Roongruedee Chaiteerakij

Utility of serum immunoglobulin G4 in distinguishing immunoglobulin G4-associated cholangitis from cholangiocarcinoma.

Elevated serum immunoglobulin G4 (sIgG4) is a feature of autoimmune pancreatitis (AIP) and IgG4‐associated cholangitis (IAC); a >2‐fold increase in sIgG4 is considered highly specific for these disorders. Many patients with IAC present with biliary strictures and obstructive jaundice, making cholangiocarcinoma (CCA) an important differential diagnosis. We determined the value of sIgG4 in distinguishing IAC from CCA. sIgG4 levels were measured in a test cohort of 126 CCA and 50 IAC patients. The results were confirmed in a validation cohort of 161 CCA and 47 IAC patients. Of the 126 CCA patients in the test cohort, 17 (13.5%) had elevated sIgG4 (>140 mg/dL) and four (3.2%) had a >2‐fold (>280 mg/dL) increase. Primary sclerosing cholangitis (PSC) was present in 31/126 CCA patients, of whom seven (22.6%) had elevated sIgG4 and two (6.5%) had a >2‐fold elevation. Of the 50 IAC patients, 39 (78.0%) had elevated sIgG4 and 25 (50.0%) had a >2‐fold increase. The results in the validation cohort were consistent with those of the test cohort. Conclusion: Although elevated sIgG4 levels are characteristic of IAC, some patients with CCA, particularly with PSC, have elevated sIgG4 levels, including a small percentage with a more than a 2‐fold increase in sIgG4. Therefore, sIgG4 elevation alone does not exclude the diagnosis of CCA. Depending on the prevalence of the two diagnoses, the use of a 2‐fold cutoff for sIgG4 may not reliably distinguish IAC from CCA. At a cutoff of 4 times the upper limit of normal, sIgG4 is 100% specific for IAC. (HEPATOLOGY 2011;)

Factors That Affect Risk for Hepatocellular Carcinoma and Effects of Surveillance

BACKGROUND & AIMSnThe incidence of hepatocellular carcinoma (HCC) in the United States is increasing. Surveillance may affect the stage at diagnosis and consequently the treatment options available for HCC. We evaluated risk factors for HCC, the proportion of cases detected via surveillance, tumor characteristics, treatment approaches, and overall patient survival in a referral center cohort.nnnMETHODSnThe study included all patients diagnosed with HCC at the Mayo Clinic, Rochester, Minnesota, from 2007 to 2009 (n = 460). Clinical information was retrospectively abstracted from the medical record.nnnRESULTSnHepatitis C virus (HCV, 36%), alcohol use (29%), and nonalcoholic fatty liver disease (NAFLD, 13%) were the most common risk factors for HCC. HCV was present in 56% of patients younger than 60. NAFLD was present in 19% of patients older than 60. HCC was detected during surveillance in 31% of patients. Patients with worse liver function were more likely to be on surveillance. Transarterial chemoembolization, surgical resection, and liver transplantation were the most common treatment approaches for HCC. Patients diagnosed with HCC during surveillance had less advanced disease, were more likely to be eligible for potentially curative treatments, and had increased survival times (P < .001).nnnCONCLUSIONSnAt a major US referral center, the predominant HCC etiologies were HCV, alcohol use, and NAFLD. HCCs were detected during surveillance in the minority of patients. HCCs detected during surveillance were of less advanced stage, and patients were more likely to receive treatment that prolonged their survival.

Continuation of metformin use after a diagnosis of cirrhosis significantly improves survival of patients with diabetes

The risks and benefits of metformin use in patients with cirrhosis with diabetes are debated. Although data on a protective effect of metformin against liver cancer development have been reported, metformin is frequently discontinued once cirrhosis is diagnosed because of concerns about an increased risk of adverse effects of metformin in patients with liver impairment. This study investigated whether continuation of metformin after cirrhosis diagnosis improves survival of patients with diabetes. Diabetic patients diagnosed with cirrhosis between 2000 and 2010 who were on metformin at the time of cirrhosis diagnosis were identified (n = 250). Data were retrospectively abstracted from the medical record. Survival of patients who continued versus discontinued metformin after cirrhosis diagnosis was compared using the log‐rank test. Hazard ratio (HR) and 95% confidence interval (CI) were calculated using Coxs proportional hazards analysis. Overall, 172 patients continued metformin whereas 78 discontinued metformin. Patients who continued metformin had a significantly longer median survival than those who discontinued metformin (11.8 vs. 5.6 years overall, P < 0.0001; 11.8 vs. 6.0 years for Child A patients, P = 0.006; and 7.7 vs. 3.5 years for Child B/C patients, P = 0.04, respectively). After adjusting for other variables, continuation of metformin remained an independent predictor of better survival, with an HR of 0.43 (95% CI: 0.24‐0.78; P = 0.005). No patients developed metformin‐associated lactic acidosis during follow‐up. Conclusion: Continuation of metformin after cirrhosis diagnosis reduced the risk of death by 57%. Metformin should therefore be continued in diabetic patients with cirrhosis if there is no specific contraindication. (Hepatology 2014;60:2007–2015)

Risk factors for intrahepatic cholangiocarcinoma: Association between metformin use and reduced cancer risk

The associations between diabetes, smoking, obesity, and intrahepatic cholangiocarcinoma (ICC) risk remain inconclusive. Metformin is purportedly associated with a reduced risk for various cancers. This case‐control study evaluated risk factors for ICC and explored the effects of metformin on ICC risk in a clinic/hospital‐based cohort. ICC patients observed at the Mayo Clinic (Rochester, MN) between January 2000 and May 2010 were identified. Age, sex, ethnicity, and residential area‐matched controls were selected from among Mayo Clinic Biobank participants. The associations between potential factors and ICC risk were determined. Six hundred and twelve cases and 594 controls were identified. Factors associated with increased ICC risk included biliary tract diseases (adjusted odds ratio [AOR]: 81.8; 95% confidence interval [CI]: 11.2‐598.8; P < 0.001), cirrhosis (AOR, 8.0; 95% CI: 1.8‐36.5; P = 0.007), diabetes (AOR, 3.6; 95% CI: 2.3‐5.5; P < 0.001), and smoking (AOR, 1.6; 95% CI: 1.3‐2.1; P < 0.001). Compared to diabetic patients not treated with metformin, the odds ratio (OR) for ICC for diabetic patients treated with metformin was significantly decreased (OR, 0.4; 95% CI: 0.2‐0.9; P = 0.04). Obesity and metabolic syndrome were not associated with ICC. Conclusion: This study confirmed diabetes and smoking as independent risk factors for ICC. A novel finding was that treatment with metformin was significantly associated with a 60% reduction in ICC risk in diabetic patients. (HEPATOLOGY 2013)

Update on Biomarkers of Hepatocellular Carcinoma

New biomarkers of hepatocellular carcinoma (HCC) have been identified using advanced genomic, proteomic, and metabolomics technologies. These are being developed not only for use in diagnosis of HCC, but also in prediction of patient and treatment outcomes and individualization of therapy. Some HCC biomarkers are currently used in surveillance to detect early stage HCCs and reduce mortality. Further studies are needed to determine whether the recently identified HCC biomarkers can be used in clinical practice; most are only in phase 1 or 2 studies. The diagnostic and predictive abilities of biomarkers are limited by the heterogeneous nature of HCCs; there is no perfect single biomarker of this tumor. To improve performance, combinations of biomarkers (panels), or combinations of biomarkers and clinical parameters or laboratory test results, might be required. We describe recently discovered biomarkers of HCC and discuss challenges to their development and application.

Model to estimate survival in ambulatory patients with hepatocellular carcinoma.

Survival of patients with hepatocellular carcinoma (HCC) is determined by the extent of the tumor and the underlying liver function. We aimed to develop a survival model for HCC based on objective parameters including the Model for Endstage Liver Disease (MELD) as a gauge of liver dysfunction. This analysis is based on 477 patients with HCC seen at Mayo Clinic Rochester between 1994 and 2008 (derivation cohort) and 904 patients at the Korean National Cancer Center between 2000 and 2003 (validation cohort). Multivariate proportional hazards models and corresponding risk score were created based on baseline demographic, clinical, and tumor characteristics. Internal and external validation of the model was performed. Discrimination and calibration of this new model were compared against existing models including Barcelona Clinic Liver Cancer (BCLC), Cancer of the Liver Italian Program (CLIP), and Japan Integrated Staging (JIS) scores. The majority of the patients had viral hepatitis as the underlying liver disease (100% in the derivation cohort and 85% in the validation cohort). The survival model incorporated MELD, age, number of tumor nodules, size of the largest nodule, vascular invasion, metastasis, serum albumin, and alpha‐fetoprotein. In cross‐validation, the coefficients remained largely unchanged between iterations. Observed survival in the validation cohort matched closely with what was predicted by the model. The concordance (c)‐statistic for this model (0.77) was superior to that for BCLC (0.71), CLIP (0.70), or JIS (0.70). The score was able to further classify patient survival within each stage of the BCLC classification. Conclusion: A new model to predict survival of HCC patients based on objective parameters provides refined prognostication and supplements the BCLC classification. (HEPATOLOGY 2012)

A New Clinically Based Staging System for Perihilar Cholangiocarcinoma

OBJECTIVES:Current staging systems for perihilar cholangiocarcinoma (pCCA) are inadequate, as they are based on surgical pathology and therefore not relevant to unresectable patients. Clinical trials for potential targeted therapies for pCCA are hampered by the lack of an accurate, nonoperative staging system for predicting survival. We aimed at developing a clinical staging system for pCCA, which would be of prognostic relevance for all pCCA patients and help stratify patients for clinical trials.METHODS:Clinical information at the time of pCCA diagnosis of 413 patients seen at Mayo Clinic, Rochester, MN between 2002 and 2010 was retrospectively analyzed. A survival predictive model was developed using Cox proportional hazards analysis. The performance of the staging system was compared with the current AJCC/UICC (the American Joint Committee on Cancer/the Union for International Cancer Control) 7th tumor-node-metastasis (TNM) staging system.RESULTS:Eastern Cooperative Oncology Group (ECOG) status, tumor size and number, vascular encasement, lymph node and peritoneal metastasis and CA 19-9 level were grouped into a four-tier staging system. The median survivals of stages I, II, III, and IV patients were 48.6, 21.8, 8.6, and 2.8 months, with hazard ratios (95% confidence interval) of 1.0 (reference), 1.7 (1.1–2.6), 3.1 (2.0–4.7), and 8.7 (5.2–14.5), respectively (P<0.0001). This staging system had greater concordance statistics (standard error) than the TNM staging system (0.725 (0.018) vs. 0.614 (0.017)), indicating better performance in predicting survival.CONCLUSIONS:This staging system, based on nonoperative information at the time of pCCA diagnosis, has excellent discriminatory power to classify patients into four prognostic stages. It could be useful to clinicians and for the design of clinical trials.

An Optimized Set of Fluorescence In Situ Hybridization Probes for Detection of Pancreatobiliary Tract Cancer in Cytology Brush Samples

BACKGROUND & AIMSnPancreatobiliary cancer is detected by fluorescence in situ hybridization (FISH) of pancreatobiliary brush samples with UroVysion probes, originally designed to detect bladder cancer. We designed a set of new probes to detect pancreatobiliary cancer and compared its performance with that of UroVysion and routine cytology analysis.nnnMETHODSnWe tested a set of FISH probes on tumor tissues (cholangiocarcinoma or pancreatic carcinoma) and non-tumor tissues from 29 patients. We identified 4 probes that had high specificity for tumor vs non-tumor tissues; we called this set of probes pancreatobiliary FISH. We performed a retrospective analysis of brush samples from 272 patients who underwent endoscopic retrograde cholangiopancreatography for evaluation of malignancy at the Mayo Clinic; results were available from routine cytology and FISH with UroVysion probes. Archived residual specimens were retrieved and used to evaluate the pancreatobiliary FISH probes. Cutoff values for FISH with the pancreatobiliary probes were determined using 89 samples and validated in the remaining 183 samples. Clinical and pathologic evidence of malignancy in the pancreatobiliary tract within 2 years of brush sample collection was used as the standard; samples from patients without malignancies were used as negative controls. The validation cohort included 85 patients with malignancies (46.4%) and 114 patients with primary sclerosing cholangitis (62.3%). Samples containing cells above the cutoff for polysomy (copy number gain of ≥2 probes) were classified as positive in FISH with the UroVysion and pancreatobiliary probes. Multivariable logistic regression was used to estimate associations between clinical and pathology findings and results from FISH.nnnRESULTSnThe combination of FISH probes 1q21, 7p12, 8q24, and 9p21 identified cancer cells with 93% sensitivity and 100% specificity in pancreatobiliary tissue samples and were therefore included in the pancreatobiliary probe set. In the validation cohort of brush samples, pancreatobiliary FISH identified samples from patients with malignancy with a significantly higher level of sensitivity (64.7%) than the UroVysion probes (45.9%) (P < .001) or routine cytology analysis (18.8%) (Pxa0<xa0.001), but similar specificity (92.9%, 90.8%, and 100.0%xa0respectively). Factors significantly associated with detection of carcinoma, in adjusted analyses, included detection of polysomy by pancreatobiliary FISH (P < .001), a mass by cross-sectional imaging (P < .001), cancer cells by routine cytology (overall Pxa0= .003), as well as absence of primary sclerosing cholangitis (Pxa0= .011).nnnCONCLUSIONSnWe identified a set of FISH probes that detects cancer cells in pancreatobiliary brush samples from patients with and without primary sclerosing cholangitis with higher levels of sensitivity than UroVysion probes. Cytologic brushing test results and clinical features were independently associated with detection of cancer and might be used to identify patients with pancreatobiliary cancers.

Combinations of biomarkers and Milan criteria for predicting hepatocellular carcinoma recurrence after liver transplantation.

Growing evidence suggests that pretransplant alpha‐fetoprotein (AFP) predicts outcomes of hepatocellular carcinoma (HCC) patients treated with liver transplantation. We aimed to determine whether pretransplant AFP, Lens culinaris agglutinin‐reactive alpha‐fetoprotein (AFP‐L3), and des‐gamma‐carboxyprothrombin (DCP) predicted HCC recurrence after transplantation. A retrospective cohort study of 313 HCC patients undergoing transplantation between 2000 and 2008 was conducted, and 48 (15.3%) developed recurrence during a median follow‐up of 90.8 months. The 127 patients with available serum drawn before transplantation were included; they included 86 without recurrence and 41 with recurrence. Serum was tested for AFP, AFP‐L3%, and DCP in a blinded fashion with the μTASWako i30 immunoanalyzer. All biomarkers were significantly associated with HCC recurrence. The hazard ratios (HRs) were 3.5 [95% confidence interval (CI), 1.9‐6.7; Pu2009<u20090.0001] for DCPu2009≥u20097.5 ng/mL and 2.8 (95% CI, 1.4‐5.4; Pu2009=u20090.002) for AFPu2009≥u2009250 ng/mL. The HR increased to 5.2 (95% CI, 2.3‐12.0; Pu2009<u20090.0001) when AFPu2009≥u2009250 ng/mL and DCP ≥7.5 ng/mL were considered together. When they were combined with the Milan criteria, the HR increased from 2.6 (95% CI, 1.4‐4.7; Pu2009=u20090.003) for outside the Milan criteria to 8.6 (95% CI, 3.0‐24.6; Pu2009<u20090.0001) for outside the Milan criteria and AFPu2009≥u2009250 ng/mL and to 7.2 (95% CI, 2.8‐18.1; Pu2009<u20090.0001) for outside the Milan criteria and DCP ≥7.5 ng/mL. Our findings suggest that biomarkers are useful for predicting the risk of HCC recurrence after transplantation. Using both biomarkers and the Milan criteria may be better than using the Milan criteria alone in optimizing the decision of liver transplantation eligibility. Liver Transpl 21:599–606, 2015.

Antitumor effect of FGFR inhibitors on a novel cholangiocarcinoma patient derived xenograft mouse model endogenously expressing an FGFR2-CCDC6 fusion protein

Cholangiocarcinoma is a highly lethal cancer with limited therapeutic options. Recent genomic analysis of cholangiocarcinoma has revealed the presence of fibroblast growth factor receptor 2 (FGFR2) fusion proteins in up to 13% of intrahepatic cholangiocarcinoma (iCCA). FGFR fusions have been identified as a novel oncogenic and druggable target in a number of cancers. In this study, we established a novel cholangiocarcinoma patient derived xenograft (PDX) mouse model bearing an FGFR2-CCDC6 fusion protein from a metastatic lung nodule of an iCCA patient. Using this PDX model, we confirmed the ability of the FGFR inhibitors, ponatinib, dovitinib and BGJ398, to modulate FGFR signaling, inhibit cell proliferation and induce cell apoptosis in cholangiocarcinoma tumors harboring FGFR2 fusions. In addition, BGJ398 appeared to be superior in potency to ponatinib and dovitinib in this model. Our findings provide a strong rationale for the investigation of FGFR inhibitors, particularly BGJ398, as a therapeutic option for cholangiocarcinoma patients harboring FGFR2 fusions.