RPS 1016 - Radiologic advances in hepatobiliary and pancreatic cancer

Author Block: B. Song, F. Che; Chengdu/CN
Purpose: This study aimed to assess the potential role of 3-dimensional (3D) fractal dimension (FD) derived from contrast-enhanced computed tomography (CT) images in predicting microvascular invasion (MVI) in hepatocellular carcinoma (HCC) patients.
Methods or Background: This retrospective study included 655 patients with surgically confirmed HCC from two medical centers (training set: 406 patients; internal test set: 170 patients; external test set: 79 patients). Box-counting algorithms were employed to compute the 3D FD values from portal venous phase images. Univariable and multivariable logistic regression analyses were used to determine independent clinical and imaging predictors. Diagnostic performance of the model was assessed using receiver operating characteristic (ROC) curve analysis. Recurrence-free survival (RFS) and overall survival (OS) curves were generated via Kaplan-Meier method and compared using the log-rank test.
Results or Findings: Patients with MVI-positive HCC exhibited significantly higher FD values compared to those with MVI-negative HCC (P< 0.01). The combined model, integrating alpha-fetoprotein level, tumor size, number, and FD, demonstrated superior diagnostic performance for MVI prediction compared to the clinical model alone, with AUCs of 0.80 (95% CI: 0.75, 0.88) and 0.75 (95% CI: 0.67, 0.83) for the internal test set, and 0.83 (95% CI: 0.72, 0.92) and 0.74 (95% CI: 0.61, 0.85) for the external test set. Patients predicted to have high-risk MVI showed worse RFS and OS outcomes than those predicted to have low-risk MVI (all P<0.05).
Conclusion: The 3D FD value significantly differed between MVI-positive and MVI-negative HCC patients. Integration of FD into the clinical model enhances MVI prediction accuracy and may identify patients at high risk.
Limitations: Firstly, the retrospective nature of our study introduces inherent limitations. Secondly, our study only analyzed 3D fractal features on the PVP phase.
Funding for this study: None
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: Institutional Review Board approval was obtained by West China Hospital and Henan Provincial People’s Hospital

Author Block: H. Y. Chen, B-B. Chen; Taipei/TW
Purpose: This study aims to evaluate the impact of pretreatment body composition, assessed via CT or MRI, on the likelihood of achieving conversion surgery and overall survival (OS) in pancreatic cancer patients undergoing neoadjuvant therapy (NAT).
Methods or Background: A retrospective analysis was conducted on 154 patients with pancreatic cancer receiving NAT before planned conversion surgery between May, 2018 and February, 2024. Clinical and laboratory data, including carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA19-9), were collected. Body composition parameters such as skeletal muscle volume (SM), skeletal muscle index, subcutaneous adipose tissue (SAT), and visceral adipose tissue (VAT) at the L3 vertebral level were automatically calculated using the TotalSegmentator software. Independent predictors of conversion surgery were identified using multivariable logistic regression, and Kaplan-Meier curves and Cox regression models assessed the impact of these variables on OS.
Results or Findings: Patients who underwent conversion surgery group had significantly smaller tumor sizes (P=0.033), lower rates of vascular invasion (P=0.042), lower log-transformed CA19-9 levels (P=0.002), higher SM (P=0.049), and higher VAT (P=0.048). Multivariate analysis revealed that log-transformed CA19-9 (P=0.002) and higher SM (P=0.049) were independent predictors of conversion surgery. Conversion surgery (P<0.001) and higher SAT (P=0.001) were associated with better OS. SAT was identified as an independent predictor of OS (P=0.04) after adjusting for age, conversion surgery status, and TNM stage in the multivariate model.
Conclusion: Pretreatment body composition, as evaluated through imaging, may be associated with the feasibility of conversion surgery and overall survival in patients with pancreatic cancer receiving NAT. Specifically, higher skeletal muscle volume and SAT appear to be favorable prognostic factors, highlighting the importance of body composition in clinical decision-making and patient outcomes.
Limitations: The limitations of the study are single center study and relatively small patient group.
Funding for this study: No funding was received for this study
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: Research Ethics Committee of National Taiwan University Hospital

Author Block: A. Celestino, P. Marra, A. Barbaro, C. Gargiulo, R. Muglia, G. Muscogiuri, P. A. Bonaffini, S. Sironi; Bergamo/IT
Purpose: The LI-RADS classification is universally employed for hepatocellular carcinoma (HCC) risk stratification of liver nodules in cirrhosis, but it relies on a qualitative evaluation. This study aims to investigate the potential role of material density (MD) parameters in the iodine maps of Spectral Computed Tomography (SCT), to discriminate between LI-RADS categories in cirrhotic patients, therefore increasing the radiologists’ confidence in LI-RADS class allocation.
Methods or Background: Dual-energy SCT scans of cirrhotic patients with nodules between March 2022 and September 2023 were retrospectively reviewed. All the images were reviewed by trained radiologists to classify nodules as LI-RADS 3, 4 or 5 by consensus. MD maps were generated in the hepatic arterial phase (HAP), portal venous (PVP) and equilibrium phase (EP). Iodine concentration density (ICD) of nodules (ICDnodule) and non-nodular liver parenchyma (ICDliver) were measured to calculate lesion-to-non-nodular liver ICD ratio (LNR), their differences (ΔICD) and ratios (rLNR). Results were correlated with LI-RADS categories.
Results or Findings: 69 patients were included and 79 DECT exams were examined. 197 nodules (size 24.67 ± 23.11 mm, mean ± SD) were categorised under different LI-RADS classes, as follows: 44 as LI-RADS 3 (22.3%), 14 as LI-RADS 4 (7.1%), and 139 as LI-RADS 5 (70.6%). Arterial LNR, arterial ICDnodule, ΔICD and rLNR between HAP and PVP could discriminate between LI-RADS 3 and LI-RADS 4+5 nodules (p < 0.001). All the calculated MD parameters showed similar, or slightly higher diagnostic accuracy rates (all AUCs = 70-73%) compared to those previously reported by non-spectral CT (up to 70%).
Conclusion: MD parameters of liver nodules measured in SCT scans are viable diagnostic tools that may increase the radiologist’s confidence in LI-RADS class allocation in cirrhotic patients.
Limitations: The lack of an adequate number of LI-RADS 4 nodules
Funding for this study: None
Has your study been approved by an ethics committee? Not applicable
Ethics committee - additional information: None

Author Block: S. Rau¹, T. Stein¹, A. Rau¹, C. Wilpert¹, F. B. Pallasch¹, B. Bogner¹, S. Faby², J. Weiß¹; ¹Freiburg/DE, ²Forchheim/DE
Purpose: To evaluate image quality and diagnostic accuracy of photon-counting detector (PCD) computed tomography (CT) for the detection of PCLs compared to conventional energy-integrating detector (EID) CT with MRI serving as reference standard.
Methods or Background: In this prospective study, we included consecutive patients who underwent clinically indicated contrast-enhanced PCD-CT of the abdomen and for whom an additional abdominal EID-CT was available. Multiparametric MRI served as the reference standard. CT images were assessed for the presence of PCLs by three radiologists independently in a blinded reading. In addition, image quality, lesion conspicuity, and diagnostic confidence were rated on a 5-point Likert scale (5=excellent). The coefficient-of-variation (CV) and the density difference (in Hounsfield units [HU]) between PCLs and visually normal pancreatic parenchyma were calculated as quantitative imaging measures. Radiation dose was assessed using CTDIvol [mGy].
Results or Findings: Among 106 included patients (age 62.7±12.6 years; 45 [42.5%] male), 46 had MRI-confirmed cystic lesions (mean size 8.7±7.4mm; range: 2-45 mm). Diagnostic accuracy for PCLs was significantly higher for PCD-CT vs. EID-CT (area under the curve: 0.81 vs. 0.74; p=0.002; sensitivity: 76.8% vs. 59.4%; specificity 84.4% vs. 88.3%, respectively). Image quality, lesion conspicuity and diagnostic confidence were rated superior for PCD-CT vs. EID-CT (all p<0.001). Quantitative analyses revealed a significantly lower CV (0.19 vs. 0.24; p=0.002) and a higher density difference (94.1 HU vs. 76.6 HU p<0.001) between PCLs and visually normal pancreatic parenchyma at lower radiation doses (7.13 vs. 8.68 mGy; p<0.001) for PCD-CT vs. EID-CT.
Conclusion: PCD-CT provided significantly higher diagnostic accuracy and superior image quality for the detection of PCLs compared to conventional EID-CT at lower radiation dose.
Limitations: No long-term follow-up and/or histopathological correlation of the detected PCLs were omitted.
Funding for this study: None
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: The local Institutional Review Board (Ethics Committee of the University Medical Center Freiburg, case number 21-2469) approved this prospective study and written informed consent was obtained from all patients prior to study inclusion.

Author Block: M. Dupuis, A. Dupont, S. Pizza, V. Vilgrain, A. Bando Delaunay, R. Lebtahi, M. Bouattour, M. Ronot, J. Gregory; Clichy/FR
Purpose: This study evaluates the prognostic value of tumor response at three months on CT, assessed by RECIST, mRECIST, and LI-RADS Treatment Response Algorithm (LR-TRA) in patients with hepatocellular carcinoma (HCC) treated with selective internal radiation therapy (SIRT).
Methods or Background: A retrospective analysis was conducted on 102 HCC patients treated with SIRT between 2018 and 2020. RECIST, mRECIST, and LR-TRA were assessed at 3 months post-SIRT. Overall survival (OS) and progression-free survival (PFS) were assessed using Kaplan-Meier analysis and Cox proportional hazards models.
Results or Findings: Median age was 71 years, most patients (90%) had advanced-stage tumors (BCLC-C). After a median follow-up of 32.0 months (95% CI: 16.8-60.9), 60/102 patients died (59%), and 90/102 patients showed tumor progression (88%). Median OS was 20.4 months (95% CI: 15.4-33.0), and median PFS was 14.5 months (95% CI: 6.5-24.5); 1-year OS and PFS rates were 65.6% and 50.7%. Multivariable analysis revealed that early response according to RECIST 1.1 (HR 1.66, p=0.30), mRECIST (HR 1.40, p=0.215), and LR-TRA (HR 0.67, p=0.30) were not predictors of OS. Disease progression evaluated by RECIST (HR 2.55, p<0.001) and mRECIST (HR 2.53, p<0.001), bilirubin levels (HR 1.03, p<0.001) and prothrombin time (HR 0.98, p=0.005) were predictors of OS. For PFS, neither RECIST nor mRECIST response, disease progression, nor LR-TRA viability were predictors.
Conclusion: In this advanced-stage HCC population, early response assessed by RECIST, mRECIST, and LR-TRA criteria did not predict OS or PFS after SIRT. However, early disease progression and liver function indicators were prognostic factors for OS.
Limitations: Several limitations exist in this single-center, retrospective study, including a small sample size, which may reduce the generalizability of the findings. Additionally, tumor heterogeneity, a key prognostic-factor for poor treatment response and shorter PFS, was not considered.
Funding for this study: None
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: This single-center retrospective clinical study was approved by the local Institutional Review Board (IRB 00006477), and informed consent was waived due to its retrospective nature.

Author Block: J. Zhou, Y. Li, L. Lii; Guangzhou/CN
Purpose: The sensitivity of Contrast-enhanced ultrasound (CEUS) for diagnosing hepatocellular carcinoma (HCC) is lower than MRI, especially in small liver nodules measuring 20mm or less. This study aimed to compare the diagnostic performance between CEUS with perfluorobutane (P-CEUS) and MRI Liver Imaging Reporting and Data System (LI-RADS) version 2018 (v2018) for small liver nodules in high-risk patients.
Methods or Background: This multi-center retrospective study included high-risk patients with newly detected liver nodules measuring 20mm or less from March 2020 to November 2023. Patients underwent CEUS with perfluorobutance (P-CEUS) and concurrent MRI at intervals of no more than 1 month. The reference standard was pathological confirmation or 24-month imaging follow-up (only for benign lesions). The diagnostic performance of CEUS LI-RADS v2017 for P-CEUS, modified criteria for P-CEUS, and MRI LI-RADS v2018 was calculated and compared. For the modified criteria for P-CEUS, LR-4 observations measuring 10 mm or larger with nonrim APHE and no washout were reclassified as LR-5 if aslo showing a Kupffer defect; LR-M observations measuring 10 mm or larger with nonrim APHE and early washout were reclassified as LR-5 if aslo showing a mild Kupffer defect.
Results or Findings: A total of 367 participants (301 males; mean age, 54±11 years) with 401 observations (mean diameter, 15±4 mm) were included. Using LR-5 for HCC daignosis, MRI LI-RADS v2018 had higher sensitivity (73% vs 57%, P<0.001) with no significant lower specificity (90% vs 94%, P=0.18) compared with CEUS LI-RADS v2017. The modified criteria for P-CEUS and MRI LI-RADS v2018 showed no significant difference (P>0.05) in sensitivity (70% vs 73%) and specificity (92% vs 90%).
Conclusion: CEUS using perfluorobutane with modified criteria demonstrated a diagnostic performance comparable to MRI in HCC diagnosis for small liver nodules (≤20mm).
Limitations: Retrospective study
Funding for this study: This study was not supported by any funding.
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: Approved

Author Block: M. Youssef Francis, T. Broussaud, M. Wagner, J. Benzimra, N. Brillat-Savarin, O. Lucidarme; Paris/FR
Purpose: To investigate whether the use of dual-layer spectral CT (DLSCT) improves the diagnostic accuracy of hepatocellular carcinomas (HCCs) compared with conventional CT.
Methods or Background: 127 patients were included in this retrospective study. All patients underwent multiphase DLSCT (IQon, Philips Healthcare) for the initial diagnosis of HCC. Arterial phase hyperenhancement (APHE) and portal and delayed washout of each lesion were qualitatively assessed by two radiologists independently using three-point Likert scales and the lesion-to-liver contrast-to-noise ratio (LLCNR) was quantified using ROI in conventional (CIs) and 40keV virtual monoenergetic images (VMIs). For qualitative analysis, interobserver agreement was assessed using the kappa statistic. For quantitative analysis, LLCNRs were compared using Wilcoxon and Scheirer-Ray-Hare tests.
Results or Findings: 163 HCCs were independently analyzed. The APHE was considered significantly higher for both observers in VMIs compared to CIs: mean 2.36 vs 1.32 p<0.001. The washout was considered significantly better seen in VMIs compared to CIs in the delayed phase: mean 1.99 vs 1.33, p<0.001; but not in the portal phase: mean 1.74 vs 1.36, NS. Interobserver agreement was good for APHE and washout in both CIs and VMIs. The LLCNR was significantly higher in the arterial phase (6.18vs2.05;p<0.001) and significantly lower in the delayed phase (-2.02 vs -1.10; p<0.001) in 40 Kev-VMIs compared to CIs. As in the subjective analysis, LLCNR was not significantly different in the portal phase (-1.89 vs -1.52;NS).
Conclusion: Multiphasic DLCT with 40 keV VMIs increases the visibility of both APHE and washout in the delayed phase of focal liver lesions compared to CIs, leading to the final diagnosis of a higher number of HCCs.
Limitations: This is a single-center, retrospective study. DLSCT was not compared with MRI, which is currently the gold standard in the detection of HCC.
Funding for this study: No funding was received for this study.
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: This study was IRB approved (number CRM-2304-339).

Author Block: L. Müller¹, R. Kloeckner², L. Heim¹, F. Stoehr¹, F. Hahn¹, T. Bäuerle¹, A. Weinmann¹, D. Pinto Dos Santos³, A. Mähringer-Kunz¹; ¹Mainz/DE, ²Lübeck/DE, ³Frankfurt/DE
Purpose: Low bone mineral density (BMD) has recently emerged as a risk factor in hepatocellular carcinoma (HCC). However, its role in patients with HCC complicated by portal vein tumor thrombosis (PVTT) is unclear. This study explores the potential of BMD as a prognostic indicator within this subgroup, which is characterized by an exceptionally poor prognosis.
Methods or Background: This retrospective study included 462 patients with HCC and PVTT diagnosis at our tertiary care center between January 2005 and December 2020. BMD was measured by mean Hounsfield units (HUs) at the midvertebral core of the first lumbar vertebra in computed tomography using the established cut-off of 160 HU. Analysis was performed at two points in time: initial HCC diagnosis and PVTT onset. We analyzed the impact of BMD on median overall survival (OS) and conducted multivariate analysis with established survival predictors.
Results or Findings: Median BMD was 136 HU (IQR, 113–160 HU) at HCC diagnosis and 134 HU (IQR, 109–159 HU) at PVTT diagnosis. At initial HCC diagnosis, patients with BMD ≥ 160 HU had a median OS of 10.4 months, compared to 5.5 months in those with BMD < 160 HU (p < 0.001). At PVTT diagnosis, those with higher BMD had a median OS of 8.5 months, versus 4.7 months in patients with lower BMD (p < 0.001). BMD remained an independent prognostic factor in multivariate analysis, alongside growth type and ALBI grade.
Conclusion: BMD serves as an independent prognostic marker for survival in patients with HCC and PVTT. Incorporating BMD into existing classification and scoring systems could enhance the accuracy of survival predictions and inform clinical decision-making processes.
Limitations: The primary limitation is the retrospective study design, necessitating validation of these findings in a prospective framework.
Funding for this study: None
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: The study was approved by the responsible ethical body: Ethics committee of the Medical Association of Rhineland Palatinate, Mainz, Germany (Permit number: 15913).

Author Block: D. J. A. D. C. E. Aragão, S. Santos, J. Nobre, L. M. Cabral; Lisboa/PT
Purpose: To retrospectively evaluate a cohort of patients with solid pancreatic lesions who underwent endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA).
To review the radiologic features of common solid pancreatic neoplasms and correlate them with cytopathological findings.
Methods or Background: A retrospective review was performed at our institution, encompassing 100 EUS-FNA procedures during 18 consecutive months. Patients with solid pancreatic lesions or lesions with a solid component (n=48) were included in the analysis. Clinical data, imaging studies, and cytopathology reports were collected. The most illustrative cases were selected to demonstrate the radiologic and cytopathologic characteristics of these neoplasms.
Results or Findings: The most frequently diagnosed solid pancreatic neoplasm was adenocarcinoma (median age: 70 years; 61% male; 71% located in the pancreatic head), typically presenting as a hypovascular mass. Neuroendocrine tumors, often hypervascular, were the second most common neoplasm. Rare cases included one case of pancreatic lymphoma and one case of metastatic disease involving the pancreas.
Conclusion: As expected, pancreatic adenocarcinoma, particularly in elderly males and localized in the pancreatic head, was the most commonly diagnosed neoplasm. EUS-FNA combined with cytopathologic analysis, along with multimodality imaging, remains essential in the accurate diagnosis, staging, and management of solid pancreatic neoplasms. The integration of these diagnostic tools ensures a comprehensive multidisciplinary approach, leading to more effective patient care and treatment planning.
Limitations: No limitations were identified.
Funding for this study: No funding was received for this study.
Has your study been approved by an ethics committee? Not applicable
Ethics committee - additional information: This study is educational.

Author Block: V. Koch¹, M. Cimprich¹, L. D. Grünewald¹, C. Booz¹, T. Vogl¹, O. Darwish², J. Gotta¹, S. Mahmoudi¹, R. Sinkus³; ¹Frankfurt/DE, ²London/UK, ³Paris/FR
Purpose: This study aimed to evaluate 2D/3D magnetic resonance imaging (MRE) utilizing the gravitational transducer concept compared to the current acoustic product solution (2D-MRE Resoundant) to further characterize pancreatic carcinoma and its potential to provide imaging biomarkers for outcome prediction.
Methods or Background: In this prospective study, 40 patients with confirmed pancreatic cancer undergoing MRI of the upper abdomen were enrolled between June 2023 and September 2024. Furthermore, 15 healthy volunteers were included as a healthy reference standard. All participants underwent two examinations using a 40Hz mechanical vibration frequency (Aera 1.5T, Siemens Healthineers, Germany): initially with the acoustic MRE (Resoundant, 2D-MRE, SE-EPI sequence, 11s breath hold [BH]), and subsequently with the gravitational MRE (2D-MRE and 3D-MRE, GRE sequence, TE=9.53ms [in-phase], and fractional motion encoding at 30mT/m, 14s BH). Two experienced readers independently conducted data analysis. Additionally, superimposed analytic plane waves with known properties at various amplitudes and temporal noise levels were employed to investigate biases in stiffness reconstruction (2D/3D) and suggest Quality Indices for 2D/3D.
Results or Findings: Significant differences were observed in stiffness values, shear wave speed, and phase angle between healthy volunteers and patients with pancreatic cancer using both MRE approaches (p<.05). Additionally, patients who showed clinical response to chemotherapy exhibited differences in stiffness (p<.05). However, the Bland-Altman plots exhibited a notable bias, with 2D-MRE tending to overestimate stiffness values. 3D-MRE provided several imaging biomarkers that correlated with disease progression and response to therapy. Proposed Quality Indices enabled the identification of pixels exhibiting a deviation exceeding 10% from actual stiffness values in 3D-MRE.
Conclusion: Gravitational MRE proves to be an accurate technique for noninvasively characterizing pancreatic tissue. In particular, 3D MRE can provide pertinent functional imaging markers, advancing functional abdominal imaging.
Limitations: Single-center study.
Funding for this study: This study has been funded by the Doktor Robert Pfleger Foundation.
Has your study been approved by an ethics committee? Not applicable
Ethics committee - additional information: The institutional ethical review board approved this prospective study. Written informed consent was obtained from all participants.

Author Block: L. Asmundo, L. Giaccardi, A. Soro, C. Buonomenna, R. Vigorito, F. G. Greco, A. Casale, M. Vaiani; Milan/IT
Purpose: Solitary Necrotic Nodule of the Liver (SNNL) is a rare, benign hepatic lesion frequently misdiagnosed as malignant, leading to unnecessary invasive procedures. This study presents a case series of patients diagnosed with SNNL, focusing on their imaging characteristics, clinical management and outcomes.
Methods or Background: This retrospective case series analyzed data from patients diagnosed with SNNL at a tertiary referral center. Collected data included demographics, imaging studies, and follow-up outcomes. A radiologist with 20 years of experience reviewed all imaging studies. The reference standard was histological examination or follow-up imaging
Results or Findings: Among 13 patients (54% female; median age 54 years), MRI was the preferred imaging modality, with 3 to 5 scans performed over a median follow-up of 25 months (range 22-70). SNNL typically presented as a necrotic core surrounded by a fibrotic capsule, often with a nodular, elongated, or C-shaped appearance that mimicked biliary dilatation. T1-weighted images showed isointensity in 53.8% of cases, with hypointensity of the core in 84.6%. T2-weighted images revealed isointensity (38.5%) or hypointensity (61.5%) of the core. Nodules remain hypovascular after contrast media injection. Diffusion-weighted imaging displayed no restricted diffusion. During follow-up, most nodules (92.3%) showed a reduction in size, with increased calcification on CT (from 38.5% to 69.2%).
Conclusion: SNNL presents diagnostic challenges due to its resemblance to aggressive hepatic lesions, particularly cholangiocarcinoma and metastases. However, careful interpretation of MRI and CT findings can prevent unnecessary invasive procedures.
Limitations: The small sample size and single-center design limit the generalizability of the findings. While only a few cases had histological confirmation (30%), long-term imaging follow-up supports the benign nature of SNNL, reducing the need for biopsies and surgeries.
Funding for this study: none. The authors did not receive support from any organization
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: Local ethic committee approved the study protocol