Clinical significance of CA 19-9 elevation during postoperative surveillance for extrahepatic bile duct cancer: a nomogram-based approach for the prediction of short-term recurrence

BACKGROUND

This study aimed to assess the significance of elevated carbohydrate antigen (CA) 19-9 in postoperative surveillance of extrahepatic bile duct cancer and to identify short-term recurrence predictors.

METHODS

This retrospective study included patients with elevated CA 19-9 post-curative surgery. Patients were categorized into positive and negative CT groups based on the detection of recurrence at CA 19-9 elevation. Short-term recurrence was defined as recurrence within 6 months in the negative CT group. We identified the factors associated with short-term recurrence and devised a predictive nomogram.

RESULTS

Among the 190 patients, 91 (47.9 %) exhibited tumor recurrence with CA 19-9 elevation (CT-positive group), whereas 99 (52.1 %) showed no recurrence (CT-negative group). In the CT-negative group (n = 99), 22 (22.2 %) experienced short-term tumor recurrence within 6 months. Preoperative CA 19-9 (odds ratio [OR]: 1.5, p = 0.016), postoperative CA 19-9 (OR: 1.9, p = 0.047), adjuvant treatment (OR: 3.5, p = 0.032), and the absence of inflammation (OR: 3.5, p = 0.045) were predictors of short-term recurrence. The area under the curve of the nomogram was 0.80 (95 % CI: 0.69-0.90).

CONCLUSION

Despite elevated CA 19-9 levels, approximately 50 % of patients exhibited no recurrence during postoperative surveillance for extrahepatic bile duct cancer. Factors influencing short-term recurrence encompass pre- and postoperative CA 19-9, adjuvant treatment, and inflammatory status.

Diagnostic cholangioscopy for surgical planning of extrahepatic cholangiocarcinoma

The recent clinical outcomes of multi-regimen chemotherapy included prolonged survival and a high rate of conversion to surgery in Asian patients with advanced biliary tract cancer. The ability of single-operator cholangioscopy (SOC) to detect and stage extrahepatic cholangiocarcinoma (CCC) in intraductal lesions is becoming more important in determining the extent of surgery. The aim of this study was to evaluate the role of SOC in surgical planning for extrahepatic CCC. We reviewed the consecutive data of patients who received nab-paclitaxel plus gemcitabine-cisplatin for the management of extrahepatic CCC and underwent preoperative evaluations between June 2020 and August 2022. SOC was performed to determine the precise extent of the disease in patients with a good response to chemotherapy who were considering surgical treatment. Among the 38 patients included, 30 (79%) were diagnosed with perihilar CCC, six (16%) with distal CCC, and two (5%) with intraductal papillary neoplasm of the bile duct. Intraductal evaluation with SOC altered disease extent defined by previous imaging findings in 14 (37%) patients. In those patients, five (36%) were changed to less extensive surgery, four (29%) to conversion surgery, four (29%) avoided surgery, and one (7%) was changed to more extensive surgery. Among the 38 included patients, 27 (71%) underwent surgery, and the accuracy of the visual impressions was 93%, as confirmed by the surgical pathology report. In conclusion, SOC examination of patients with potentially resectable extrahepatic CCC was more precise than conventional diagnostic evaluations and could help in planning surgical options.

Long-term outcomes of hepatopancreatoduodenectomy for perihilar cholangiocarcinoma: A comparative study with conventional hepatectomy

INTRODUCTION

Hepatopancreatoduodenectomy (HPD) is necessary to achieve a reliable margin-negative resection for widespread perihilar cholangiocarcinoma (PhCC), yet data on long-term outcomes following HPD for PhCC remain limited.

MATERIALS AND METHODS

A retrospective cohort study was conducted on 167 patients with PhCC who underwent surgery with curative-intent between 2000 and 2023. Hepatic resection and extrahepatic bile duct resection (Hr-BDR) were performed for cases presumed to have localized tumors, while HPD was conducted for cases with presumed extensive tumor spread. Short- and long-term outcomes, including surgery details, pathological findings, postoperative complications, survival rates, and recurrence patterns, were compared.

RESULTS

Forty-five patients underwent HPD and 122 underwent Hr-BDR. No differences were observed in the T or N factors of the TNM staging between both groups (P = 0.09 and 0.09). Overall postoperative significant complications (38 % vs. 34 %, P = 0.62), 90-day mortality rates (2 % vs. 2 %, P = 0.80), and 5-year cancer-specific survival (45 % vs. 40 %, P = 0.81) were comparable between both groups. However, the 5-year survival rate of the HPD group was significantly higher than that of the Hr-BDR group with positive invasive duodenal-side ductal margins (45 % vs. 0 %, P = 0.03). Local and remnant bile duct recurrence were significantly less frequent in the HPD than in the Hr-BDR group (20 % vs. 37 %, P = 0.04; 11 % vs. 0 %, P = 0.02, respectively).

CONCLUSION

Although HPD for widespread PhCC requires careful postoperative management, it has the potential to provide excellent long-term outcomes, and it should be considered proactively.

Artificial Intelligence and Radiomics in Cholangiocarcinoma: A Comprehensive Review

Cholangiocarcinoma (CCA) is a malignant biliary system tumor and the second most common primary hepatic neoplasm, following hepatocellular carcinoma. CCA still has an extremely high unfavorable prognosis, regardless of type and location, and complete surgical resection remains the only curative therapeutic option; however, due to the underhanded onset and rapid progression of CCA, most patients present with advanced stages at first diagnosis, with only 30 to 60% of CCA patients eligible for surgery. Recent innovations in medical imaging combined with the use of radiomics and artificial intelligence (AI) can lead to improvements in the early detection, characterization, and pre-treatment staging of these tumors, guiding clinicians to make personalized therapeutic strategies. The aim of this review is to provide an overview of how radiological features of CCA can be analyzed through radiomics and with the help of AI for many different purposes, such as differential diagnosis, the prediction of lymph node metastasis, the defining of prognostic groups, and the prediction of early recurrence. The combination of radiomics with AI has immense potential. Still, its effectiveness in practice is yet to be validated by prospective multicentric studies that would allow for the development of standardized radiomics models.

Imaging cholangiocarcinoma: CT and MRI techniques

Cross-sectional imaging plays a crucial role in the detection, diagnosis, staging, and resectability assessment of intra- and extrahepatic cholangiocarcinoma. Despite this vital function, there is a lack of standardized CT and MRI protocol recommendations for imaging cholangiocarcinoma, with substantial differences in image acquisition across institutions and vendor platforms. In this review, we present standardized strategies for the optimal imaging assessment of cholangiocarcinoma including contrast media considerations, patient preparation recommendations, optimal contrast timing, and representative CT and MRI protocols with individual sequence optimization recommendations. Our recommendations are supported by expert opinion from members of the Society of Abdominal Radiology's Disease-Focused Panel (DFP) on Cholangiocarcinoma, encompassing a broad array of institutions and practice patterns.

Long-term survival of stage 4 gallbladder cancer after extended radical surgery plus limited chemotherapy: a case report

Gallbladder cancers (GBC) are insidious, malignant, and associated with poor prognosis, with a 5-year survival rate of 5%. Long-term survival in advanced GBC is rare. Here, we report a case of a 45-year-old female who presented with intermittent right upper quadrant pain for 1 month. A gallbladder mass and two liver masses were identified on a computed tomography (CT) scan of the abdomen and pelvis with intravenous contrast, which was highly suspicious for GBC. The patient underwent extended radical surgery, and a low to moderately differentiated gallbladder adenocarcinoma was diagnosed through pathology. Postoperatively, the patient received chemotherapy with gemcitabine and cisplatin but only tolerated one cycle. The patient has been disease-free for over 7 years, representing an unusually long survival.

Preoperative Imaging Assessment and Staging of Perihilar Cholangiocarcinoma: Tips and Pitfalls

This article outlines the systematic radiological approach preoperative evaluation of perihilar cholangiocarcinoma (pCCA) using CT and MRI to provide key information regarding the suitability for curative surgical resection. It discusses older classification systems (Bismuth-Corlette, Memorial Sloan Kettering Cancer Center T staging) and follows the Korean Society of Abdominal Radiology 2019 consensus recommendations for step-by-step assessment. The correlation between radiological, surgical, and pathological findings is illustrated through a pictorial review of pathologically proven cases. Benign and malignant mimics of pCCA are included to provide a comprehensive overview.

LI-RADS Category Can Be a Post-Surgical Prognostic Factor for Intrahepatic Cholangiocarcinoma in Patients with Liver Cirrhosis or Chronic Hepatitis B

Introduction

The Liver Imaging Reporting and Data System (LI-RADS) categorization has been proposed as a potential prognostic indicator for primary liver neoplasms in patients with liver cirrhosis or chronic hepatitis B. This multicenter study aimed to determine whether LI-RADS categorization can offer additional post-surgical prognostic value for intrahepatic cholangiocarcinoma (ICCA) when used in conjunction with the American Joint Committee on Cancer (AJCC) guidelines.

Methods

Patients with high risk for hepatocellular carcinoma, surgically confirmed ICCAs, and available preoperative MRI were enrolled. LI-RADS categorization of ICCAs was performed using MRI features, and multivariate analyses were conducted incorporating LI-RADS category, AJCC staging, and clinicopathologic factors to evaluate their predictive value for postoperative recurrence-free survival (RFS) and overall survival (OS). In patients with early recurrence (<2 years), the percentages of AJCC stage I and LR-M or LR tumor-in-vein (TIV) were calculated, respectively.

Results

Among the 166 ICCAs analyzed, 13.3% (22/166) were classified as LR-4/5, 77.7% (129/166) as LR-M, and 9.0% (15/166) as LR TIV. Classifications according to the 8th AJCC guidelines for patients with available post-surgical pathologic data and follow-up imaging were 40.6% (63/155) stage I tumors, 23.9% (37/155) stage II, and 35.5% (55/155) stage III. Multivariate analysis revealed that LI-RADS category (LR-M or LR-TIV) was a significant factor for predicting both RFS (hazard ratio [HR] = 2.86, p = 0.02) and OS (HR = 3.18, p = 0.03). Additionally, AJCC staging (II or III) was a significant factor for RFS (HR = 3.90, p < 0.001) and OS (HR = 3.29, p < 0.001), male sex was a significant factor for RFS (HR = 1.89, p = 0.006) and OS (HR = 2.23, p = 0.002), and positive resection margin was a significant factor for OS (HR = 1.91, p = 0.03). Among the 80 patients with early recurrence, 97.5% displayed LR-M or LR-TIV features, while 11.3% were AJCC stage I patients.

Conclusion

The MRI-based preoperative LI-RADS categorization of ICCA provides additional post-surgical prognostic value beyond the AJCC guidelines, with significant implications for both RFS and OS.

Ultrasound-guided percutaneous biopsy for challenging perihilar focal liver lesions: diagnostic accuracy and safety assessment

PURPOSE

In cases of perihilar focal liver lesions, distinguishing between benign strictures and malignancies is critical to prevent unnecessary surgery. Although the use of contrast-enhanced CT or MRI in combination with clinical and laboratory findings can aid in diagnosis, histologic examination is often necessary. Histologic specimens can be obtained through various techniques, including ERCP-guided brush cytology or intraductal biopsy, cholangioscopy-directed biopsy or endoscopic ultrasound (EUS). However, these methods have been associated with suboptimal sensitivity and specificity, sometimes leading to inconclusive results. Therefore, ultrasound-guided percutaneous biopsy (US-guided PB) may play a crucial role, but data is lacking for perihilar lesions. The objective of our study was to assess the technical feasibility and safety of US-guided PB for perihilar lesions.

METHODS

We included 20 consecutive patients who underwent US-guided PB of perihilar liver lesions that were not suitable for surgery between June 2018 and October 2023.

RESULTS

All samples were obtained using a Menghini needle 20G and were adequate for histological examination, with a mean diameter of 12.3 mm (range 3-40 mm). Out of the 20 patients, 11 were diagnosed with malignancy while the remaining 9 had inflammatory or fibrotic tissue samples. No adverse events related to the procedure were reported.

CONCLUSION

US-guided PB of perihilar liver lesions is a valuable and safe diagnostic approach to consider for patients who are not suitable for surgery.

Probability of Lymph Node Metastases in Patients Undergoing Adequate Lymphadenectomy during Surgery for Intrahepatic Cholangiocarcinoma: A Retrospective Multicenter Study

Introduction: Nodal metastases (lymph node metastasis [LNM]) are one of the major determinants of prognosis following surgery for intrahepatic cholangiocarcinoma (ICC). Previous studies investigating the correlation between clinical-radiological features and the probability of LNM include patients undergoing inadequate nodal sampling. Aim of this study was to develop a model to predict the risk of LNM in patients undergoing adequate lymphadenectomy using preoperative clinical and radiological features. Methods: Patients undergoing radical surgery for ICC with adequate lymphadenectomy at seven Italian Centers between 2000 and 2023 were collected and divided into a derivation and a validation cohort. Logistic regression and dominance analysis were applied in the derivation cohort to identify variables associated with LNM at pathology. The final coefficients were derived from the model having the highest c-statistic in the derivation cohort with the lowest number of variables included (parsimony). The model was then tested in the external validation cohort, and the linear predictor was divided into quartiles to generate four risk categories. Results: A total of 693 patients were identified. Preoperative CA 19-9, clinically suspicious lymph nodes at radiology, patients’ age, and tumor burden score were significantly associated with LNM. These factors were included in a model (<ext-link ext-link-type="uri" xlink:href="https://aicep.website/calculators/" xmlns:xlink="http://www.w3.org/1999/xlink">https://aicep.website/calculators/</ext-link>) showing a c-statistic of 0.723 (95% CI: 0.680, 0.766) and 0.771 (95% CI: 0.699, 0.842) in the derivation and validation cohort, respectively. A progressive increase of pathological lymph node positivity across risk groups was observed (29.9% in low-risk, 45.1% in intermediate-low risk, 51.5% in intermediate-high risk, and 87.3% in high-risk patients; p = 0.001). Conclusions: A novel model that combines preoperative CA 19-9, clinically suspicious lymph nodes at radiology, patients’ age, and tumor burden score was developed to predict the risk of LNM before surgery. The model exhibited high accuracy and has the potential to assist clinicians in the management of patients who are candidate to surgery.

Management of intrahepatic and perihilar cholangiocarcinomas: Guidelines of the French Association for the Study of the Liver (AFEF)

Intrahepatic cholangiocarcinoma (iCCA) is the second most common malignant primary liver cancer. iCCA may develop on an underlying chronic liver disease and its incidence is growing in relation with the epidemics of obesity and metabolic diseases. In contrast, perihilar cholangiocarcinoma (pCCA) may follow a history of chronic inflammatory diseases of the biliary tract. The initial management of CCAs is often complex and requires multidisciplinary expertise. The French Association for the Study of the Liver wished to organize guidelines in order to summarize the best evidence available about several key points in iCCA and pCCA. These guidelines have been elaborated based on the level of evidence available in the literature and each recommendation has been analysed, discussed and voted by the panel of experts. They describe the epidemiology of CCA as well as how patients with iCCA or pCCA should be managed from diagnosis to treatment. The most recent developments of personalized medicine and use of targeted therapies are also highlighted.

Comparison of Machine Learning Models Using Diffusion-Weighted Images for Pathological Grade of Intrahepatic Mass-Forming Cholangiocarcinoma

Is the radiomic approach, utilizing diffusion-weighted imaging (DWI), capable of predicting the various pathological grades of intrahepatic mass-forming cholangiocarcinoma (IMCC)? Furthermore, which model demonstrates superior performance among the diverse algorithms currently available? The objective of our study is to develop DWI radiomic models based on different machine learning algorithms and identify the optimal prediction model. We undertook a retrospective analysis of the DWI data of 77 patients with IMCC confirmed by pathological testing. Fifty-seven patients initially included in the study were randomly assigned to either the training set or the validation set in a ratio of 7:3. We established four different classifier models, namely random forest (RF), support vector machines (SVM), logistic regression (LR), and gradient boosting decision tree (GBDT), by manually contouring the region of interest and extracting prominent radiomic features. An external validation of the model was performed with the DWI data of 20 patients with IMCC who were subsequently included in the study. The area under the receiver operating curve (AUC), accuracy (ACC), precision (PRE), sensitivity (REC), and F1 score were used to evaluate the diagnostic performance of the model. Following the process of feature selection, a total of nine features were retained, with skewness being the most crucial radiomic feature demonstrating the highest diagnostic performance, followed by Gray Level Co-occurrence Matrix lmc1 (glcm-lmc1) and kurtosis, whose diagnostic performances were slightly inferior to skewness. Skewness and kurtosis showed a negative correlation with the pathological grading of IMCC, while glcm-lmc1 exhibited a positive correlation with the IMCC pathological grade. Compared with the other three models, the SVM radiomic model had the best diagnostic performance with an AUC of 0.957, an accuracy of 88.2%, a sensitivity of 85.7%, a precision of 85.7%, and an F1 score of 85.7% in the training set, as well as an AUC of 0.829, an accuracy of 76.5%, a sensitivity of 71.4%, a precision of 71.4%, and an F1 score of 71.4% in the external validation set. The DWI-based radiomic model proved to be efficacious in predicting the pathological grade of IMCC. The model with the SVM classifier algorithm had the best prediction efficiency and robustness. Consequently, this SVM-based model can be further explored as an option for a non-invasive preoperative prediction method in clinical practice.

CT Texture Analysis of Perihilar Cholangiocarcinoma-Associations With Tumor Grading, Tumor Markers and Clinical Outcome

BACKGROUND

Texture analysis derived from computed tomography (CT) may provide clinically relevant imaging biomarkers associated with tumor histopathology. Perihilar cholangiocarcinoma is a malignant disease with an overall poor prognosis.

AIMS

The present study sought to elucidate possible associations between texture features derived from CT images with grading, tumor markers, and survival in extrahepatic, perihilar cholangiocarcinomas tumors.

METHODS

This retrospective study included 22 patients (10 females, 45%) with a mean age of 71.8 ± 8.7 years. Texture analysis was performed using the free available Mazda software. All tumors were histopathologically confirmed. Survival and clinical parameters were used as primary study outcomes.

RESULTS

In discrimination analysis, "S(1,1)SumVarnc" was statistically significantly different between patients with long-term survival and nonlong-term survival (mean 275.8 ± 32.6 vs. 239.7 ± 26.0, p = 0.01). The first-order parameter "skewness" was associated with the tumor marker "carcinoembryonic antigen" (CEA) (r = -0.7, p = 0.01). A statistically significant correlation of the texture parameter "S(5,0)SumVarnc" with tumor grading was identified (r = -0.6, p < 0.01). Several other texture features correlated with tumor markers CA-19-9 and AFP, as well as with T and N stage of tumors.

CONCLUSION

Several texture features derived from CT images were associated with tumor characteristics and survival in patients with perihilar cholangiocarcinomas. CT texture features could be used as valuable novel imaging markers in clinical routine.

The Constellation of Risk Factors and Paraneoplastic Syndromes in Cholangiocarcinoma: Integrating the Endocrine Panel Amid Tumour-Related Biology (A Narrative Review)

Cholangiocarcinomas (CCAs), a heterogeneous group of challenging malignant tumours which originate from the biliary epithelium, are associated with an alarming increasing incidence during recent decades that varies between different regions of the globe. Thus, awareness represents the key operating factor. Our purpose was to overview the field of CCAs following a double perspective: the constellation of the risk factors, and the presence of the paraneoplastic syndromes, emphasizing the endocrine features amid the entire multidisciplinary panel. This is a narrative review. A PubMed-based search of English-language original articles offered the basis of this comprehensive approach. Multiple risk factors underlying different levels of statistical evidence have been listed such as chronic biliary diseases and liver conditions, inflammatory bowel disease, parasitic infections (e.g., Opisthorchis viverrini, Clonorchis sinensis), lifestyle influence (e.g., alcohol, smoking), environmental exposure (e.g., thorotrast, asbestos), and certain genetic and epigenetic interplays. With regard to the endocrine panel, a heterogeneous spectrum should be taken into consideration: non-alcoholic fatty liver disease, obesity, type 2 diabetes mellitus, and potential connections with vitamin D status, glucagon-like peptide 1 receptor, or the galanin system, respectively, with exposure to sex hormone therapy. Amid the numerous dermatologic, hematologic, renal, and neurologic paraneoplastic manifestations in CCAs, the endocrine panel is less described. Humoral hypercalcaemia of malignancy stands as the most frequent humoral paraneoplastic syndrome in CCAs, despite being exceptional when compared to other paraneoplastic (non-endocrine) manifestations and to its reported frequency in other (non-CCAs) cancers (it accompanies 20-30% of all cancers). It represents a poor prognosis marker in CCA; it may be episodic once the tumour relapses. In addition to the therapy that targets the originating malignancy, hypercalcaemia requires the administration of bisphosphonates (e.g., intravenous zoledronic acid) or denosumab. Early detection firstly helps the general wellbeing of a patient due to a prompt medical control of high serum calcium and it also provides a fine biomarker of disease status in selected cases that harbour the capacity of PTHrP secretion. The exact molecular biology and genetic configuration of CCAs that display such endocrine traits is still an open matter, but humoral hypercalcaemia adds to the overall disease burden.

A special case of intrahepatic cholangiocarcinoma misdiagnosed as hepatic cystic echinococcosis

Intrahepatic cholangiocarcinoma (iCCA) is a prevalent liver tumor that presents a diagnostic challenge due to its nonspecific symptoms, necessitating reliance on imaging techniques for accurate diagnosis. The similarity of imaging features with other liver diseases, such as hepatocellular carcinoma (HCC) and hepatic alveolar echinococcosis, often leads to confusion and misdiagnosis. In contrast, the distinct characteristics of hepatic cystic echinococcosis (HCE) result in fewer reported misdiagnoses. A case involving a 53-year-old female from Changji (Xinjiang, China) diagnosed with iCCA, who was hospitalized for symptoms of upper abdominal distension and pain, along with nausea and vomiting, is presented. The patient underwent a partial hepatectomy in 1990 for hepatic echinococcosis. Abdominal computed tomography revealed multiple, quasicircular, low-density masses in the hilar region and right anterior lobe of the liver, with the largest measuring 5.61 cm × 4.84 cm. Enhanced computed tomography did not reveal significant enhancement of the lesion. Considering epidemiological factors, medical history, and imaging findings, the initial diagnosis was HCE, which prompted surgical intervention. The diagnosis of iCCA with necrosis was confirmed via pathological examination. The literature and relevant sources were consulted to establish that biliary tract tumors with necrosis or mucin production typically do not exhibit significant enhancement in enhanced scans, maintaining a consistently low density across all phases, resembling the presentation of HCE. When making diagnoses based on imaging data, it is essential to have knowledge of both the typical features and unique manifestations of the disease. In specific instances, relying solely on epidemiology and medical history may lead to incorrect conclusions. Therefore, comprehensive consideration of all aspects is necessary to prevent missed diagnoses and misdiagnoses.

An Unusual Radiologic Image of Extensive Tumor Mass Infiltrating Hepatic Hilum without Signs of Cholestasis-A Case Report and a Literature Review of Non-Cancerous Lesions Mimicking Intrahepatic Cholangiocarcinoma

BACKGROUND

Mass-forming intrahepatic cholangiocarcinoma (mICC) is the most frequent type of ICC. In contrast-enhanced computed tomography, mICC is visualized as a hypodense lesion with distal dilatation of intrahepatic bile ducts. The presented case illustrates the unusual manifestation of mICC in a 71-year-old male patient, where despite the extensive tumor mass and the hilar infiltration, the dilatation of intrahepatic bile ducts and cholestasis were not noted.

METHODS

A literature review on PubMed was performed. Primarily, 547 records were identified, and the titles and abstracts were systematically searched. Regarding the inclusion and exclusion criteria, 31 papers describing the non-cancerous liver lesions mimicking ICC were included in the further analysis.

RESULTS

In 41.9% of the analyzed non-cancerous lesions, the obstruction of the bile ducts was not noted, similar to our patient. A significant cholestasis has been found in 30.03% of analyzed patients. The invasion of the liver hilum was noted in one-third of the patients.

CONCLUSIONS

Atypical radiological features in lesions suspected of ICC, such as the absence of intrahepatic bile-duct dilation, are common in benign lesions. In the case of radiologically atypical lesions suspected of ICC, the diagnostic imaging needs to be correlated with clinical data, and the diagnosis should be confirmed with a pathological examination.

Intraductal papillary neoplasm of the bile duct: diagnostic value of MRI features in differentiating pathologic subclassifications-type 1 versus type 2

OBJECTIVES

To identify MRI features for differentiating type 2 from type 1 intraductal papillary neoplasms of bile duct (IPNB) and assessing malignant potential of IPNB.

METHODS

This retrospective study included 60 patients with surgically proven IPNB who had undergone preoperative MRI between January 2007 and December 2020. All surgical specimens were reviewed retrospectively to classify types 1 and 2 IPNBs and assess tumor grade. Significant MRI features for differentiating type 2 (n = 40) from type 1 IPNB (n = 20); and for IPNB with an associated invasive carcinoma (n = 43) from intraepithelial neoplasia (n = 17) were determined using logistic regression analysis.

RESULTS

An associated invasive carcinoma was more frequently found in type 2 than in type 1 IPNB (85.0% [34/40] vs. 45.0% [9/20], p = 0.003). At univariable analysis, MRI features including extrahepatic location, no dilatation of tumor-bearing segment of bile duct, isolated upstream bile duct dilatation, and single lesion were associated with type 2 IPNB (all p ≤ 0.012). At multivariable analysis, significant MRI findings for differentiating type 2 from type 1 IPNB were extrahepatic location and no dilatation of tumor-bearing segment of bile duct (odds ratio [OR], 7.24 and 46.40, respectively). At univariable and multivariable analysis, tumor size ≥ 2.5 cm (OR, 8.45), bile duct wall thickening (OR, 4.82), and irregular polypoid or nodular tumor shape (OR, 6.44) were significant MRI features for differentiating IPNB with an associated invasive carcinoma from IPNB with intraepithelial neoplasia.

CONCLUSION

MRI with MR cholangiopancreatography may be helpful in differentiating type 2 IPNB from type 1 IPNB and assessing malignant potential of IPNB.

CLINICAL RELEVANCE STATEMENT

Preoperative MRI with MR cholangiopancreatography may be helpful in differentiating type 2 intraductal papillary neoplasms of bile duct (IPNB) from type 1 IPNB and assessing malignant potential of IPNB.

KEY POINTS

• In terms of tumor grade, the incidence of invasive carcinoma was significantly higher in type 2 intraductal papillary neoplasm of the bile duct (IPNB) than in type 1 IPNB. • At MRI, extrahepatic location and no dilatation of tumor-bearing segment are significant features for differentiating type 2 IPNBs from type 1 IPNBs. • At MRI, large tumor size, bile duct wall thickening, and irregular polypoid or nodular tumor shape are significant features for differentiating IPNB with an associated invasive carcinoma from IPNB with intraepithelial neoplasia.

Clinical features and prediction of long-term survival after surgery for perihilar cholangiocarcinoma

INTRODUCTION

The treatment of perihilar Cholangiocarcinoma (pCCA) poses specific challenges not only due to its high perioperative complication rates but also due its dismal long-term prognosis with only a few long-term survivors (LTS) among the patients. Therefore, in this analysis characteristics and predictors of LTS in pCCA patients are investigated.

MATERIAL AND METHODS

In this single center analysis, patients undergoing curative-intent liver resection for pCCA between 2010 and 2022 were categorized into long-term and short-term survivors (STS) excluding perioperative mortality. Binary logistic regression was used to determine key differences between the groups and to develop a prognostic composite variable. This composite variable was subsequently tested in the whole cohort of surgically treated pCCA patients using Cox Regression analysis for cancer-specific survival (CSS).

RESULTS

Within a cohort of 209 individuals, 27 patients were identified as LTS (median CSS = 125 months) and 55 patients as STS (median CSS = 16 months). Multivariable analysis identified preoperative portal vein infiltration (OR = 5.85, p = 0.018) and intraoperative packed red blood cell (PRBC) transfusions (OR = 10.29, p = 0.002) as key differences between the groups. A prognostic composite variable based on these two features was created and transferred into a Cox regression model of the whole cohort. Here, the composite variable (HR = 0.35, p<0.001), lymph node metastases (HR = 2.15, p = 0.001) and postoperative complications (HR = 3.06, p<0.001) were identified as independent predictors of CSS.

CONCLUSION

Long-term survival after surgery for pCCA is possible and is strongly negatively associated with preoperative portal vein infiltration and intraoperative PRBC transfusion. As these variables are part of preoperative staging or can be modulated by intraoperative technique, the proposed prognostic composite variable can easily be transferred into clinical management to predict the oncological outcome of patients undergoing surgery for pCCA.

Imaged periductal infiltration: Diagnostic and prognostic role in intrahepatic mass-forming cholangiocarcinoma

Purpose

This study examines periductal infiltration in intrahepatic mass-forming cholangiocarcinoma (IMCC), focusing on its importance for differentiating hepatic tumors and its influence on post-surgical survival in IMCC patients.

Methods

Eighty-three consecutive patients with IMCC (n = 43) and liver cancer whose preoperative images showed intrahepatic bile duct dilatation adjacent to the tumor for differential diagnosis from hepatocellular carcinoma (HCC) [n = 21], metastatic liver cancer (MLC) [n = 16] and combined hepatocellular-cholangiocarcinoma (cHCC-CC) [n = 3] were enrolled. CT and MRI findings of simple bile duct compression, imaged periductal infiltration, and imaged intrabiliary growth adjacent to the main tumor were reviewed. Clinicopathological and imaging features were compared in each group. The sensitivity, specificity, and odds ratio were calculated for each imaging finding of IMCC versus the other tumor groups. Overall survival was compared between cases of IMCC with and without imaged periductal infiltration.

Results

Simple bile duct compression and imaged intrabiliary growth were more frequently observed in HCC than in the others (p < 0.0001 and 0.040, respectively). Imaged periductal infiltration was observed more often in histopathologically confirmed large-duct type IMCC than in the small-duct type IMCC (p = 0.034). Multivariable analysis demonstrated that only imaged periductal infiltration (odds ratio, 50.67) was independently correlated with IMCC. Patients with IMCC who had imaged periductal infiltration experienced a poorer prognosis than those without imaged periductal infiltration (p = 0.0034).

Conclusion

Imaged periductal infiltration may serve as a significant marker for differentiating IMCC from other liver cancers. It may also have the potential to predict post-surgical outcomes in patients with IMCC.

High Bile Titer and High Bile to Serum Ratio of CYFRA 21 - 1 Reliably Discriminate Malignant Biliary Obstruction Caused by Cholangiocarcinoma

INTRODUCTION

Previously we demonstrated that elevated serum CYFRA 21 - 1 is a reliable diagnostic and prognostic biomarker for biliary tract cancers. This study aims to explore the diagnostic performance of bile CYFRA 21 - 1 (bCYFRA 21 - 1) in discriminating malignant biliary obstruction (MBO) caused by cholangiocarcinoma (CCA).

METHODS

77 CCA patients ((17 intrahepatic CCA (iCCA), 49 perihilar CCA (pCCA) and 11 distal CCA (dCCA)) and 43 benign patients with biliary obstruction were enrolled. Serum and bile levels of CYFRA 21 - 1, carcinoembryonic antigen (CEA) and carbohydrate antigen 19 - 9 (CA19-9) were quantified. Diagnostic performances of these biomarkers were estimated by receiver operator characteristic curves. Subgroups analysis of these tumor markers among CCA subtypes was performed.

RESULTS

High bCYFRA 21 - 1 (cut-off value of 59.25 ng/mL with sensitivity of 0.889 and specificity of 0.750) and high bile to serum ratio of CYFRA 21 - 1 (b/sCYFRA 21 - 1, cut-off value of 31.55 with sensitivity of 0.741 and specificity of 0.778) achieved better diagnostic performance than any other biomarker in discriminating MBO. Subgroup analysis revealed that bCYFRA 21 - 1 was significantly elevated in all CCA subtypes; moreover b/sCYFRA 21 - 1 was upregulated in pCCA and dCCA (the mean b/sCYFRA 21 - 1 of pCCA was highest among CCA subtypes: 57.90, IQR 29.82-112.27).

CONCLUSIONS

Both high biliary CYFRA 21 - 1 and high bile to serum ratio of CYFRA 21 - 1 were reliable diagnostic biomarkers for MBO caused by CCA.

Practice guidelines for managing extrahepatic biliary tract cancers

Backgrounds/Aims

Reported incidence of extrahepatic bile duct cancer is higher in Asians than in Western populations. Korea, in particular, is one of the countries with the highest incidence rates of extrahepatic bile duct cancer in the world. Although research and innovative therapeutic modalities for extrahepatic bile duct cancer are emerging, clinical guidelines are currently unavailable in Korea. The Korean Society of Hepato-Biliary-Pancreatic Surgery in collaboration with related societies (Korean Pancreatic and Biliary Surgery Society, Korean Society of Abdominal Radiology, Korean Society of Medical Oncology, Korean Society of Radiation Oncology, Korean Society of Pathologists, and Korean Society of Nuclear Medicine) decided to establish clinical guideline for extrahepatic bile duct cancer in June 2021.

Methods

Contents of the guidelines were developed through subgroup meetings for each key question and a preliminary draft was finalized through a Clinical Guidelines Committee workshop.

Results

In November 2021, the finalized draft was presented for public scrutiny during a formal hearing.

Conclusions

The extrahepatic guideline committee believed that this guideline could be helpful in the treatment of patients.

Imaging features of malignant vs stone-induced biliary obstruction: Aspects to consider

Radiological studies play a crucial role in the evaluation of patients with biliary duct obstruction, allowing for the guidance of clinical diagnosis towards a malignant or stone-induced etiology through the recognition of relevant imaging features, which must be continuously revisited given their prognostic significance. This article aims to emphasize the importance of recognizing crucial imaging aspects of malignant and stone-induced biliary obstruction.

Cholangiocarcinoma combined with biliary obstruction: an exosomal circRNA signature for diagnosis and early recurrence monitoring

Cholangiocarcinoma (CCA) is a highly malignant biliary tract cancer with currently suboptimal diagnostic and prognostic approaches. We present a novel system to monitor CCA using exosomal circular RNA (circRNA) via serum and biliary liquid biopsies. A pilot cohort consisting of patients with CCA-induced biliary obstruction (CCA-BO, n = 5) and benign biliary obstruction (BBO, n = 5) was used to identify CCA-derived exosomal circRNAs through microarray analysis. This was followed by a discovery cohort (n = 20) to further reveal a CCA-specific circRNA complex (hsa-circ-0000367, hsa-circ-0021647, and hsa-circ-0000288) in both bile and serum exosomes. In vitro and in vivo studies revealed the three circRNAs as promoters of CCA invasiveness. Diagnostic and prognostic models were established and verified by two independent cohorts (training cohort, n = 184; validation cohort, n = 105). An interpreter-free diagnostic model disclosed the diagnostic power of biliary exosomal circRNA signature (Bile-DS, AUROC = 0.947, RR = 6.05) and serum exosomal circRNA signature (Serum-DS, AUROC = 0.861, RR = 4.04) compared with conventional CA19-9 (AUROC = 0.759, RR = 2.08). A prognostic model of CCA undergoing curative-intent surgery was established by calculating early recurrence score, verified with bile samples (Bile-ERS, C-index=0.783) and serum samples (Serum-ERS, C-index = 0.782). These models, combined with other prognostic factors revealed by COX-PH model, enabled the establishment of nomograms for recurrence monitoring of CCA. Our study demonstrates that the exosomal triple-circRNA panel identified in both bile and serum samples serves as a novel diagnostic and prognostic tool for the clinical management of CCA.

68 Ga-FAPI-04 PET/CT for the Evaluation of Cholangiocarcinoma : Comparison With 18 F-FDG PET/CT and Abdominal 68 Ga-FAPI-04 PET/MR

PURPOSE

In this study, we evaluated and compared the diagnostic performances of 68 Ga-FAPI-04 PET/CT and 18 F-FDG PET/CT for primary and metastatic cholangiocarcinoma (CCA) lesions. We also investigated the performance of PET/MR for visualizing and characterizing CCA and liver metastasis lesions.

PATIENTS AND METHODS

Forty-four patients with suspected CCA were recruited and underwent 68 Ga-FAPI-04 and 18 F-FDG PET/CT within 1 week, including 30 patients who underwent simultaneous abdominal 68 Ga-FAPI-04 PET/MR scanning. The findings were confirmed by histopathology or radiographic follow-up.

RESULTS

Compared with 18 F-FDG PET/CT, 68 Ga-FAPI-04 PET/CT showed higher sensitivity (94.3% vs 88.6%) and the same accuracy (86.4% vs 86.4%) in evaluating primary tumors. However, its specificity was lower (55.6% vs 77.8%). 68 Ga-FAPI-04 PET was superior to 18 F-FDG PET in both patient-based and lesion-based evaluations except for metastatic lesions in the liver and bone. For intrahepatic CCA, 68 Ga-FAPI-04 PET/CT and 18 F-FDG PET/CT (100% vs 100%) had similar detection rates, with similar uptake levels between tracers ( P > 0.05). However, for extrahepatic CCA, 68 Ga-FAPI-04 PET/CT had a higher detection rate (89.5% vs 78.9%), and 68 Ga-FAPI-04 had a higher uptake ( P < 0.05). PET/MR was more effective than PET/CT in terms of lesion conspicuity and diagnostic confidence for primary tumors and liver metastases. In addition, multisequence MRI identified more liver metastases than 68 Ga-FAPI-04 PET/CT and 18 F-FDG PET/CT.

CONCLUSIONS

Compared with 18 F-FDG PET/CT, 68 Ga-FAPI-04 PET/CT showed a higher sensitivity in detecting primary CCA tumors, involved lymph nodes, and peritoneal metastases. Compared with 68 Ga-FAPI-04 PET/CT, PET/MR detected primary and liver metastatic lesions more accurately. For extrahepatic CCA, the combination of 68 Ga-FAPI-04 PET/CT and abdominal PET/MRI may replace 18 F-FDG PET/CT.

Recent Advancement in Diagnosis of Biliary Tract Cancer through Pathological and Molecular Classifications

Biliary tract cancers (BTCs), including intrahepatic, perihilar, and distal cholangiocarcinomas, as well as gallbladder cancer, are a diverse group of cancers that exhibit unique molecular characteristics in each of their anatomic and pathological subtypes. The pathological classification of BTCs compromises distinct growth patterns, including mass forming, periductal infiltrating, and intraductal growing types, which can be identified through gross examination. The small-duct and large-duct types of intrahepatic cholangiocarcinoma have been recently introduced into the WHO classification. The presentation of typical clinical symptoms, as well as the extensive utilization of radiological, endoscopic, and molecular diagnostic methods, is thoroughly detailed in the description. To overcome the limitations of traditional tissue acquisition methods, new diagnostic modalities are being explored. The treatment landscape is also rapidly evolving owing to the emergence of distinct subgroups with unique molecular alterations and corresponding targeted therapies. Furthermore, we emphasize the crucial aspects of diagnosing BTC in practical clinical settings.

Cholangiocarcinoma imaging: from diagnosis to response assessment

Cholangiocarcinoma (CCA), a highly aggressive primary liver cancer arising from the bile duct epithelium, represents a substantial proportion of hepatobiliary malignancies, posing formidable challenges in diagnosis and treatment. Notably, the global incidence of intrahepatic CCA has seen a rise, necessitating a critical examination of diagnostic and management strategies, especially due to presence of close imaging mimics such as hepatocellular carcinoma (HCC) and combined hepatocellular carcinoma-cholangiocarcinoma (cHCC-CCA). Hence, it is imperative to understand the role of various imaging modalities such as ultrasound, computed tomography (CT), and magnetic resonance imaging (MRI), elucidating their strengths, and limitations in diagnostic precision and staging accuracy. Beyond conventional approaches, there is emerging significance of functional imaging tools including positron emission tomography (PET)-CT and diffusion-weighted (DW)-MRI, providing pivotal insights into diagnosis, therapeutic assessment, and prognostic evaluation. This comprehensive review explores the risk factors, classification, clinical features, and role of imaging in the holistic spectrum of diagnosis, staging, management, and restaging for CCA, hence serving as a valuable resource for radiologists evaluating CCA.

Recent Advances in Pathology of Intrahepatic Cholangiocarcinoma

Intrahepatic cholangiocarcinoma (ICCA) is a malignant epithelial neoplasm characterized by biliary differentiation within the liver. ICCA is molecularly heterogeneous and exhibits a broad spectrum of histopathological features. It is a highly aggressive carcinoma with high mortality and poor survival rates. ICCAs are classified into two main subtypes: the small-duct type and large-duct types. These two tumor types have different cell origins and clinicopathological features. ICCAs are characterized by numerous molecular alterations, including mutations in KRAS, TP53, IDH1/2, ARID1A, BAP1, BRAF, SAMD4, and EGFR, and FGFR2 fusion. Two main molecular subtypes-inflammation and proliferation-have been proposed. Recent advances in high-throughput assays using next-generation sequencing have improved our understanding of ICCA pathogenesis and molecular genetics. The diagnosis of ICCA poses a significant challenge for pathologists because of its varied morphologies and phenotypes. Accurate diagnosis of ICCA is essential for effective patient management and prognostic determination. This article provides an updated overview of ICCA pathology, focusing particularly on molecular features, histological subtypes, and diagnostic approaches.

Radiographic features predictive of recurrence and survival after surgical resection of perihilar cholangiocarcinoma

Objective

To study which radiographic features were associated with recurrence and adverse outcome in patients undergoing surgical resection of perihilar cholangiocarcinoma (PCCA), as well as to evaluate the imaging patterns that signify recurrence after the resection of PCCA.

Materials and methods

This study was conducted in a solitary tertiary center and utilized a retrospective, analytical, case-control design. The study population consisted of patients with pathologically confirmed PCCA who underwent surgical resection and were subsequently followed up from January 2009 to December 2017. A total of 77 patients were enrolled in the study and were categorized into two distinct groups, namely recurrent and non-recurrent. The analysis encompassed the examination of demographic data and recurrence patterns. Additionally, survival and multivariate analyses were employed to assess radiographic imaging data and surgical information.

Results

Seventy-seven patients diagnosed with PCCA based on pathological evidence were included in the study. Among the participants, there were 28 females and 49 males, with ages ranging from 41 to 81 years (mean age of 60.65 ± 7.66). A noteworthy finding was the recurrence rate of 65 % observed following surgical resection. The presence of regional lymph node (LN) metastasis, adjacent organ invasion, and surgical margin emerged as the three independent factors that exhibited a significant association with recurrence after post-operative resection (p = 0.023, p = 0.028, and p = 0.010, respectively). The patients with PCCA who experienced regional LN metastasis had a median overall survival (OS) of 22 months, which was significantly lower than the 46 months observed in those without regional LN metastasis (p < 0.018). Furthermore, the individuals with regional LN metastasis had a death rate that was 2.08 times higher than those without (p = 0.040). In addition, those with adjacent organ invasion had an OS duration of 21 months compared with 52 months in those without (p = 0.008), and the rate of death was 2.39 times higher (p = 0.018). Patients with an R1 resection margin had an OS duration of 36 months compared with 51.56 months in those with an R0 resection margin (p = 0.006), as well as a 2.13 times higher rate of recurrence (p = 0.010) and a 2.43 times higher mortality rate (p = 0.013).

Conclusion

The presence of regional LN metastasis, invasion of adjacent organs, and R1 resection margin were identified as distinct factors that are linked to both disease recurrence and reduced OS. Local recurrence, as well as the spread of cancer to distant organs such as the lungs and liver, were frequently observed patterns of recurrence. To enhance the precision of staging, prognosis, and treatment, the inclusion of periductal fat or invasion of adjacent organs should be considered in the staging system for PCCA.

Cholangiocarcinoma: Pathologic and Molecular Classification in the Era of Precision Medicine

CONTEXT.—

Cholangiocarcinoma (CCA) is a heterogeneous cancer of the bile duct, and its diagnosis is often challenging.

OBJECTIVE.—

To provide insights into state-of-the-art approaches for the diagnosis of CCA.

DATA SOURCES.—

Literature review via PubMed search and authors' experiences.

CONCLUSIONS.—

CCA can be categorized as intrahepatic or extrahepatic. Intrahepatic CCA is further classified into small-duct-type and large-duct-type, whereas extrahepatic CCA is classified into distal and perihilar according to site of origin within the extrahepatic biliary tree. Tumor growth patterns include mass forming, periductal infiltrating, and intraductal tumors. The clinical diagnosis of CCA is challenging and usually occurs at an advanced tumor stage. Pathologic diagnosis is made difficult by tumor inaccessibility and challenges in distinguishing CCA from metastatic adenocarcinoma to the liver. Immunohistochemical stains can assist in differentiating CCA from other malignancies, such as hepatocellular carcinoma, but no distinctive CCA-specific immunohistochemical profile has been identified. Recent advances in next-generation sequencing-based high-throughput assays have identified distinct genomic profiles of CCA subtypes, including genomic alterations that are susceptible to targeted therapies or immune checkpoint inhibitors. Detailed histopathologic and molecular evaluations of CCA by pathologists are critical for correct diagnosis, subclassification, therapeutic decision-making, and prognostication. The first step toward achieving these goals is to acquire a detailed understanding of the histologic and genetic subtypes of this heterogeneous tumor group. Here, we review state-of-the-art approaches that should be applied to establish a diagnosis of CCA, including clinical presentation, histopathology, staging, and the practical use of genetic testing methodologies.

Machine learning for differentiating between pancreatobiliary-type and intestinal-type periampullary carcinomas based on CT imaging and clinical findings

PURPOSE

To develop a diagnostic model for distinguishing pancreatobiliary-type and intestinal-type periampullary adenocarcinomas using preoperative contrast-enhanced computed tomography (CT) findings combined with clinical characteristics.

METHODS

This retrospective study included 140 patients with periampullary adenocarcinoma who underwent preoperative enhanced CT, including pancreaticobiliary (N = 100) and intestinal (N = 40) types. They were randomly assigned to the training or internal validation set in an 8:2 ratio. Additionally, an independent external cohort of 28 patients was enrolled. Various CT features of the periampullary region were evaluated and data from clinical and laboratory tests were collected. Five machine learning classifiers were developed to identify the histologic type of periampullary adenocarcinoma, including logistic regression, random forest, multi-layer perceptron, light gradient boosting, and eXtreme gradient boosting (XGBoost).

RESULTS

All machine learning classifiers except multi-layer perceptron used achieved good performance in distinguishing pancreatobiliary-type and intestinal-type adenocarcinomas, with the area under the curve (AUC) ranging from 0.75 to 0.98. The AUC values of the XGBoost classifier in the training set, internal validation set and external validation set are 0.98, 0.89 and 0.84 respectively. The enhancement degree of tumor, the growth pattern of tumor, and carbohydrate antigen 19-9 were the most important factors in the model.

CONCLUSION

Machine learning models combining CT with clinical features can serve as a noninvasive tool to differentiate the histological subtypes of periampullary adenocarcinoma, in particular using the XGBoost classifier.

Utilization of Radiomics Features Extracted From Preoperative Medical Images to Detect Metastatic Lymph Nodes in Cholangiocarcinoma and Gallbladder Cancer Patients: A Systemic Review and Meta-analysis

OBJECTIVES

This study aimed to determine the methodological quality and evaluate the diagnostic performance of radiomics features in detecting lymph node metastasis on preoperative images in patients with cholangiocarcinoma and gallbladder cancer.

METHODS

Publications between January 2005 and October 2022 were considered for inclusion. Databases such as Pubmed/Medline, Scopus, Embase, and Google Scholar were searched for relevant studies. The quality of the methodology of the manuscripts was determined using the Radiomics Quality Score and Quality Assessment of Diagnostic Accuracy Studies 2. Pooled results with corresponding 95% confidence intervals (CIs) were calculated using the DerSimonian-Liard method (random-effect model). Forest plots were used to visually represent the diagnostic profile of radiomics signature in each of the data sets pertaining to each study. Fagan plot was used to determine clinical applicability.

RESULTS

Overall sensitivity was 0.748 (95% CI, 0.703-0.789). Overall specificity was 0.795 (95% CI, 0.742-0.839). The combined negative likelihood ratio was 0.299 (95% CI, 0.266-0.350), and the positive likelihood ratio was 3.545 (95% CI, 2.850-4.409). The combined odds ratio of the studies was 12.184 (95% CI, 8.477-17.514). The overall summary receiver operating characteristics area under the curve was 0.83 (95% CI, 0.80-0.86). Three studies applied nomograms to 8 data sets and achieved a higher pooled sensitivity and specificity (0.85 [0.80-0.89] and 0.85 [0.71-0.93], respectively).

CONCLUSIONS

The pooled analysis showed that predictive models fed with radiomics features achieve good sensitivity and specificity in detecting lymph node metastasis in computed tomography and magnetic resonance imaging images. Supplementation of the models with biological correlates increased sensitivity and specificity in all data sets.

Radiomics and liver: Where we are and where we are headed?

Hepatic diffuse conditions and focal liver lesions represent two of the most common scenarios to face in everyday radiological clinical practice. Thanks to the advances in technology, radiology has gained a central role in the management of patients with liver disease, especially due to its high sensitivity and specificity. Since the introduction of computed tomography (CT) and magnetic resonance imaging (MRI), radiology has been considered the non-invasive reference modality to assess and characterize liver pathologies. In recent years, clinical practice has moved forward to a quantitative approach to better evaluate and manage each patient with a more fitted approach. In this setting, radiomics has gained an important role in helping radiologists and clinicians characterize hepatic pathological entities, in managing patients, and in determining prognosis. Radiomics can extract a large amount of data from radiological images, which can be associated with different liver scenarios. Thanks to its wide applications in ultrasonography (US), CT, and MRI, different studies were focused on specific aspects related to liver diseases. Even if broadly applied, radiomics has some advantages and different pitfalls. This review aims to summarize the most important and robust studies published in the field of liver radiomics, underlying their main limitations and issues, and what they can add to the current and future clinical practice and literature.

Liver Transplant for Intrahepatic Cholangiocarcinoma

Intrahepatic cholangiocarcinoma (iCCA) tends to be asymptomatic until late stages, leading most of the patients to present at advanced stages of the disease. A combination of medical and surgical therapy is crucial for patient management. Historically, poor outcomes resulted in liver transplantation being formally contraindicated for patients with iCCA; however, recent advances in patient selection and neoadjuvant therapy have resulted in a paradigm shift in liver transplant oncology. As a result, the feasibility of liver transplantation for iCCA is being reevaluated by several centers as a therapeutic alternative for select patients with locally advanced unresectable disease.

Radiomics using CT images for preoperative prediction of lymph node metastasis in perihilar cholangiocarcinoma: a multi-centric study

OBJECTIVES

To develop a CT-based radiomics model for preoperative prediction of lymph node (LN) metastasis in perihilar cholangiocarcinoma (pCCA).

METHODS

The study enrolled consecutive pCCA patients from three independent Chinese medical centers. The Boruta algorithm was applied to build the radiomics signature for the primary tumor and LN. The k-means algorithm was employed to cluster the selected LNs based on the radiomics signature LN. Support vector machines were used to construct the prediction models. The diagnostic efficiency was measured by the area under the receiver operating characteristic curve (AUC). The optimal model was evaluated in terms of calibration, clinical usefulness, and prognostic value.

RESULTS

A total of 214 patients were included in the study (mean age: 61.6 years ± 9.4; 130 male). The selected LNs were classified into two clusters, which were significantly correlated with LN metastasis in all cohorts (p < 0.001). The model incorporated the clinical risk factors, radiomics signature primary tumor, and the LN cluster obtained the best discrimination, with AUC values of 0.981 (95% CI: 0.962-1), 0.896 (95% CI: 0.810-0.982), and 0.865 (95% CI: 0.768-0.961) in the training, internal validation, and external validation cohorts, respectively. High-risk patients predicted by the optimal model had shorter overall survival than low-risk patients (median, 13.7 vs. 27.3 months, p < 0.001).

CONCLUSIONS

The study proposed a radiomics model with good performance to predict LN metastasis in pCCA. As a noninvasive preoperative prediction tool, this model may help in patient risk stratification and personalized treatment.

CLINICAL RELEVANCE STATEMENT

A CT-based radiomics model accurately predicts lymph node metastasis in perihilar cholangiocarcinoma patients. This noninvasive preoperative tool can aid in patient risk stratification and personalized treatment, potentially improving patient outcomes.

KEY POINTS

• The radiomics model based on contrast-enhanced CT is a useful tool for preoperative prediction of lymph node metastasis in perihilar cholangiocarcinoma. • Radiomics features extracted from lymph nodes show great potential for predicting lymph node metastasis. • The study is the first to identify a lymph node phenotype with a high probability of metastasis based on radiomics.

A multi-parameter intrahepatic cholangiocarcinoma scoring system based on modified contrast-enhanced ultrasound LI-RADS M criteria for differentiating intrahepatic cholangiocarcinoma from hepatocellular carcinoma

PURPOSE

To develop a multi-parameter intrahepatic cholangiocarcinoma (ICC) scoring system and compare its diagnostic performance with contrast-enhanced ultrasound (CEUS) liver imaging reporting and data system M (LR-M) criteria for differentiating ICC from hepatocellular carcinoma (HCC).

METHODS

This retrospective study enrolled 62 high-risk patients with ICCs and 62 high-risk patients with matched HCCs between January 2022 and December 2022 from two institutions. The CEUS LR-M criteria was modified by adjusting the early wash-out onset (within 45 s) and the marked wash-out (within 3 min). Then, a multi-parameter ICC scoring system was established based on clinical features, B-mode ultrasound features, and modified LR-M criteria.

RESULT

We found that elevated CA 19-9 (OR=12.647), lesion boundary (OR=11.601), peripheral rim-like arterial phase hyperenhancement (OR=23.654), early wash-out onset (OR=7.211), and marked wash-out (OR=19.605) were positive predictors of ICC, whereas elevated alpha-fetoprotein (OR=0.078) was a negative predictor. Based on these findings, an ICC scoring system was established. Compared with the modified LR-M and LR-M criteria, the ICC scoring system showed the highest area under the curve (0.911 vs. 0.831 and 0.750, both p<0.05) and specificity (0.935 vs. 0.774 and 0.565, both p<0.05). Moreover, the numbers of HCCs categorized as LR-M decreased from 27 (43.5%) to 14 (22.6%) and 4 (6.5%) using the modified LR-M criteria and ICC scoring system, respectively.

CONCLUSION

The modified LR-M criteria-based multi-parameter ICC scoring system had the highest specificity for diagnosing ICC and reduced the number of HCC cases diagnosed as LR-M category.

The value of contrast-enhanced magnetic resonance imaging for diagnosis of extrahepatic cholangiocarcinoma

Rationale and objectives

To establish a diagnostic model based on contrast-enhanced magnetic resonance imaging (MRI) and clinical characteristics for diagnosing extrahepatic cholangiocarcinoma (eCCA).

Materials and methods

From April 2014 to September 2021, consecutive patients with extrahepatic bile duct lesions who underwent contrast-enhanced MRI within 1 month before pathological examination were retrospectively enrolled. Two radiologists blinded to clinicopathological information independently evaluated MR images. Univariable and multivariable logistic regression analyses were performed to identify significant clinicoradiological features associated with eCCA, which were subsequently incorporated into a diagnostic model. Model performance was assessed using the area under the receiver operating characteristic curve (AUC), calibration curve, and decision curve.

Results

A total of 182 patients (mean age, 60.8 ± 10.0 years, 117 men) were included, 144 (79 %) of whom had pathologically confirmed eCCA. Diffusion restriction (odds ratio [OR], 8.32; 95 % confidence interval [CI]: 2.88, 25.82; P < 0.001), indistinct outer margin (OR, 4.01; 95 % CI: 1.40, 11.84; P = 0.010), cholelithiasis (OR, 0.34; 95 % CI: 0.12, 1.00; P = 0.049), serum ln(carbohydrate antigen 125) (OR, 4.95; 95 % CI: 1.61, 18.55; P = 0.010), and serum ln(direct bilirubin) (OR, 1.82; 95 % CI: 1.29, 2.63; P < 0.001) were independently associated with eCCA. Incorporating the above 5 variables, a diagnostic model achieved an AUC of 0.912 (95 % CI: 0.859, 0.965), with well-fitted calibration curve (P = 0.815) and good clinical utility. Additionally, the sensitivity, specificity and accuracy of the model were 83.33 %, 86.84 %, and 84.07 %, respectively.

Conclusion

The proposed model integrating two MRI features (i.e., indistinct outer margin and diffusion restriction) and three clinical characteristics (i.e., cholelithiasis, lnCA125 and lnDBIL) enabled accurate diagnosis of eCCA. This tool holds the potential to facilitate an early diagnosis and thereby allow timely treatment interventions and improved clinical outcomes for patients with eCCA.

Diagnostic performance of magnetic resonance imaging and contrast-enhanced ultrasound in differentiating intrahepatic cholangiocarcinoma from hepatocellular carcinoma: a meta-analysis

PURPOSE

To compare the diagnostic ability between magnetic resonance imaging (MRI) and contrast-enhanced ultrasound (CEUS) in distinguishing intrahepatic cholangiocarcinoma (ICC) from hepatocellular carcinoma (HCC).

METHODS

Original studies reporting the diagnostic accuracy of MRI and CEUS in differentiating ICC from HCC were identified in PubMed and EMBASE databases. Histopathological examination was used as the reference standard for tumor diagnosis. Study quality was assessed using QUADAS-2 scale. Data were extracted to calculate the pooled diagnostic sensitivity, specificity, and diagnostic odds ratio (DOR) using a bivariate random-effects model, as well as the area under the curve (AUC). Sensitivity analysis, subgroup analysis, meta-regression, and investigation of publication bias were also performed.

RESULTS

A total of 26 studies with 28 data subsets (18 on MRI, 10 on CEUS) were included, consisting of 4169 patients with 1422 ICC lesions and 2747 HCC lesions. Most MRI studies were performed at 3T with hepatobiliary agents, and most CEUS studies used SonoVue as the contrast agent. In MRI, the pooled sensitivity, specificity, DOR, and AUC in distinguishing ICC from HCC were 0.81 (0.79, 0.84), 0.90 (0.88, 0.91), 41.47 (24.07, 71.44), and 0.93 (0.90, 0.96), respectively. The pooled sensitivity, specificity, DOR, and AUC of CEUS were 0.88 (0.84, 0.90), 0.80 (0.78, 0.83), 42.06 (12.38, 133.23), and 0.93 (0.87, 0.99), respectively. Subgroup analysis and meta-regression analysis demonstrated significant heterogeneity among the studies associated with the type of contrast agent in MRI studies. No publication bias was found.

CONCLUSION

Both MRI and CEUS showed excellent diagnostic performance in differentiating ICC from HCC. CEUS showed higher pooled sensitivity and MRI showed higher pooled specificity.

Safety and feasibility of laparoscopic radical resection for bismuth types III and IV hilar cholangiocarcinoma: a single-center experience from China

Background

Surgery represents the only cure for hilar cholangiocarcinoma (HC). However, laparoscopic radical resection remains technically challenging owing to the complex anatomy and reconstruction required during surgery. Therefore, reports on laparoscopic surgery (LS) for HC, especially for types III and IV, are limited. This study aimed to evaluate the safety and feasibility of laparoscopic radical surgery for Bismuth types III and IV HC.

Methods

The data of 16 patients who underwent LS and 9 who underwent open surgery (OS) for Bismuth types III and IV HC at Mianyang Central Hospital, School of Medicine, University of Electronic Science and Technology of China, between December 2017 and January 2022 were analyzed. Basic patient information, Bismuth-Corlette type, AJCC staging, postoperative complications, pathological findings, and follow-up results were evaluated.

Results

Sixteen patients underwent LS and 9 underwent OS for HC. According to the preoperative imaging data, there were four cases of Bismuth type IIIa, eight of type IIIb, and four of type IV in the LS group and two of type IIIa, four of type IIIb, and three of type IV in the OS group (P>0.05). There were no significant differences in age, sex, ASA score, comorbidity, preoperative percutaneous transhepatic biliary drainage rate, history of abdominal surgery, or preoperative laboratory tests between the two groups (P>0.05). Although the mean operative time and mean intraoperative blood loss were higher in the LS group than in OS group, the differences were not statistically significant (P=0.121 and P=0.115, respectively). Four patients (25%) in the LS group and two (22.2%) in the OS group experienced postoperative complications (P>0.05). No significant differences were observed in other surgical outcomes and pathologic findings between the two groups. Regarding the tumor recurrence rate, there was no difference between the groups (P>0.05) during the follow-up period (23.9 ± 13.3 months vs. 17.8 ± 12.3 months, P=0.240).

Conclusion

Laparoscopic radical resection of Bismuth types III and IV HC remains challenging, and extremely delicate surgical skills are required when performing extended hemihepatectomy followed by complex bilioenteric reconstructions. However, this procedure is generally safe and feasible for hepatobiliary surgeons with extensive laparoscopy experience.

British Society of Gastroenterology guidelines for the diagnosis and management of cholangiocarcinoma

These guidelines for the diagnosis and management of cholangiocarcinoma (CCA) were commissioned by the British Society of Gastroenterology liver section. The guideline writing committee included a multidisciplinary team of experts from various specialties involved in the management of CCA, as well as patient/public representatives from AMMF (the Cholangiocarcinoma Charity) and PSC Support. Quality of evidence is presented using the Appraisal of Guidelines for Research and Evaluation (AGREE II) format. The recommendations arising are to be used as guidance rather than as a strict protocol-based reference, as the management of patients with CCA is often complex and always requires individual patient-centred considerations.

Current state of radiomics in hepatobiliary and pancreatic malignancies

Rising in incidence, hepatobiliary and pancreatic (HPB) cancers continue to exhibit dismal long-term survival. The overall poor prognosis of HPB cancers is reflective of the advanced stage at which most patients are diagnosed. Late diagnosis is driven by the often-asymptomatic nature of these diseases, as well as a dearth of screening modalities. Additionally, standard imaging modalities fall short of providing accurate and detailed information regarding specific tumor characteristics, which can better inform surgical planning and sequencing of systemic therapy. Therefore, precise therapeutic planning must be delayed until histopathological examination is performed at the time of resection. Given the current shortcomings in the management of HPB cancers, investigations of numerous noninvasive biomarkers, including circulating tumor cells and DNA, proteomics, immunolomics, and radiomics, are underway. Radiomics encompasses the extraction and analysis of quantitative imaging features. Along with summarizing the general framework of radiomics, this review synthesizes the state of radiomics in HPB cancers, outlining its role in various aspects of management, present limitations, and future applications for clinical integration. Current literature underscores the utility of radiomics in early detection, tumor characterization, therapeutic selection, and prognostication for HPB cancers. Seeing as single-center, small studies constitute the majority of radiomics literature, there is considerable heterogeneity with respect to steps of the radiomics workflow such as segmentation, or delineation of the region of interest on a scan. Nonetheless, the introduction of the radiomics quality score (RQS) demonstrates a step towards greater standardization and reproducibility in the young field of radiomics. Altogether, in the setting of continually improving artificial intelligence algorithms, radiomics represents a promising biomarker avenue for promoting enhanced and tailored management of HPB cancers, with the potential to improve long-term outcomes for patients.

Results from the european survey on preoperative management and optimization protocols for PeriHilar cholangiocarcinoma

BACKGROUND

Major surgery, along with preoperative cholestasis-related complications, are responsible for the increased risk of morbidity and mortality in perihilar cholangiocarcinoma (pCCA). The aim of the present survey is to provide a snapshot of current preoperative management and optimization strategies in Europe.

METHODS

61 European centers, experienced in hepato-biliary surgery completed a 59-questions survey regarding pCCA preoperative management. Centers were stratified according to surgical caseload (<5 and ≥ 5 cases/year) and preoperative management protocols' application.

RESULTS

The overall case volume consisted of 6333 patients. Multidisciplinary discussion was routinely performed in 91.8% of centers. Most respondents (96.7%) recognized the importance of a well-structured preoperative protocol. The preferred method for biliary drainage was percutaneous transhepatic biliary drainage (60.7%) while portal vein embolization was the preferred technique for liver hypertrophy (90.2%). Differences in preoperative pathologic confirmation of malignancy (35.8% vs 28.7%; p < 0.001), number of mismanaged referred patients (88.2% vs 50.8%; p < 0.001), biliary drainage (65.1% vs 55.6%; p = 0.015) and liver function evaluation (37.2% vs 5.6%; p = 0.001) were found between centers according to groups' stratification.

CONCLUSION

The importance of a correct preoperative management is recognized. Nevertheless, the current lack of guidelines leads to wide heterogeneity of behaviors among centers. This survey can provide recommendations to improve pCCA perioperative outcomes.

Translating imaging traits of mass-forming intrahepatic cholangiocarcinoma into the clinic: From prognostic to therapeutic insights

BACKGROUND & AIMS

The progress toward clinical translation of imaging biomarkers for mass-forming intrahepatic cholangiocarcinoma (MICC) is slower than anticipated. Questions remain on the biologic behaviour underlying imaging traits. We developed and validated imaging-based prognostic systems for resected MICCs with an appraisal of the tumour immune microenvironment (TIME) underpinning patient-specific imaging traits.

METHODS

Between January 2009 and December 2019, a total of 322 patients who underwent dynamic computed tomography/magnetic resonance imaging and curative-intent resection for MICC at three hepatobiliary institutions were retrospectively recruited, divided into training (n = 193) and validation (n = 129) datasets. Two radiological and clinical scoring (RACS) systems, one integrating preoperative variables and one integrating preoperative and postoperative variables, were developed using Cox regression analysis. We then prospectively analysed the TIME of tissue samples from 20 patients who met study criteria from January 2021 to December 2021 using multiplexed immunofluorescence.

RESULTS

Preoperative and postoperative MICC-RACS systems built on carbohydrate antigen 19-9, albumin, tumour number, radiological/pathological nodal status, pathological necrosis, and three radiological traits (arterial enhancement pattern, tumour boundary, and capsular retraction) demonstrated good performance in predicting disease-specific (C-statistic >0.80) and disease-free (C-statistic >0.75) survival that outperformed rival models and staging systems across study cohorts (P <0.05 for all). Patients with MICC-RACS score of 0-2 (low risk), 3-5 (medium risk), and ≥6 (high risk) had incrementally worse prognosis after surgery. Significant differences in spatial distribution and infiltration level of immune cells were identified between arterial enhancement patterns. Enhanced infiltration of immunosuppressive regulatory T cells and M2-like macrophages at the invasive margin were noted in tumours with distinct boundary and capsular retraction, respectively.

CONCLUSIONS

Our MICC-RACS systems are simple but powerful prognostic tools that may facilitate the understanding of spatially distinct TIMEs and patient-tailored immunotherapy approach.

IMPACT AND IMPLICATIONS

The progress toward clinical translation of imaging biomarkers for mass-forming intrahepatic cholangiocarcinoma (MICC) is slower than anticipated. Questions remain on the biologic behaviour of MICC underlying imaging traits. In this study, we proposed novel and easy-to-use tools, built on radiological and clinical features, that demonstrated good performance in predicting the prognosis either before or after surgery and outperformed rival models/systems across major imaging modalities. The characteristic radiological traits integrated into prognostic systems (arterial enhancement pattern, tumour boundary, and capsular retraction) were highly correlated with heterogeneous tumour-immune microenvironments, thereby renovating treatment paradigms for this difficult-to-treat disease.

Response Assessment of Primary Liver Tumors to Novel Therapies: an Imaging Perspective

The latest developments in cancer immunotherapy, namely the introduction of immune checkpoint inhibitors, have led to a fundamental change in advanced cancer treatments. Imaging is crucial to identify tumor response accurately and delineate prognosis in immunotherapy-treated patients. Simultaneously, advances in image acquisition techniques, notably functional and molecular imaging, have facilitated more accurate pretreatment evaluation, assessment of response to therapy, and monitoring for tumor recurrence. Traditional approaches to assessing tumor progression, such as RECIST, rely on changes in tumor size, while new strategies for evaluating tumor response to therapy, such as the mRECIST and the EASL, rely on tumor enhancement. Moreover, the assessment of tumor volume, enhancement, cellularity, and perfusion are some novel techniques that have been investigated. Validation of these novel approaches should rely on comparing their results with those of standard evaluation methods (EASL, mRECIST) while considering the ultimate outcome, which is patient survival. More recently, immunotherapy has been used in the management of primary liver tumors. However, little is known about its efficacy. This article reviews imaging modalities and techniques for assessing tumor response and survival in immunotherapy-treated patients with primary hepatic malignancies.

Prediction of regional lymph node metastasis in intrahepatic cholangiocarcinoma: it's not all about size

OBJECTIVES

Lymph node metastases (LNM) are frequent in patients with intrahepatic cholangiocarcinoma (iCC) and worsen their prognosis even after surgery. Our aim was to investigate the predictive value of lymph node (LN) short axis, the most common discriminator for identifying LNM in tumor-imaging and to develop a predictive model for regional LNM in iCC taking computed tomography (CT) features of extranodal disease into account.

MATERIALS AND METHODS

We enrolled 102 patients with pathologically proven iCC who underwent CT prior to hepatic resection and hilar lymph node dissection (LND) from 2005 to 2021. Two blinded radiologists assessed various imaging characteristics and LN diameters, which were analyzed by bivariate and multivariate logistic regression to develop a prediction model for LNM.

RESULTS

Prevalence of LNM was high (42.4 %) and estimated survival was shorter in LN-positive patients (p = 0.07). An LN short axis diameter of ≥ 9 mm demonstrated the highest predictive power for LNM. Three additional, statistically significant imaging features, presence of intrahepatic metastasis (p = 0.003), hilar tumor infiltration (p = 0.003), and tumor growth along the liver capsule (p = 0.004), were integrated into a prediction model, which substantially outperformed use of LN axis alone in ROC analysis (AUC 0.856 vs 0.701).

CONCLUSIONS

LN diameter alone proved to be a relevant but unreliable imaging-marker for LNM prediction in iCC. Our proposed prognostic model, which additionally considers intrahepatic metastases and hilar and capsular infiltration, significantly improves discriminatory power. Hilar and capsular involvement might indicate direct tumor extension to lymphatic liver structures.

Comparison Between Contrast-Enhanced Computed Tomography and Contrast-Enhanced Magnetic Resonance Imaging With Magnetic Resonance Cholangiopancreatography for Resectability Assessment in Extrahepatic Cholangiocarcinoma

OBJECTIVE

To compare the diagnostic performance and interobserver agreement between contrast-enhanced computed tomography (CECT) and contrast-enhanced magnetic resonance imaging (CE-MRI) with magnetic resonance cholangiopancreatography (MRCP) for evaluating the resectability in patients with extrahepatic cholangiocarcinoma (eCCA).

MATERIALS AND METHODS

This retrospective study included treatment-naïve patients with pathologically confirmed eCCA, who underwent both CECT and CE-MRI with MRCP using extracellular contrast media between January 2015 and December 2020. Among the 214 patients (146 males; mean age ± standard deviation, 68 ± 9 years) included, 121 (56.5%) had perihilar cholangiocarcinoma. R0 resection was achieved in 108 of the 153 (70.6%) patients who underwent curative-intent surgery. Four fellowship-trained radiologists independently reviewed the findings of both CECT and CE-MRI with MRCP to assess the local tumor extent and distant metastasis for determining resectability. The pooled area under the receiver operating characteristic curve (AUC), sensitivity, and specificity of CECT and CE-MRI with MRCP were compared using clinical, surgical, and pathological findings as reference standards. The interobserver agreement of resectability was evaluated using Fleiss kappa (κ).

RESULTS

No significant differences were observed between CECT and CE-MRI with MRCP in the pooled AUC (0.753 vs. 0.767), sensitivity (84.7% [366/432] vs. 90.3% [390/432]), and specificity (52.6% [223/424] vs. 51.4% [218/424]) (P > 0.05 for all). The AUC for determining resectability was higher when CECT and CE-MRI with MRCP were reviewed together than when CECT was reviewed alone in patients with discrepancies between the imaging modalities or with indeterminate resectability (0.798 [0.754-0.841] vs. 0.753 [0.697-0.808], P = 0.014). The interobserver agreement for overall resectability was fair for both CECT (κ = 0.323) and CE-MRI with MRCP (κ = 0.320), without a significant difference (P = 0.884).

CONCLUSION

CECT and CE-MRI with MRCP showed no significant differences in the diagnostic performance and interobserver agreement in determining the resectability in patients with eCCA.

Differential diagnosis of hepatocellular carcinoma and intrahepatic cholangiocarcinoma based on spatial and channel attention mechanisms

BACKGROUND

The pre-operative non-invasive differential diagnosis of hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC) mainly depends on imaging. However, the accuracy of conventional imaging and radiomics methods in differentiating between the two carcinomas is unsatisfactory. In this study, we aimed to establish a novel deep learning model based on computed tomography (CT) images to provide an effective and non-invasive pre-operative differential diagnosis method for HCC and ICC.

MATERIALS AND METHODS

We retrospectively investigated the CT images of 395 HCC patients and 99 ICC patients who were diagnosed based on pathological analysis. To differentiate between HCC and ICC we developed a deep learning model called CSAM-Net based on channel and spatial attention mechanisms. We compared the proposed CSAM-Net with conventional radiomic models such as conventional logistic regression, least absolute shrinkage and selection operator regression, support vector machine, and random forest models.

RESULTS

With respect to differentiating between HCC and ICC, the CSAM-Net model showed area under the receiver operating characteristic curve (AUC) values of 0.987 (accuracy = 0.939), 0.969 (accuracy = 0.914), and 0.959 (accuracy = 0.912) for the training, validation, and test sets, respectively, which were significantly higher than those of the conventional radiomics models (0.736-0.913 [accuracy = 0.735-0.912], 0.602-0.828 [accuracy = 0.647-0.818], and 0.638-0.845 [accuracy = 0.618-0.849], respectively. The decision curve analysis showed a high net benefit of the CSAM-Net model, which suggests potential efficacy in differentiating between HCC and ICC in the diagnosis of liver cancers.

CONCLUSIONS

The proposed CSAM-Net model based on channel and spatial attention mechanisms provides an effective and non-invasive tool for the differential diagnosis of HCC and ICC on CT images, and has potential applications in diagnosis of liver cancers.

Contrast-Enhanced Imaging in the Management of Intrahepatic Cholangiocarcinoma: State of Art and Future Perspectives

Intrahepatic cholangiocarcinoma (iCCA) represents the second most common liver cancer after hepatocellular carcinoma, accounting for 15% of primary liver neoplasms. Its incidence and mortality rate have been rising during the last years, and total new cases are expected to increase up to 10-fold during the next two or three decades. Considering iCCA's poor prognosis and rapid spread, early diagnosis is still a crucial issue and can be very challenging due to the heterogeneity of tumor presentation at imaging exams and the need to assess a correct differential diagnosis with other liver lesions. Abdominal contrast-enhanced computed tomography (CT) and magnetic resonance imaging (MRI) plays an irreplaceable role in the evaluation of liver masses. iCCA's most typical imaging patterns are well-described, but atypical features are not uncommon at both CT and MRI; on the other hand, contrast-enhanced ultrasound (CEUS) has shown a great diagnostic value, with the interesting advantage of lower costs and no renal toxicity, but there is still no agreement regarding the most accurate contrastographic patterns for iCCA detection. Besides diagnostic accuracy, all these imaging techniques play a pivotal role in the choice of the therapeutic approach and eligibility for surgery, and there is an increasing interest in the specific imaging features which can predict tumor behavior or histologic subtypes. Further prognostic information may also be provided by the extraction of quantitative data through radiomic analysis, creating prognostic multi-parametric models, including clinical and serological parameters. In this review, we aim to summarize the role of contrast-enhanced imaging in the diagnosis and management of iCCA, from the actual issues in the differential diagnosis of liver masses to the newest prognostic implications.

Imaging of Hepatobiliary Cancer

The liver and biliary tree are common sites of primary and secondary malignancies. MRI followed by CT is the mainstay for the imaging characterization of these malignancies with the dynamically acquired contrast enhanced phases being the most important for diagnosis. The liver imaging reporting and data system classification provides a useful framework for reporting lesions in patents with underlying cirrhosis or who are at high risk for developing hepatocellular carcinoma. Detection of metastases is improved with the use of liver specific MRI contrast agents and diffusion weighted sequences. Aside from hepatocellular carcinoma, which is often diagnosed noninvasively, other primary hepatobiliary tumors may require biopsy for definite diagnosis, especially when presenting with nonclassic imaging findings. In this review, we examine the imaging findings of common and less common hepatobiliary tumors.