Different MR features for differentiation of intrahepatic mass-forming cholangiocarcinoma from hepatocellular carcinoma according to tumor size

Clinical value and applicability of radiomics in differential diagnosis of dual-phenotype hepatocellular carcinoma and intrahepatic cholangiocarcinoma

BACKGROUND

Dual-phenotype hepatocellular carcinoma (HCC) is a relatively new subtype of HCC. Studies have shown that in the context of chronic hepatitis, liver cirrhosis, and other liver conditions, some intrahepatic cholangiocarcinomas (ICCs) exhibit an enhancement pattern similar to that of HCC. Both dual-phenotype HCC (DPHCC) and ICC can express biliary markers, making imaging and pathology differentiation difficult. Currently, radiomics is widely used in the differentiation, clinical staging, and prognosis assessment of various diseases. Radiomics can effectively differentiate DPHCC and ICC preoperatively.

AIM

To evaluate the value of radiomics in the differential diagnosis of DPHCC and ICC and to validate its clinical applicability

METHODS

In this retrospective study, the data of 53 DPHCC patients and 124 ICC patients were collected retrospectively and randomly divided into training and testing sets at a ratio of 7: 3. After delineation of regions of interest and feature extraction and selection, radiomics models were constructed. Receiver operating characteristic curve analysis was conducted to calculate the area under the curve (AUC) for each model. The AUC values of radiologists with and without assistance from the model were also assessed.

RESULTS

In the training set, the AUC value of the radiomic model was the highest, and the combined model and the radiomic model had similar AUC (P > 0.05); the differences in the AUC values between the combined model and the clinical-sign model was statistically significant (P < 0.05). In the testing set, the AUC value of the combined model was the highest, and the differences in the AUC values between the combined model and the clinical-sign model was statistically significant (P < 0.05). With model assistance, the AUC values of Doctor D (10 years of experience in abdominal imaging diagnosis) and Doctor E (5 years of experience in abdominal imaging diagnosis) both increased.

CONCLUSION

Radiomics can differentiate DPHCC and ICC, and with assistance from the developed model, the accuracy of less experienced doctors in the differential diagnosis of these two diseases can be improved.

Assessment of intrahepatic cholangiocarcinoma with LI-RADS in the high-risk population: MRI diagnosis and postoperative survival

BACKGROUND

The precise impact of LI-RADS-defined risk factors on the diagnosis and prognosis of intrahepatic cholangiocarcinoma (iCCA) remains unclear.

OBJECTIVE

To assess the value of LI-RADS categories and features for iCCA diagnosis, focusing on the diagnostic and prognostic implications of LI-RADS-defined risk factors.

METHODS

Totally 214 high risk patients, including 107 surgically-confirmed solitary iCCAs and 107 hepatocellular carcinomas (HCC) from two centers were retrospectively enrolled. Clinical and MRI features based on LI-RADS v2018 were compared, and the performance of targetoid features for discriminating iCCA was evaluated. Recurrence-free survival (RFS) was compared across different pathologic diagnoses and LI-RADS categories. Multivariate Cox analysis was performed to identify the independent risk factors for RFS.

RESULTS

In the LI-RADS defined high-risk patients, iCCAs differed from HCCs in MRI manifestation. The LR-M category enabled the accurate classification of most iCCAs (89/107, 83.2%), achieving high sensitivity (83.2%), specificity (85.1%), and accuracy (84.1%). The optimal diagnostic performance for iCCA was achieved when at least one targetoid appearance was required for LR-M categorization (AUC = 0.828). Although 26.2% iCCAs presented at least one major feature and 15.0% iCCAs were miscategorized as probably or definitely HCC, only one iCCA case was categorized as LR-5. RFS varied according to both pathologic diagnosis (P = 0.030) and LI-RADS category (P = 0.028), with LI-RADS category demonstrating an independent association with RFS (HR = 1.736, P = 0.033).

CONCLUSIONS

In high-risk patients, iCCAs frequently exhibit HCC major features, leading to miscategorization as probable HCC. However, the LR-5 category remains highly specific for ruling out iCCA. Furthermore, in high-risk patients with solitary resected iCCA or HCC, LI-RADS category enables the prediction of postsurgical prognosis independently from pathological diagnosis.

How to differentiate between combined hepatocellular carcinoma-cholangiocarcinoma and intrahepatic cholangiocarcinoma with rim arterial phase hyperenhancement?

PURPOSE

To analyze and compare the differences in MRI features between combined hepatocellular carcinoma-cholangiocarcinoma (cHCC-CCA) and intrahepatic cholangiocarcinoma (iCCA) with arterial phase peripheral enhancement, so as to provide valuable references for preoperative differential diagnosis.

METHODS

Seventy cHCC-CCA patients and 74 iCCA patients confirmed by pathology were included in this study. Their contrast-enhanced MRI showed rim arterial phase hyperenhancement (Rim APHE). The differences of clinicopathological data and MRI features between cHCC-CCA and iCCA were compared. Then, the sensitivity, specificity, and area under curve (AUC) were also analyzed and compared.

RESULTS

Seventy cHCC-CCA patients (mean age, 55.7 ± 10.6 years) and 74 iCCA patients (mean age, 61.1 ± 10.5 years) were evaluated. In this study, univariable and multivariable regression analysis showed that AFP > 20 ng/ml (OR = 5.824, p = 0.006), enhancing capsule (OR = 7.252, p = 0.001), and mosaic architecture (OR = 32.732, p < 0.001) were independent risk factors of cHCC-CCA with Rim APHE. However, only hepatic capsule retraction (OR = 0.091, p < 0.001) was an independent predictor of iCCA. In addition, combining AFP > 20 ng/ml with enhancing capsule (96.7% vs. 79.2%, p < 0.001) and/or mosaic architecture (96.4% vs. 94.7%, p < 0.001) can improve the sensitivity of differentiating cHCC-CCA (vs. iCCA) with Rim APHE.

CONCLUSION

The combination of elevated AFP and MRI features, such as enhancing capsule and mosaic architecture, will help in preoperative differential diagnosis of cHCC-CCA and iCCA with Rim APHE.

Imaging features and management of focal liver lesions

Notably, the number of incidentally detected focal liver lesions (FLLs) has increased dramatically in recent years due to the increased use of radiological imaging. The diagnosis of FLLs can be made through a well-documented medical history, physical examination, laboratory tests, and appropriate imaging methods. Although benign FLLs are more common than malignant ones in adults, even in patients with primary malignancy, accurate diagnosis of incidental FLLs is of utmost clinical significance. In clinical practice, FLLs are frequently evaluated non-invasively using ultrasound (US), computed tomography (CT), and magnetic resonance imaging (MRI). Although US is a cost-effective and widely used imaging method, its diagnostic specificity and sensitivity for FLL characterization are limited. FLLs are primarily characterized by obtaining enhancement patterns through dynamic contrast-enhanced CT and MRI. MRI is a problem-solving method with high specificity and sensitivity, commonly used for the evaluation of FLLs that cannot be characterized by US or CT. Recent technical advancements in MRI, along with the use of hepatobiliary-specific MRI contrast agents, have significantly improved the success of FLL characterization and reduced unnecessary biopsies. The American College of Radiology (ACR) appropriateness criteria are evidence-based recommendations intended to assist clinicians in selecting the optimal imaging or treatment option for their patients. ACR Appropriateness Criteria Liver Lesion-Initial Characterization guideline provides recommendations for the imaging methods that should be used for the characterization of incidentally detected FLLs in various clinical scenarios. The American College of Gastroenterology (ACG) Clinical Guideline offers evidence-based recommendations for both the diagnosis and management of FLL. American Association for the Study of Liver Diseases (AASLD) Practice Guidance provides an approach to the diagnosis and management of patients with hepatocellular carcinoma. In this article, FLLs are reviewed with a comprehensive analysis of ACR Appropriateness Criteria, ACG Clinical Guideline, AASLD Practice Guidance, and current medical literature from peer-reviewed journals. The article includes a discussion of imaging methods used for the assessment of FLL, current recommended imaging techniques, innovations in liver imaging, contrast agents, imaging features of common nonmetastatic benign and malignant FLL, as well as current management recommendations.

MRI for Hepatitis B-Associated Intrahepatic Cholangiocarcinoma: A Multicenter Comparative Study

BACKGROUND

The diagnosis of intrahepatic cholangiocarcinoma (iCCA) is challenging in hepatitis B virus (HBV)-infected patients, due to the overlapping clinical manifestations and atypical imaging patterns compared to patients without HBV.

PURPOSE

To investigate the preoperative imaging characteristics of iCCA in patients with HBV in comparison to those without HBV.

STUDY TYPE

Retrospective.

SUBJECTS

431 patients with histopathologically confirmed iCCA (143 HBV-positive and 288 HBV-negative patients) were retrospectively enrolled from three institutes, and patients were allocated to the training (n = 302) and validation (n = 129) cohorts from different institutes or time period; 100 matching HBV-positive hepatocellular carcinoma (HCC) patients were also enrolled.

FIELD STRENGTH/SEQUENCE

1.5-T and 3-T, including T1- and T2-weighted, diffusion-weighted and dynamic gadopentetate dimeglumine-enhanced imaging.

ASSESSMENT

Clinical and MRI features were analyzed and compared between HBV-positive and HBV-negative patients with iCCA, and between HBV-positive patients with iCCA and HCC.

STATISTICAL TESTS

Univariate and multivariate logistic regression analyses with odds ratio (OR) to identify independent features for discriminating HBV-associated iCCA. Diagnostic model generation by incorporating independent features, and the performance for discrimination was evaluated by receiver operating characteristics with the area under the curve (AUC) and 95% confidence interval (CI). AUCs were compared by the DeLong's method. A P-value <0.05 was considered statistically significant.

RESULTS

Compared to patients without HBV, washout or degressive enhancement pattern (OR = 51.837), well-defined tumor margin (OR = 8.758) and no peritumoral bile duct dilation (OR = 4.651) were independent significant features for discriminating HBV-associated iCCAs. All these features were also the predominant MRI manifestations for HBV-associated HCC. The combined index showed an AUC of 0.798 (95% CI 0.748-0.842) in the training cohort and an AUC of 0.789 (95% CI 0.708-0.856) in the validation cohort for discrimination. The sensitivity, specificity, and accuracy were all >70%, which was superior to each single feature alone in both cohorts. [Correction added after first online publication on 29 June 2023. The Field Strength/Sequence has been updated from 5-T to 1.5-T.] DATA CONCLUSION: Preoperative MRI may help to discriminate HBV-associated iCCA.

EVIDENCE LEVEL

3 TECHNICAL EFFICACY STAGE: 2.

Dual-phenotype hepatocellular carcinoma: correlation of MRI features with other primary hepatocellular carcinoma and differential diagnosis

Objectives

Dual-phenotype hepatocellular carcinoma (DPHCC) is a rare subtype of hepatocellular carcinoma characterized by high invasiveness and a poor prognosis. The study aimed to compare clinical and magnetic resonance imaging (MRI) features of DPHCC with that of non-DPHCC and intrahepatic cholangiocarcinoma (ICC), exploring the most valuable features for diagnosing DPHCC.

Methods

A total of 208 cases of primary liver cancer, comprising 27 DPHCC, 113 non-DPHCC, and 68 ICC, who undergone gadoxetic acid-enhanced MRI, were enrolled in this study. The clinicopathologic and MRI features of all cases were summarized and analyzed. Univariate and multivariate logistic regression analyses were conducted to identify the predictors. Kaplan-Meier survival analysis was used to evaluate the 1-year and 2-year disease-free survival (DFS) and overall survival (OS) rates in the cohorts.

Results

In the multivariate analysis, the absence of tumor capsule (P = 0.046; OR = 9.777), persistent enhancement (P = 0.006; OR = 46.941), arterial rim enhancement (P = 0.011; OR = 38.211), and target sign on DWI image (P = 0.021; OR = 30.566) were identified as independently significant factors for distinguishing DPHCC from non-DPHCC. Serum alpha-fetoprotein (AFP) >20 μg/L (P = 0.036; OR = 67.097) and hepatitis B virus (HBV) positive (P = 0.020; OR = 153.633) were independent significant factors for predicting DPHCC compared to ICC. The 1-year and 2-year DFS rates for patients in the DPHCC group were 65% and 50%, respectively, whereas those for the non-DPHCC group were 80% and 60% and for the ICC group were 50% and 29%, respectively. The 1-year and 2-year OS rates for patients in the DPHCC group were 74% and 60%, respectively, whereas those for the non-DPHCC group were 87% and 70% and for the ICC group were 55% and 37%, respectively. Kaplan-Meier survival analysis revealed significant differences in the 1-year and 2-year OS rates between the DPHCC and non-DPHCC groups (P = 0.030 and 0.027) as well as between the DPHCC and ICC groups (P = 0.029 and 0.016).

Conclusion

In multi-parameter MRI, combining the assessment of the absence of tumor capsule, persistent enhancement, arterial rim enhancement, and target sign on DWI image with clinical data such as AFP >20 μg/L and HBV status may support in the diagnosis of DPHCC and differentiation from non-DPHCC and ICC. Accurate preoperative diagnosis facilitates the selection of personalized treatment options.

A multi-center diagnostic system for intrahepatic mass-forming cholangiocarcinoma based on preoperative MRI and clinical features

OBJECTIVES

To establish a non-invasive diagnostic system for intrahepatic mass-forming cholangiocarcinoma (IMCC) via decision tree analysis.

METHODS

Totally 1008 patients with 504 pathologically confirmed IMCCs and proportional hepatocellular carcinomas (HCC) and combined hepatocellular cholangiocarcinomas (cHCC-CC) from multi-centers were retrospectively included (internal cohort n = 700, external cohort n = 308). Univariate and multivariate logistic regression analyses were applied to evaluate the independent clinical and MRI predictors for IMCC, and the selected features were used to develop a decision tree-based diagnostic system. Diagnostic efficacy of the established system was calculated by the receiver operating characteristic curve analysis in the internal training-testing and external validation cohorts, and also in small lesions  ≤ 3 cm.

RESULTS

Multivariate analysis revealed that female, no chronic liver disease or cirrhosis, elevated carbohydrate antigen 19-9 (CA19-9) level, normal alpha-fetoprotein (AFP) level, lobulated tumor shape, progressive or persistent enhancement pattern, no enhancing tumor capsule, targetoid appearance, and liver surface retraction were independent characteristics favoring the diagnosis of IMCC over HCC or cHCC-CC (odds ratio = 3.273-25.00, p < 0.001 to p = 0.021). Among which enhancement pattern had the highest weight of 0.816. The diagnostic system incorporating significant characteristics above showed excellent performance in the internal training (area under the curve (AUC) 0.971), internal testing (AUC 0.956), and external validation (AUC 0.945) cohorts, as well as in small lesions  ≤ 3 cm (AUC 0.956).

CONCLUSIONS

In consideration of the great generalizability and clinical efficacy in multi-centers, the proposed diagnostic system may serve as a non-invasive, reliable, and easy-to-operate tool in IMCC diagnosis, providing an efficient approach to discriminate IMCC from other HCC-containing primary liver cancers.

CLINICAL RELEVANCE STATEMENT

This study established a non-invasive, easy-to-operate, and explainable decision tree-based diagnostic system for intrahepatic mass-forming cholangiocarcinoma, which may provide essential information for clinical decision-making.

KEY POINTS

• Distinguishing intrahepatic mass-forming cholangiocarcinoma (IMCC) from other primary liver cancers is important for both treatment planning and outcome prediction. • The MRI-based diagnostic system showed great performance with satisfying generalization ability in the diagnosis and discrimination of IMCC. • The diagnostic system may serve as a non-invasive, easy-to-operate, and explainable tool in the diagnosis and risk stratification for IMCC.

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.

Diagnostic Value of MRI Features in Dual-phenotype Hepatocellular Carcinoma: A Preliminary Study

This study aimed to explore the magnetic resonance imaging (MRI) features of dual-phenotype hepatocellular carcinoma (DPHCC) and their diagnostic value.The data of 208 patients with primary liver cancer were retrospectively analysed between January 2016 and June 2021. Based on the pathological diagnostic criteria, 27 patients were classified into the DPHCC group, 113 patients into the noncholangiocyte-phenotype hepatocellular carcinoma (NCPHCC) group, and 68 patients with intrahepatic cholangiocarcinoma (ICC) were classified into the ICC group. Two abdominal radiologists reviewed the preoperative MRI features by a double-blind method. The MRI features and key laboratory and clinical indicators were compared between the groups. The potentially valuable MRI features and key laboratory and clinical characteristics for predicting DPHCC were identified by univariate and multivariate analyses, and the odds ratios (ORs) were recorded. In multivariate analysis, tumour without capsule (P = 0.046, OR = 9.777), dynamic persistent enhancement (P = 0.006, OR = 46.941), and targetoid appearance on diffusion-weighted imaging (DWI) (P = 0.021, OR = 30.566) were independently significant factors in the detection of DPHCC compared to NCPHCC. Serum alpha-fetoprotein (AFP) > 20 µg/L (P = 0.036, OR = 67.097) and prevalence of hepatitis B virus (HBV) infection (P = 0.020, OR = 153.633) were independent significant factors in predicting DPHCC compared to ICC. The differences in other tumour marker levels and imaging features between the groups were not significant. In MR enhanced and diffusion imaging, tumour without capsule, persistent enhancement and DWI targetoid findings, combined with AFP > 20 µg/L and HBV infection-positive laboratory results, can help to diagnose DPHCC and differentiate it from NCPHCC and ICC. These results suggest that clinical, laboratory and MRI features should be integrated to construct an AI diagnostic model for DPHCC.

A multivariate model based on gadoxetic acid-enhanced MRI using Li-RADS v2018 and other imaging features for preoperative prediction of dual‑phenotype hepatocellular carcinoma

OBJECTIVE

To investigate the diagnostic value of liver imaging reporting and data system (LI-RADS) v2018 and other imaging features in dual-phenotype hepatocellular carcinoma (DPHCC), establish a prediagnostic model based on gadoxetic acid-enhanced MRI, and explore the prognostic significance after surgery of the DPHCC.

MATERIALS AND METHODS

Preoperative enhanced MRI findings and the clinical and pathological data of patients with surgically confirmed HCC were analysed retrospectively. Image analysis was based on LI-RADS v2018 and other image features. Univariate analysis was used to screen for predictive factors of DPHCC, and multivariate logistic regression analysis was used to determine the predictive factors. A regression diagnostic model was established. Receiver operating characteristic (ROC) curve analysis was used to determine the critical value, area under curve (AUC), and the corresponding 95% confidence interval (95% CI). The diagnostic performance was verified by fivefold cross-validation. Cox regression analysis was used to determine the prognostic factors associated with early recurrence after surgical resection.

RESULTS

In total, 158 patients were included, of whom 79 had DPHCC and 79 had non-DPHCC. Multivariate analysis showed that rim arterial phase hyperenhancement (Rim APHE) and targetoid restriction were independent risk factors for DPHCC (P < 0.05). The AUC (95% CI) of the model was 0.862 (0.807-0.918), sensitivity was 81.01%, and specificity was 89.874%. Cox regression analysis showed that DPHCC, microvascular invasion, tumour diameter, and an increase of alpha-fetoprotein were independent factors for recurrence.

CONCLUSION

Rim APHE and targetoid restriction were sensitive imaging features of DPHCC before surgery, and the identification of DPHCC has important prognostic significance for early recurrence.

A nomogram based on ultrasonographic features and clinical indicators for differentiating mass-forming intrahepatic cholangiocarcinoma and liver metastatic colorectal adenocarcinoma

OBJECTIVE

This study aimed to develop and validate a nomogram based on ultrasonographic features and clinical indicators to differentiate mass-forming intrahepatic cholangiocarcinoma (MF-ICC) from hepatic metastatic colorectal adenocarcinoma.

MATERIALS AND METHODS

A total of 343 patients with pathologically confirmed MF-ICC or metastatic colorectal adenocarcinoma were enrolled between October 2018 and July 2022. Patients were randomly assigned to training and validation sets at a ratio of 7:3. Preoperative ultrasound features and clinical indicators were retrieved. Univariate logistic regression analysis was employed to select relevant features. Multivariate logistic regression analysis was used to establish a predictive model, which was presented as a nomogram in training sets. The model's performance was assessed in terms of discrimination, calibration, and clinical usefulness.

RESULTS

The study included 169 patients with MF-ICC and 174 with liver metastatic colorectal adenocarcinoma, assigned to training (n=238) and validation (n=105) cohorts. The nomogram incorporated ultrasound features (tumor size, lesion number, echogenicity, tumor necrosis, and rim arterial phase hyperenhancement) and clinical information (serum levels of CEA, CA19-9, CA125). The nomogram demonstrated promising performance in differentiating these two entities in both training and validation sets, with an AUC value of 0.937 (95%CI: 0.907,0.969) and 0.916 (95%CI: 0.863,0.968), respectively. The Hosmer-Lemeshow test and calibration curves confirmed good consistency between predictions and observations. Additionally, decision curve analysis confirmed the nomogram's high clinical practicability.

CONCLUSION

The nomogram based on ultrasound features and clinical indicators demonstrated good discrimination performance in differentiating MF-ICC from metastatic colorectal adenocarcinoma, which may enhance clinical decision-making process in managing these challenging diagnostic scenarios.

Preoperative prediction of cytokeratin-19 expression for hepatocellular carcinoma using T1 mapping on gadoxetic acid-enhanced MRI combined with diffusion-weighted imaging and clinical indicators

Objectives

To explore the value of T1 mapping on gadoxetic acid-enhanced magnetic resonance imaging (MRI) in preoperative predicting cytokeratin 19 (CK19) expression for hepatocellular carcinoma (HCC).

Methods

This retrospective study included 158 patients from two institutions with surgically resected treatment-native solitary HCC who underwent preoperative T1 mapping on gadoxetic acid-enhanced MRI. Patients from institution I (n = 102) and institution II (n = 56) were assigned to training and test sets, respectively. univariable and multivariable logistic regression analyses were performed to investigate the association of clinicoradiological variables with CK19. The receiver operating characteristic (ROC) curve and precision-recall (PR) curve were used to evaluate the performance for CK19 prediction. Then, a prediction nomogram was developed for CK19 expression. The performance of the prediction nomogram was evaluated by its discrimination, calibration, and clinical utility.

Results

Multivariable logistic regression analysis showed that AFP>400ng/ml (OR=4.607, 95%CI: 1.098-19.326; p=0.037), relative apparent diffusion coefficient (rADC)≤0.71 (OR=3.450, 95%CI: 1.126-10.567; p=0.030), T1 relaxation time in the 20-minute hepatobiliary phase (T1rt-HBP)>797msec (OR=4.509, 95%CI: 1.301-15.626; p=0.018) were significant independent predictors of CK19 expression. The clinical-quantitative model (CQ-Model) constructed based on these significant variables had the best predictive performance with an area under the ROC curve of 0.844, an area under the PR curve of 0.785 and an F1 score of 0.778. The nomogram constructed based on CQ-Model demonstrated satisfactory performance with C index of 0.844 (95%CI: 0.759-0.908) and 0.818 (95%CI: 0.693-0.902) in the training and test sets, respectively.

Conclusions

T1 mapping on gadoxetic acid-enhanced MRI has good predictive efficacy for preoperative prediction of CK19 expression in HCC, which can promote the individualized risk stratification and further treatment decision of HCC patients.

Holistic management of hepatocellular carcinoma: The hepatologist's comprehensive playbook

Hepatocellular carcinoma (HCC) is a common complication in patients with chronic liver disease and leads to significant morbidity and mortality. Liver disease and liver cancer are preventable by mitigating and managing common risk factors, including chronic hepatitis B and C infection, alcohol use, diabetes, obesity and other components of the metabolic syndrome. The management of patients with HCC requires treatment of the malignancy and adequate control of the underlying liver disease, as preserving liver function is critical for successful cancer treatment and may have a relevant prognostic role independent of HCC management. Hepatologists are the ideal providers to guide the care of patients with HCC as they are trained to identify patients at risk, apply appropriate surveillance strategies, assess and improve residual liver function, evaluate candidacy for transplant, provide longitudinal care to optimize and preserve liver function during and after HCC treatment, survey for cancer recurrence and manage its risk factors, and prevent and treat decompensating events. We highlight the need for a team-based holistic approach to the patient with liver disease and HCC and identify necessary gaps in current care and knowledge.

Combined Hepatocellular-Cholangiocarcinoma: An Update on Pathology and Diagnostic Approach

Combined hepatocellular-cholangiocarcinoma (cHCC-CCA) is a rare primary liver carcinoma displaying both hepatocytic and cholangiocytic differentiation within the same tumor. Relative to classic hepatocellular carcinoma (HCC), cHCC-CCA has more aggressive behavior and a poorer prognosis. Though recent advances have improved our understanding of the biology underlying cHCC-CCAs, they remain diagnostically challenging for pathologists because of their morphologic and phenotypic diversity. Accurate diagnosis of cHCC-CCA is important for patient management and prognostication. Herein, we review recent updates on cHCC-CCA, focusing on tumor classification, pathology, and diagnostic approach.

Utility of mean platelet volume in differentiating intrahepatic cholangiocarcinoma from hepatocellular carcinoma

Background

Intrahepatic cholangiocarcinoma (ICC) and hepatocellular carcinoma (HCC) are the most prevalent histologic types of primary liver cancer. HCC and ICC differ in treatment and prognosis, warranting an effective differential diagnosis between them. This study aimed to explore the clinical value of mean platelet volume (MPV) to discriminate between HCC and ICC.

Material/methods

We performed a retrospective analysis of ICC and HCC patients who were from the Harbin Medical University Cancer Hospital, China. Logistic regression analysis was used to identify the independent factors for the differentiation of HCC and ICC. A receiver operating characteristic curve was built to evaluate the diagnostic performance of the potential model. An independent validation study was performed to validate the diagnostic ability.

Results

ICC patients were detected in 146 out of 348 patients in the primary cohort. MPV levels were decreased in ICC patients compared with those in HCC patients. Logistic regression analysis revealed that MPV was an independent factor in distinguishing HCC from ICC. A combination of sex, hepatitis B surface antigen, MPV, alpha-fetoprotein, and carbohydrate antigen 19–9 demonstrated a good capability to differentiate HCC from ICC. Similar results were achieved in the validation cohort.

Conclusions

MPV may be a new marker to help distinguish ICC from HCC. Further validation studies are required.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-022-02348-0.

MR Features Based on LI-RADS Ver. 2018 Correlated with Cytokeratin 19 Expression in Combined Hepatocellular Carcinoma-Cholangiocarcinoma

Purpose

To investigate the significance of MR features based on the Liver Imaging Reporting and Data System (LI-RADS ver. 2018) for identifying the expression of cytokeratin 19 (CK-19) in patients with combined hepatocellular carcinoma-cholangiocarcinoma (cHCC-CCA) before surgery.

Patients and Methods

The study enrolled 174 patients pathologically confirmed to have cHCC-CCA according to the 2019 WHO classification. The preoperative MR imaging features and clinicopathological findings were retrospectively evaluated and compared between the CK-19-positive and CK-19-negative cHCC-CCA groups.

Results

One hundred seventy-four patients (mean age, males vs females: 56.6 ± 10.0 years vs 54.7 ± 14.2 years) were evaluated. The presence of mosaic architecture, targetoid appearance, cholangiectasis, hepatic capsule retraction, and corona enhancement was significantly higher in the CK-19-positive group (all p < 0.05), while nonrim arterial phase hyperenhancement (APHE) was more common in the CK-19-negative group (p = 0.04). The univariate analysis showed that hepatitis B virus infection, CEA > 5 ng/mL, tumor size, nonrim APHE, mosaic architecture, targetoid appearance, cholangiectasis, hepatic capsule retraction, and corona enhancement were significant risk factors for CK-19-positive cHCC-CCA (all p < 0.05). Unfortunately, the multivariate analysis revealed that only corona enhancement (OR = 2.359, p = 0.03) was an independent risk factor associated with CK-19-positive cHCC-CCA.

Conclusion

Corona enhancement is significantly correlated with CK-19 positivity in patients with cHCC-CCA.

Magnetic Resonance Imaging of Nonhepatocellular Malignancies in Chronic Liver Disease

Hepatocellular carcinoma (HCC) is the most common liver malignancy associated with chronic liver disease. Nonhepatocellular malignancies may also arise in the setting of chronic liver disease. The imaging diagnosis of non-HCC malignancies may be challenging. Non-HCC malignancies in patients with chronic liver disease most commonly include intrahepatic cholangiocarcinoma and combined hepatocellular-cholangiocarcinoma, and less commonly hepatic lymphomas and metastases. On MR imaging, non-HCC malignancies often demonstrate a targetoid appearance, manifesting as rim arterial phase hyperenhancement, peripheral washout, central delayed enhancement, and peripheral restricted diffusion. When applying the Liver Imaging Reporting and Data System algorithm, observations with targetoid appearance are categorized as LR-M.

Preoperative Prediction of Cytokeratin 19 Expression for Hepatocellular Carcinoma with Deep Learning Radiomics Based on Gadoxetic Acid-Enhanced Magnetic Resonance Imaging

Purpose

Cytokeratin 19 (CK19) expression is a proven independent prognostic predictor of hepatocellular carcinoma (HCC). This study aimed to develop and validate the performance of a deep learning radiomics (DLR) model for CK19 identification in HCC based on preoperative gadoxetic acid-enhanced magnetic resonance imaging (MRI).

Patients and Methods

A total of 141 surgically confirmed HCCs with preoperative gadoxetic acid-enhanced MRI from two institutions were included. Prediction models were established based on hepatobiliary phase (HBP) images using a training set (n=102) and validated using time-independent (n=19) and external (n=20) test sets. A receiver operating characteristic curve was used to evaluate the performance for CK19 prediction. Recurrence-free survival (RFS) was also analyzed by incorporating the CK19 expression and other factors.

Results

For predicting CK19 expression, the area under the curve (AUC) of the DLR model was 0.820 (95% confidence interval [CI]: 0.732–0.907, P<0.001) with sensitivity, specificity, accuracy of 0.800, 0.766, and 0.775, respectively, and reached 0.781 in the external test set. Combined with alpha fetoprotein, the AUC increased to 0.833 (95% CI: 0.753–0.912, P<0.001) and the sensitivity was 0.960. Intratumoral hemorrhage and peritumoral hypointensity on HBP were independent risk factors for HCC recurrence by multivariate analysis. Based on predicted CK19 expression and the independent risk factors, a nomogram was developed to predict RFS and achieved C-index of 0.707.

Conclusion

This study successfully established and verified an optimal DLR model for preoperative prediction of CK19-positive HCCs based on gadoxetic acid-enhanced MRI. The prediction of CK19 expression in HCC using a non-invasive method can help inform preoperative planning.

Role of 3D quantitative tumor analysis for predicting overall survival after conventional chemoembolization of intrahepatic cholangiocarcinoma

This study was designed to assess 3D vs. 1D and 2D quantitative tumor analysis for prediction of overall survival (OS) in patients with Intrahepatic Cholangiocarcinoma (ICC) who underwent conventional transarterial chemoembolization (cTACE). 73 ICC patients who underwent cTACE were included in this retrospective analysis between Oct 2001 and Feb 2015. The overall and enhancing tumor diameters and the maximum cross-sectional and enhancing tumor areas were measured on baseline images. 3D quantitative tumor analysis was used to assess total tumor volume (TTV), enhancing tumor volume (ETV), and enhancing tumor burden (ETB) (ratio between ETV and liver volume). Patients were divided into low (LTB) and high tumor burden (HTB) groups. There was a significant separation between survival curves of the LTB and HTB groups using enhancing tumor diameter (p = 0.003), enhancing tumor area (p = 0.03), TTV (p = 0.03), and ETV (p = 0.01). Multivariate analysis showed a hazard ratio of 0.46 (95%CI: 0.27–0.78, p = 0.004) for enhancing tumor diameter, 0.56 (95% CI 0.33–0.96, p = 0.04) for enhancing tumor area, 0.58 (95%CI: 0.34–0.98, p = 0.04) for TTV, and 0.52 (95%CI: 0.30–0.91, p = 0.02) for ETV. TTV and ETV, as well as the largest enhancing tumor diameter and maximum enhancing tumor area, reliably predict the OS of patients with ICC after cTACE and could identify ICC patients who are most likely to benefit from cTACE.

Liver Imaging and Data System (LI-RADS) Version 2018 and Other Imaging Features in Intrahepatic Cholangiocarcinoma in Chinese Adults with vs. without Chronic Hepatitis B Viral Infection

PURPOSE

To describe liver imaging reporting and data system (LI-RADS) version 2018 and other MRI imaging features in intrahepatic mass-forming cholangiocarcinoma (iCCA) in Chinese adults with vs. without chronic hepatitis B viral (HBV) infection.

METHODS

We retrospectively enrolled 89 patients with pathologically proven iCCA after multiphase imaging performed between 2004 and 2017 at a tertiary medical center in southern China. Based on whether patients had chronic HBV, iCCA was divided into two subgroups: HBV-positive (n = 50 patients, including 9 with cirrhosis) vs. HBV-negative (n = 39 patients, including 14 with hepatolithiasis and 25 with no identifiable risk factor for iCCA; none had cirrhosis). Two independent abdominal radiologists in consensus reviewed the largest mass in each patient to assign LI-RADS v2018 features; they also scored each observation's shape and location. Imaging features were compared using chi-square or Fisher's exact tests.

RESULTS

Most iCCAs in HBV-positive (88% (44/50)) and HBV-negative (97% (38/39)) patients had at least one LR-M feature. Compared to iCCAs in HBV-negative patients, iCCAs in HBV-positive patients were more likely to have at least one major feature of HCC (46% (23/50) vs. 8% (3/39), P < 0.001) and more likely to be smooth (42% (21/50) vs. 10% (4/39), P = 0.001). Six of 50 (12%) iCCAs in HBV-positive patients and 1/39 (3%) iCCAs in HBV-negative patients had at least one major feature of HCC without any LR-M feature.

CONCLUSIONS

In this retrospective single-center study in Chinese adults, iCCAs in HBV-positive patients were more likely to resemble HCCs than iCCAs in HBV-negative patients.

Focal intrahepatic strictures: A proposal classification based on diagnosis-treatment experience and systemic review

BACKGROUND

Focal intrahepatic strictures (FIHS) refer to local strictures of the small and medium intrahepatic bile ducts. FIHS are easily misdiagnosed due to their rare incidence, and few studies have focused on the diagnosis and treatment approaches.

AIM

To propose a new classification for FIHS in order to guide its diagnosis and treatment.

METHODS

The symptoms, biochemistry results, imaging results, endoscopic examination results and initial and final diagnoses of 6 patients with FIHS admitted between January 2010 and December 2019 were retrospectively analyzed.

RESULTS

The 6 patients were diagnosed with intratubular growth-type intrahepatic cholangiocarcinoma (IG-ICC), recurrent multiple hepatocellular carcinoma (rmHCC) with bile duct tumor thrombus (BDTT), adenosquamous carcinoma (ASC), hepatolithiasis, small duct primary sclerosing cholangitis (SD-PSC) and autoimmune hepatitis (AIH). The initial and final diagnoses were not consistent in 4 patients. Hepatectomy was performed in patients with IG-ICC, ASC and hepatolithiasis according to the locations of their FIHS. Patients with rmHCC with BDTT received lenvatinib/sintilimab, while patients with SD-PSC and AIH received UDCA. We proposed the following classification system for FIHS: type I: FIHS located within one segment of the liver; type II: FIHS located at the confluence of the bile ducts of one segment or two adjacent segments; type III: FIHS connected to the left or right hepatic duct; and type IV: Multiple FIHS located in both lobes of the liver.

CONCLUSION

Our proposed classification system might help to guide the diagnosis and treatment of FIHS. Hepatectomy should be performed not only for malignant FIHS but also for benign strictures with severe secondary damage that cannot be improved by nonsurgical methods.

Hepatic nodules with arterial phase hyperenhancement and washout on enhanced computed tomography/magnetic resonance imaging: how to avoid pitfalls

This essay aimed to illustrate the various hepatic nodules that may exhibit arterial phase hyperenhancement and washout on computed tomography/magnetic resonance imaging (CT/MRI). Hepatic nodules with arterial phase hyperenhancement and washout on CT/MRI include hepatocellular carcinoma, focal nodular hyperplasia-like nodules, serum amyloid A-positive hepatocellular neoplasms, intrahepatic cholangiocarcinoma, intrahepatic bile duct adenoma, hepatoblastoma, hepatocellular adenoma, hepatic epithelioid angiomyolipoma, and metastasis including neuroendocrine and gastrointestinal stromal tumors. Understanding the imaging findings is important to ensure correct diagnosis.

A Contemporary Approach to Diagnosis and Treatment of Combined Hepatocellular-Cholangiocarcinoma

Purpose of review

To provide updates on terminology, epidemiology, diagnosis, and treatment of combined hepatocellular-cholangiocarcinoma (cHCC-CCA).

Recent findings

cHCC-CCAs are tumors that in the same nodule contain a variable degree of HCC and CCA components with a transition zone. cHCC-CCAs develop in cirrhotic and non-cirrhotic livers like and is associated with poor outcomes. Mutations in TP53, TERT promoter, and ARID1A are the most common genetic aberrations in cHCC-CCA. Fusion gene PTMS-AP1G1 is unique for cHCC-CCA. A biopsy is required for diagnosis. Surgical resection remains treatment of choice, while liver transplantation for early cHCC-CCA is associated with favorable outcomes. Gemcitabine-based therapy shows benefits for advanced cHCC-CCA.

Summary

cHCC-CCAs are a heterogeneous group of primary liver cancers with unique biological behavior. Multicenter studies are required for a molecular analysis to inform novel therapeutic approaches, and understand epidemiology and benefits of liver transplantation, liver-directed and targeted therapies for this rare aggressive cancer.

Evaluation of Primary Liver Cancers Using Hepatocyte-Specific Contrast-Enhanced MRI: Pitfalls and Potential Tips

When radiologists interpret hepatic focal lesions seen on dynamic magnetic resonance imaging (MRI) scans, it is important not only to distinguish malignant lesions from benign ones but also to distinguish nonhepatocellular carcinoma (HCC) malignancies from HCCs. In addition, most major guidelines, including those of the American Association for the Study of Liver Disease, European Association for the Study of the Liver, and Korean Liver Cancer Association and National Cancer Center, allow for the noninvasive imaging diagnosis of HCC in at-risk patients. However, ~40% of HCC cases show atypical imaging features mimicking non-HCC malignancies. Furthermore, several benign and malignant lesions, such as flash-filling hemangioma and intrahepatic mass-forming cholangiocarcinoma, frequently look like HCC. In contrast, although multiparametric MRI options, including hepatobiliary phase and diffusion-weighted imaging, provide useful information that could help address these challenges, there remain several unresolved issues with regard to the noninvasive diagnostic criteria characterizing HCC. In this article, we discuss the typical imaging features and challenging situations related to primary liver cancers in MRI, while considering how to make a correct diagnosis. LEVEL OF EVIDENCE: 5 TECHNICAL EFFICACY STAGE: 3.

User and system pitfalls in liver imaging with LI-RADS

The Liver Imaging Reporting and Data System (LI-RADS) is a comprehensive system for standardizing the terminology, technique, interpretation, reporting, and data collection of liver imaging, created specifically for patients at risk for hepatocellular carcinoma. Over the past years, LI-RADS has been progressively implemented into clinical practice, but pitfalls remain related to user error and inherent limitations of the system. User pitfalls include the inappropriate application of LI-RADS to a low-risk patient population, incorrect measurement techniques, inaccurate assumptions about LI-RADS requirements, and improper usage of LI-RADS terminology and categories. System pitfalls include areas of discordance with the Organ Procurement and Transplantation Network (OPTN) as well as pitfalls related to rare ancillary features. This article reviews common user pitfalls in applying LI-RADS v2018 and how to avoid preventable errors and also highlights deficiencies of the current version of LI-RADS and how it might be improved in the future. Level of Evidence:3 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019. J. Magn. Reson. Imaging 2019;50:1673-1686.

Cholangiocarcinoma

Cholangiocarcinoma is a rare malignancy and accounts for 2% of all malignancies. Incidence is on the increase in the Western world. Cholangiocarcinoma arises from the malignant growth of the epithelial lining of the bile ducts and can be found all along the biliary tree. It can be classified into subtypes based on location: intrahepatic (arising from the intrahepatic biliary tract in the hepatic parenchyma), perihilar (at the hilum of the liver involving the biliary confluence) and distal (extrahepatic, often in the head of the pancreas). Margin status and locoregional lymph node metastases are the most important determinants of postsurgical outcomes.