may be a novel biomarker for the response to chemotherapy in patients with pancreatic cancer and warrants further prospective study.

Specific serum IgG, but not IgA, antibody against purified Opisthorchis viverrini antigen associated with hepatobiliary disease and cholangiocarcinoma.

Opisthorchiasis caused by Opisthorchis viverrini infection induces hepatobiliary disease (HBD)-associated cholangiocarcinoma (CCA) via a chronic inflammatory immune response. Here, we evaluated specific IgG and IgA antibodies against different fractions of O. viverrini antigen in residents from an endemic community in Northeast Thailand with varying hepatobiliary abnormalities. Crude somatic O. viverrini antigen was purified into three fractions (viz., P1, P2 and P3) by gel infiltration chromatography and these served as antigens for detection of fluke-specific IgG and IgA antibodies by enzyme-linked immunosorbent assay (ELISA). The results revealed fluke-specific IgG and IgA antibody levels-against these antigens from subjects with O. viverrini-positive HBD-higher than in subjects with O. viverrini-negative HBD. Interestingly, the rank of fluke-specific IgG (and not IgA) antibody levels against crude extract and P1 antigens was CCA>severe HBD>mild HBD>healthy individuals. Purified antigens reduced cross-reactivity with other parasites compared to the crude antigen. Multiple linear regression analysis showed that HBD status was significantly associated with the liver fluke-specific IgG antibody against purified antigens. These results suggest that purified O. viverrini-antigen improves serodiagnosis for the evaluation of opisthorchiasis-associated HBD, and may be useful in the screening of opisthorchiasis in subjects at risk of developing CCA.

Diagnostic validity of serum macrophage inhibitor cytokine and tissue polypeptide-specific antigen in pancreatobiliary diseases.

BACKGROUND AND AIM: Macrophage inhibitory cytokine (MIC-1) and tissue polypeptide-specific antigen (TPS) are novel markers for several inflammatory and malignant disorders, and there are no sufficient data about the utility of these antigens as serum tumor markers. We aimed at measuring the serum levels of MIC-1 and TPS in patients with benign and malignant pancreatobiliary diseases and at determining their diagnostic efficacy. PATIENTS AND METHODS: Sera collected from patients with pancreatic adenocarcinomas (56 cases), periampullary carcinomas other than pancreatic carcinomas (15 cases), benign pancreatic diseases (31 cases), benign biliary diseases (15 cases) and healthy volunteers (33 cases) were analyzed for MIC-1 and TPS and the results were compared with CA 19-9. RESULTS: Serum MIC-1 levels increased more significantly in patients with pancreatic carcinomas than in patients with benign pancreatobiliary diseases and healthy controls (p < 0.05). MIC-1 has a similar sensitivity (81%) but a lower specificity (73 vs. 97%) than CA 19-9 in patients with pancreatic carcinomas. Serum TPS was comparable among patients with malignant and benign pancreatobiliary diseases, and healthy controls. CONCLUSION: MIC-1 is a valuable tumor marker for the diagnosis of pancreatic cancer. It has a good correlation with CA 19-9. TPS has no diagnostic importance to differentiate pancreatobiliary diseases. and IAP.

Bilirubin levels predict malignancy in patients with obstructive jaundice.

BACKGROUND: Differentiating between benign and malignant causes of obstructive jaundice can be challenging, even with the advanced imaging and endoscopic techniques currently available. In patients with obstructive jaundice, the predictive accuracy of bilirubin levels at presentation was examined in order to determine whether such data could be used to differentiate between malignant and benign disease. METHODS: A total of 1,026 patients with obstructive jaundice were identified. Patients were divided into benign and malignant groups. The benign patients were subgrouped into those with choledocholithiasis and those with inflammatory strictures of the biliary tree. Bilirubin levels at presentation and other demographic data were obtained from case records. RESULTS: Area under the curve (AUC) values for bilirubin as a predictor of malignancy were highly significant for all benign presentations and for those with benign biliary strictures (AUC: 0.8 for both groups; P < 0.001). A bilirubin level > 100 µmol/l was determined to provide the optimum sensitivity and specificity for malignancy in all patients and in those without choledocholithiasis (71.9% and 86.9%, 71.9% and 88.0%, respectively). The application of a bilirubin level > 250 µmol/l achieved specificities of 97.1% and 98.0% in each subgroup of patients, respectively. CONCLUSIONS: In patients with obstructive jaundice, bilirubin levels in isolation represent an important tool for discriminating between benign and malignant underlying causes.

Feasibility of identifying pancreatic cancer based on serum metabolomics.

BACKGROUND: We postulated that the abundance of various metabolites in blood would facilitate the diagnosis of pancreatic and biliary lesions, which could potentially prevent unnecessary surgery. METHODS: Serum samples from patients with benign hepatobiliary disease (n = 43) and from patients with pancreatic cancer (n = 56) were examined by ¹H NMR spectroscopy to quantify 58 unique metabolites. Data were analyzed by "targeted profiling" followed by supervised pattern recognition and orthogonal partial least-squares discriminant analysis (O-PLS-DA) of the most significant metabolites, which enables comparison of the whole sample spectrum between groups. RESULTS: The metabolomic profile of patients with pancreatic cancer was significantly different from that of patients with benign disease (AUROC, area under the ROC curve, = 0.8372). Overt diabetes mellitus (DM) was identified as a possible confounding factor in the pancreatic cancer group. Thus, diabetics were excluded from further analysis. In this more homogeneous pancreatic cancer group, compared with benign cases, serum concentrations of glutamate and glucose were most elevated on multivariate analysis. In benign cases, creatine and glutamine were most abundant. To examine the usefulness of this test, a comparison was made to age- and gender-matched controls with benign lesions that mimic cancer, controlling also for presence of jaundice and diabetes (n = 14 per group). The metabolic profile in patients with pancreatic cancer remained distinguishable from patients with benign pancreatic lesions (AUROC = 0.8308). CONCLUSIONS: The serum metabolomic profile may be useful for distinguishing benign from malignant pancreatic lesions. IMPACT: Further studies will be required to study the effects of jaundice and diabetes. A more comprehensive metabolomic profile will be evaluated using mass spectrometry.