Pathophysiology and Imaging Findings of Bile Duct Necrosis: A Rare but Serious Complication of Transarterial Therapy for Liver Tumors

Pathologic characterization of precursors and cholangiocarcinoma referring to peribiliary capillary plexus: a new pathologic approach to bile duct neoplasm

The peribiliary capillary plexus (PCP) regularly and densely lines the basal side of the lining epithelia of normal bile ducts. To determine the pathology of the PCP in high-grade biliary intraepithelial neoplasms (BilINs) and intraductal papillary neoplasms of the bile duct (IPNBs), a precursor of cholangiocarcinoma (CCA), and CCA. Seventy-six cases of surgically resected high-grade BilIN and 83 cases of IPNB were histopathologically examined using endothelial immunostaining of PCP; all cases of high-grade BilIN and 40 cases of IPNB were associated with invasive CCA. Invasive and preinvasive neoplasms were pathologically examined referring to a two-layer pattern composed of biliary lining epithelia and underlying PCP unique to the bile duct. All high-grade BilIIN cases had an underlying single layer of capillaries, similar to PCP (PCP-like capillaries). In 43% of the 83 cases of IPNB, these capillaries were regularly distributed in almost all stalks and intervening stroma of intraluminal neoplastic components, while in the remaining 57% of IPNB, capillaries were sparsely or irregularly distributed in intraluminal components showing cribriform or solid growth patterns composed of striking atypical neoplastic epithelia. Invasive carcinomas associated with high-grade BilIN and IPNB were not lined with capillaries. The loss of PCP-like capillaries underlying high-grade BilIN and in stalks or stroma of IPNB may be involved in the malignant progression of these precursors. Immunostaining of PCP could be a new pathological tool for the evaluation of malignant progression and vascular supply in CCA and its precursors.

Post-trans-arterial chemoembolization hepatic necrosis and biliary stenosis: Clinical charateristics and endoscopic approach

Liver cancer is the fifth most common tumor and the second highest death-related cancer in the world. Hepatocarcinoma (HCC) represents 90% of liver cancers. According to the Barcelona Clinic Liver Cancer group, different treatment options could be offered to patients in consideration of tumor burden, liver function, patient performance status and biochemical marker serum concentration such as alpha-fetoprotein. Trans-arterial chemoembolization (TACE) is the treatment of choice in patients with diagnosis of unresectable HCC not eligible for liver transplantation, and preserved arterial supply. TACE is known to be safe and its complications are generally mild such as post-TACE syndrome, a self-resolving adverse event that occurs in about 90% of patients after the procedure. However, albeit rarely, more severe adverse events such as biloma, sepsis, hepatic failure, chemoagents induced toxicities, and post-TACE liver necrosis can occur. A prompt diagnosis of these clinical conditions is fundamental to prevent further complications. As a result, biliary stenosis could be a rare post-TACE necrosis complication and can be difficult to manage. Complications from untreated biliary strictures include recurring infections, jaundice, chronic cholestasis, and secondary biliary cirrhosis.

Panic at the Bile Duct: How Intrahepatic Cholangiocytes Respond to Stress and Injury

In the liver, biliary epithelial cells (BECs) line intrahepatic bile ducts (IHBDs) and are primarily responsible for modifying and transporting hepatocyte-produced bile to the digestive tract. BECs comprise only 3% to 5% of the liver by cell number but are critical for maintaining choleresis through homeostasis and disease. To this end, BECs drive an extensive morphologic remodeling of the IHBD network termed ductular reaction (DR) in response to direct injury or injury to the hepatic parenchyma. BECs are also the target of a broad and heterogenous class of diseases termed cholangiopathies, which can present with phenotypes ranging from defective IHBD development in pediatric patients to progressive periductal fibrosis and cancer. DR is observed in many cholangiopathies, highlighting overlapping similarities between cell- and tissue-level responses by BECs across a spectrum of injury and disease. The following core set of cell biological BEC responses to stress and injury may moderate, initiate, or exacerbate liver pathophysiology in a context-dependent manner: cell death, proliferation, transdifferentiation, senescence, and acquisition of neuroendocrine phenotype. By reviewing how IHBDs respond to stress, this review seeks to highlight fundamental processes with potentially adaptive or maladaptive consequences. A deeper understanding of how these common responses contribute to DR and cholangiopathies may identify novel therapeutic targets in liver disease.

Prediction of bile duct injury after transarterial chemoembolization for hepatocellular carcinoma: Model establishment and verification

Objective

This study aimed to establish and validate a predictive model for bile duct injury in patients with hepatocellular carcinoma (HCC) after drug-eluting bead transarterial chemoembolization (DEB-TACE).

Methods

We retrospectively analyzed 284 patients with HCC treated with DEB-TACE at our hospital between January 2017 and December 2021, of whom 63 patients experienced postoperative bile duct injuries. Univariate and logistic multivariate regression analyses were performed to identify the risk factors for bile duct injury, as well as establish and internally validate the nomogram model. The area under the curve (AUC) of the receiver operating characteristic (ROC) curve, calibration curve, Hosmer-Lemeshow goodness of fit test, decision curve analysis (DCA), and clinical impact curve (CIC) were used to assess the predictive power, clinical value, and practicability of the nomogram model.

Results

The incidence of bile duct injuries after DEB-TACE was 22.18% (63/284), with one injury occurring in every 2.86 sessions of DEB-TACE treatment. Univariate and logistic multivariate regression analyses indicated that a history of hepatectomy (odds ratio [OR]=2.285; 95% confidence interval [CI]=1.066-4.898; P<0.05), subjective angiographic chemoembolization endpoint level (OR=1.832; 95% CI=1.258-2.667; P<0.05), alkaline phosphatase (OR=1.005; 95% CI=1.001-1.010; P<0.05), and platelet count (OR=1.005; 95% CI=1.001-1.009; P<0.05) were independent risk factors for bile duct injury after DEB-TACE among patients with HCC. The risk nomogram model based on the above four variables was validated using the bootstrap method, showing consistency between the predicted and experimental values. Furthermore, the model performed well in the Hosmer-Lemeshow goodness-of-fit test (²=3.648; P=0.887). The AUC of this model was 0.749 (95% CI=0.682-0.817), with an overall accuracy of 69.01%, a positive predictive value of 73.02%, a negative predictive value of 67.87%, a sensitivity of 73.0%, and a specificity of 67.90%, suggesting that the nomogram model had good accuracy and discrimination. In addition, DCA and CIC revealed a high clinical value and practicability of the model.

Conclusion

Bile duct injury in patients with HCC treated with DEB-TACE is caused by multiple factors rather than a single factor. The nomogram prediction model used in this study had a good fitting degree and prediction efficacy, with high clinical value and practicability.

The Risk Assessment and Clinical Research of Bile Duct Injury After Transcatheter Arterial Chemoembolization for Hepatocellular Carcinoma

Purpose

To retrospectively evaluate the risk factors and the clinical outcomes of bile duct injury after transcatheter arterial chemoembolization (TACE) for hepatocellular carcinoma (HCC) and to evaluate factors that aid clinical detection and subsequent treatment of the injured bile duct.

Materials and Methods

All patients undergoing TACE for HCC were retrospectively reviewed for identification of bile duct injury. The clinical spectrum of all the patients analyzed including patients’ demographics, laboratory data, radiologic imaging and mode of treatment.

Results

From January 2015 to December 2017, a total of 21 patients (4.3%) out of 483 patients with 693 TACE procedures were identified to have bile duct injury at our single institution. There were 17 males and 4 females, with a mean age of 59.8±11.6 years (range 34–84). About 14.3% (3/21) patients show the high-density shadow around the bile duct wall in one week non-enhanced CT, and 76.2% (16/21) cases ALP>200 U/L, all these patients showed bile duct injury on the subsequent follow-up CT. Post-TACE follow-up blood biochemistry showed that alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP) and gamma glutamyl transpeptidase (GGT) increased significantly compared with pre-TACE level. The incidence of various types of bile duct injuries on CT was intrahepatic bile duct dilatation (57.1%), biloma (25.7%) and hepatic hilar biliary strictures (17.1%), respectively. Patients with prior hepatectomy as well as proximal arterial chemoembolization carried a higher risk of post-TACE bile duct injury in terms of microvascular damage to the peribiliary capillary plexus.

Conclusion

Bile duct injury complicating TACE is not caused by a single factor, but by a variety of factors, and is closely related to the microvascular compromise of the bile ducts and subsequent chronic biliary infection. Lipiodol deposited along the bile duct wall and the sharp rise of ALP>200 U/L in one week after TACE can predict bile duct injury and early intervention may prevent the occurrence of serious complications. The probability of bile duct injury in patients with prior hepatectomy and proximal arterial chemoembolization increases significantly.