Vietnamese journal of radiology and nuclear medicine

Expert Consensus on the Role of Hepato-Biliary Specific Contrast Agents in the Diagnosis of Hepatocellular Carcinoma

Minh Thong Pham — 2025-09-30

Hepatocellular carcinoma (HCC) remains a major health burden worldwide, including in Vietnam. Current national guidelines rely on dynamic imaging with CT, MRI, or ultrasound for diagnosis; however, detecting early-stage HCC and lesions with atypical imaging features remains challenging. Gadoxetic acid–enhanced MRI (EOB-MRI) offers advantages by combining dynamic vascular assessment with hepatocyte-specific uptake. During the hepatobiliary phase (15–20 minutes post-injection), lesions with impaired transporter function fail to retain contrast and appear hypointense compared with surrounding parenchyma, thereby improving sensitivity for the detection and characterization of early HCC.
On January 26, 2024, a scientific workshop on the use of EOB-MRI in HCC diagnosis was held in Hanoi, organized by the Vietnamese Society of Radiology and Nuclear Medicine with participation from leading experts from Korea and major hospitals across Vietnam. Presentations from radiology, hepatology, and hepatobiliary surgery specialists reached a shared recognition of the clinical value of EOB-MRI. Based on the workshop and supporting international evidence, a draft consensus statement was developed. This document was subsequently revised and finalized at the Society’s Annual Scientific Meeting in August 2024, with contributions from both domestic and international experts. The consensus highlights the pivotal role of EOB-MRI in the diagnosis of HCC and provides recommendations for its clinical application.

Clinical Application of Wses 2020 for the Evaluation of Acute Colonic Diverticulitis

Trong Binh Le

Purpose: To describe the computed tomography (CT) findings of acute colonic diverticulitis (ACD), and to evaluate its complications by using the World Society of Emergency Surgery (WSES) 2020 guideline.
Methods: Data of 70 patients with ACD treated at Hue University of Medicine and Pharmacy Hospital and Hue Central Hospital from 1/2022 to 8/2023 were analyzed. Diagnosis of CD was mainly based on CT while endoscopy and/or surgery were required if CT findings were inconclusive. Clinical manifestations, blood tests, CT findings and treatment methods were documented. Multivariate logistic regression model was run to ascertain predictors of complications of ACD.
Results: The median age was 44 (range, 35-55.3) years old, male/female ratio was 2.68, 80% of ACD was right-sided, and 94.3% of patients had diverticulosis, On CT, 100% of ACD showed fat stranding, 85.7%
colon wall thickening (in which 90% was circumferential thickening), 24.3% pericolic air bubbles, 31.4% pericolic fluid. Abscess formation was seen in 11.4%, abdominal free air in 5.7%, diffuse abdominal fluid in 8.6%, and fistula in 2.9% of cases. According to WSES 2020, the incidence of uncomplicated (stage 0) ACD was 52.9%; and complicated ACD stages 1A, 1B, 2A, 2B, 3, and 4 were 27.1%, 4.3%, 7.1%, 0%, 2.9%, and 5.7%, respectively. Factors related to complications of ACD were smoking, digestive disorders, rebound tenderness, leukocytosis, elevated NEU, CRP and CT findings including loss of diverticular wall continuity, and length of colon wall thickening. Multivariable regression analysis showed that CRP was an independent predictor of ACD complication (OR 1.016; 95% CI 1.002-1.031; p = 0.028). The cut-off value of CRP for prediction was 89.9 mg/L with sensitivity of 69.7%, specificity of 80.6%, area under the curve of 0.797, p < 0.001.
Conclusion: Right-sided ACD is more predominant. Colonic diverticulosis, fat stranding, circumferential colonic wall thickening were common CT findings. The majority of ACD patients were in stages 0 and
1A according to WSES 2020. CRP level >89.9 mg/L was an independent predictor of complications. In patients with suspected ACD who had CRP >89.9 mg/L, CT should be indicated for timely diagnosis and detection of complication.

Evaluation of the Value of ¹⁸F-FDG PET/CT in Identifying Recurrent Breast Cancer Lesions

Van Trung Cao

Objective: To assess the role of ¹⁸F-FDG PET/CT in detecting recurrent lesions in breast cancer patients following curative-intent treatment at K Hospital.
Methods: A cross-sectional descriptive study was conducted on 115 female breast cancer patients who were clinically or paraclinically suspected of recurrence at least six months after completion of curativeintent therapy at K Hospital between November 2021 and December 2023. All participants underwent ¹⁸F-FDG PET/CT for assessment evaluation.
Results: The mean age was 53.7 ± 10.1 years. Invasive ductal carcinoma of no special type comprised 83.5% of cases, and the ERpositive/HER-2-negative phenotype was present in 43.7%. ¹⁸F-FDG PET/
CT yielded a sensitivity of 91.8%, specificity of 93.3%, positive predictive value of 90.9%, negative predictive value of 92.2%, and overall accuracy of 92.2% for recurrence detection. The mean SUVₘₐₓ of recurrent lesions was 10.4 ± 4.7. ROC analysis revealed an AUC of 0.92. Among 56 patients with histopathologically confirmed recurrence, PET/CT detected an additional 28 unsuspected lesions (50%), achieving the highest PPV among all modalities evaluated.
Conclusion: ¹⁸F-FDG PET/CT demonstrates high accuracy in diagnosing recurrent breast cancer compared with other modalities, with SUVₘₐₓ values at readily detectable levels and the capacity to identify
additional lesions.

Initial Treatment Outcomes of Radiofrequency Ablation for Papillary Thyroid Microcarcinoma at Bach Mai Hospital

Van Khang Le

Objective: To evaluate the initial outcomes of radiofrequency ablation (RFA) for the treatment of papillary thyroid microcarcinoma (PTMC) at Bach Mai Hospital.
Methods: A retrospective and prospective cross-sectional descriptive study was conducted on all patients who underwent RFA for PTMC at Bach Mai Hospital between October 1, 2022, and December 31, 2024. All patients were followed for a minimum of 6 months after the procedure.
Results: The study included 32 patients (3 males and 29 females) with a mean age of 44,69 ± 13,42 years (range: 24–75). The mean tumor volume was 0,064 ± 0,079 ml. All patients underwent RFA for PTMC.
The mean follow-up duration was 16,29 ± 8,04 months. The complete disappearance rate of tumors increased over time: 0% at 3 months, 14,3% at 6 months, 31,8% at 12 months, 81,8% at 18 months, and 100% at 24 months of follow-up. Only one patient (3,1%) experienced transient hoarseness; no delayed complications or permanent injuries were observed.
Conclusion: RFA is a minimally invasive, effective, and safe treatment option for PTMC.

Imaging Characteristics of Pulmonary Metastases on Computed Tomography and Outcomes of Radiofrequency Ablation for Local Treatment of Pulmonary Metastases Under Robot Maxio Guidance

Gia Khanh Dinh

Objective: To characterize the imaging features of pulmonary metastases on computed tomography (CT) and to evaluate the outcomes of radiofrequency ablation (RFA) for local treatment of pulmonary
metastases using Maxio robot guidance.
Methods: The study was a combined prospective and retrospective descriptive analysis conducted on 60 patients with pulmonary metastatic lesions, of whom 30 underwent radiofrequency ablation (RFA) under the guidance of the Maxio robotic system at the 108 Military Central Hospital between June 2021 and June 2025
Results: Most patients presented with multiple metastatic nodules rather than solitary ones. The most common sites were the right upper lobe and the lower lobes of both lungs. The mean tumor diameter was 25 ± 4.5 mm. The majority of lesions were solid nodules (86.7%). Radiofrequency ablation (RFA) was performed once in 19 patients, twice in 7 patients, and three times in 4 patients. The disease control rate reached 86.7%, with tumor necrosis observed at 6 months. One case of life-threatening massive hemoptysis was recorded.
Conclusion: Pulmonary metastatic lesions typically present as multiple, solid nodules, commonly located in the lower lobes of both lungs and the right upper lobe. Radiofrequency ablation of pulmonary
metastases under Maxio robotic guidance demonstrated favorable initial efficacy with a low complication rate.

Clinical and Paraclinical Characteristics, and Treatment Outcomes of I-131-Refractory Differentiated Thyroid Cancer at Vietnam National Cancer Hospital

The Tan Nguyen

Objective: This research aim to evaluate clinical, paraclinical characteristics and treatment outcomes in patients with I-131 refractory differentiated thyroid cancer at Vietnam National Cancer Hospital (K
hospital).
Methods: descriptive study on 27 patients with differentiated thyroid cancer, I-131 refractory from January 2020 to October 2023.
Results: The mean age of patient was 50.26 ± 15.5 years old; the female/male ratio was 3/1. Histology: 19 patients (70.4%) were papillary, 07 patients (25.9%) were follicular, 01 patient (3.7%) was papillaryfollicular. The mean of treatment dose until defined I-131 refractory was 396.2 ± 156.7mCi. According to the 2015 ATA I-131 refractory criteria, there were 14 patients (51.9%) in group I (no uptake I-131 at the first WBS), 7 patients ( 25.9%) in group II (the tumor tissue loses the ability to concentrate I-131 after previous evidence of I-131-avid disease), 5 patients (18.5%) in group III (I-131 is concentrated in some lesions but not in others), 01 patient (3.7%) in group IV (metastatic disease progresses despite a significant concentration of I-131). There were 04 patients (14.8%) who received surgery for metastatic lesions, 09 patients (33.3%) received further treatment with I-131, 10 patients (37%) did not receive any treatment and continued to follow monitoring and TSH suppression, the remaining 02 patients (7.4%) received external radiotherapy and treated with Lenvatinib. There were 06 patients (22.2%) achieved complete response, 07 patients (25.9%) achieved biochemical incomplete response, 03 patients (11.1%) achieved unclear response, structural incomplete response in 11 patients (40.7%).
Conclusion: I-131 refractory differentiated thyroid cancer is a new area. Treatment requires a combination of methods and individualization. When the disease is widespread, targeted therapy such as Lenvatinib helps improve survival and alleviate symptoms.

Initial Evaluation of the Safety And Efficacy of Transarterial Chemoembolization in the Management Of Hepatocellular Carcinoma at E Hospital

Kieu Huyen Trang Pham

Objective: To evaluate the safety and initial effectiveness of chemical embolization in the treatment of hepatocellular carcinoma (HCC) and some related factors.
Methods: Cross-sectional retrospective study on 41 patients diagnosed with HCC treated with trans arterial chemoembolisation, followed clinical and paraclinical findings after intervention between April
2024 and May 2025 in Department of Radiology – E Hospital.
Results: the mean participant age was 63.05 ± 10.2 years; 39 were men (95%). The proportion of Child–Pugh A patients was the highest with 40 patients (97.5%); the peak level of AST/ALT 1 week after treatment was 237.2 ± 390.3 UI/L and 259.3 ± 415.1 UI/L for DE B-TACE versus 180 ± 259.5 UI/L and 162.6 ± 206.5 UI/L for cTACE (p >.05). Abdominal pain is the most common symptom following the intervention, with a higher incidence in the DEB-TACE group for tumors < 5 cm (57.1%) compared to 33.3% in the cTACE group. Regarding treatment efficacy, the rate of tumor control after 1 month was good in both DEB-TACE and cTACE groups (92% and 100%, respectively). For tumors <5 cm, the disease control rate (DCR) was better in the cTACE group at 100%. For tumors > 5 cm, the overall response rate (ORR) in the DEB-TACE group (76.5%) was higher compared to cTACE (40%). Additionally, the study showed that for advanced stage BCLC C tumors, the overall response rate (ORR) in the DEB-TACE group was better at 83.3%.
Conclusions: Both DEB-TACE and cTACE have good initial efficacy and safety in treating HCC who were not eligible for curative surgery. For patients with larger tumors and advanced stage (BCLC C),
DEB-TACE demonstrates better efficacy. For patients with smaller tumors, cTACE shows advantages with a higher disease control rate and fewer side effects, particularly when performed using superselective catheterization techniques.

The Value of Apparent Diffusion Coefficient in Determining Gleason Score of Prostate Cancer

Thuy Nga Nguyễn

Objective: Evaluate the correlation and value of apparent diffusion coefficient (ADC) in determining the Gleason score of prostate cancer (PC).
Methods: From January 2023 to December 2024, 39 patients were diagnosed and had histopathological results of PC, who had undergone prostate MRI before. We evaluated the correlation between the ADC
value and the Gleason score using Spearman’s correlation coefficient, then compared the ADC value between two groups of clinical insignificance (Gleason =6) and clinical significance PC (Gleason >6) by using Mann-Whitney U test. The ROC curve was used to find the ADC value in distinguishing clinical insignificance and significance PC.
Results: The average age of patients was 75.8 ± 7.3 years. The mean gland volume was 48.4 ± 25.4 grams. 62% of PC originated from the peripheral region, 38% originated from the central glandular region.
7.7% of patients had a Gleason score = 6, 92.3% of patients had a Gleason score > 6. The ADC value at the lesion was strongly negatively correlated with the Gleason score, with Spearman’s correlation coefficient = -0.619 (p = 0.000). The mean ADC value of the Gleason =6 group was 1194.33 ± 41.9 s/mm2, statistically higher than that of the Gleason >6 group at 802.3 ± 115.4 s/mm2 (p <0.05). ROC curve analysis showed that with an ADC threshold of 1093.5 s/mm2, diffusion MRI was able to differentiate clinically insignificant and significant PC with a sensitivity of 100% and a specificity of 97.2%.
Conclusion: ADC values were significantly correlated with Gleason scores and were able to predict clinically insignificant and significant PC.

The Value of Computed Tomography in the Diagnosis of Adnexal Torsion

Ho Vu Khoi Nguyen

Objective: To determine the diagnostic value of computed tomography (CT) in detecting adnexal torsion.
Methods: A retrospective, case-control study was conducted, including 110 surgical cases involving the adnexa, among which 55 cases were confirmed to have adnexal torsion. CT imaging findings
were recorded and analyzed using the Chi-square test, receiver operating characteristic (ROC) curve analysis, and multivariate logistic regression to assess diagnostic value and develop a diagnostic model for adnexal torsion.
Results: Adnexal torsion predominantly occurred in patients under 50 years old and was more frequently found on the right side. Malignant histopathological results accounted for approximately 8,9%. The CT
features associated with adnexal torsion included eccentric wall thickening, whirlpool sign, mass sign, navel sign, crescent sign, hemorrhage, uterine deviation, and non-enhancing tissue (p < 0,05). Among these, the whirlpool sign showed the highest specificity and positive predictive value in diagnosing adnexal torsion (96,4% and 93,6%, respectively). The diagnostic model for adnexal torsion based on four key features –whirlpool sign, mass sign, non-enhancing tissue, and navel sign – demonstrated good performance, with an area under the curve (AUC) of 0,88, sensitivity of 83,6%, and specificity of 89,3%.
Conclusion: CT is a valuable imaging modality for diagnosing adnexal torsion. The diagnostic model based on four key features –whirlpool sign, mass sign, non-enhancing tissue, and pedicle sign –
provides significant support in diagnosing the condition.

Initial Results of Safety and Efficacy of Artificial Ascites - Assisted Thermal Ablation of Hepatocellular Carcinoma at High Risk Location

Tan Tai Nguyen

Introduction: Primary hepatocellular carcinoma (HCC) is a common malignancy worldwide with high mortality. Thermal ablation is a potentially curative therapy, but ultrasound-guided ablation of tumors in
high-risk locations is often limited by poor visualization and risk of thermal injury to adjacent organs. Artificial ascites offers a simple and effective solution to improve safety. This study evaluated the efficacy, safety, local recurrence, and clinical outcomes of artificial ascites-assisted thermal ablation for high-risk HCC.
Methods: We conducted a retrospective case series of patients diagnosed with HCC in high-risk sites who underwent thermal ablation with artificial ascites assistance.
Results: A total of 12 patients with hepatocellular carcinoma underwent thermal ablation. The mean age was 66.5 ± 9.07 years (range, 49–79), with a male-to-female ratio of 2:1. Of these, seven patients were
treated with microwave ablation and five with radiofrequency ablation. The mean distance between the tumor and critical adjacent organs was 4.25 ± 2.73 mm (range, 1–8 mm). Artificial ascites was successfully created via a 6F angiosheath in all cases (technical success rate: 100%), with a mean infused volume of 1054.2 ± 423.97 ml (range, 500–2000 ml). No major complications occurred following the procedure.
Conclusion: Artificial ascites-assisted thermal ablation is a safe and effective approach for treating primary HCC in high-risk locations, reducing the risk of collateral injury and improving treatment feasibility.

Comparison of Left Atrial Volume, Left Atrial Appendage Volume, and Epicardial Adipose Tissue Volume Between Patients with Paroxysmal and Persistent Atrial Fibrillation

Thi Thao Nguyen

Objective: This study aimed to evaluate differences in left atrial volume (LAV), left atrial appendage volume (LAAV), and epicardial fat volume (EFV) between patients with paroxysmal atrial fibrillation (PAF)
and persistent atrial fibrillation (PersAF), while analyzing the association of these factors with disease progression.
Methods: A cross-sectional study was conducted on 58 AF patients undergoing radiofrequency ablation, who underwent cardiac multidetector computed tomography (MDCT) at Bach Mai Hospital from January 2024 to May 2025. Left atrial, left atrial appendage, and epicardial fat volumes were measured using Syngo.via software.
Results: The study included 58 AF patients (72.4% PAF, 27.6% PersAF) with a mean age of 60.5 ± 9.2 years, revealing significant anatomical differences. The PersAF group had significantly larger LAV (126.6 ± 51.0
ml vs. 83.4 ± 19.6 ml, p < 0.001) and LAAV (18.3 ± 9.7 ml vs. 12.7 ± 6.2 ml, p = 0.004) compared to the PAF group. Multivariate regression analysis adjusted for confounders confirmed that PersAF independently increased LAV by 22.5 ml (95% CI 13.1–31.9, p < 0.001) and LAAV by 4.25 ml (95% CI 0.16–8.34, p= 0.041). Notably, although initial differences in EFV and left atrial–specific EFV (LA-EFV) were observed (p < 0.05), these became non-significant after adjustment (EFV: β = 6.3, p = 0.166; LA-EFV: β = 2.4, p = 0.093). Independent predictors of increased EFV and LA-EFV included male sex, higher BMI, and hypertension (p < 0.05). These findings provide evidence of cardiac remodeling in PersAF and suggest a complex pathogenesis involving anatomical and metabolic factors.
Conclusion: The study confirms significant differences in LAV and LAAV between PAF and PersAF patients. However, the association between epicardial fat volume and AF subtype remains unclear, warranting
further investigation.

Management of Non-Mass Enhancement on Breast MRI: Diagnostic Challenges and Clinical Strategies

Thu Huong Nguyen

Non-mass enhancement (NME) on breast magnetic resonance imaging (MRI) is a diagnostically challenging entity that can be easily confused with background parenchymal enhancement and physiological
changes. This article provides an overview of the concept, imaging features, and diagnostic challenges of NME according to BI-RADS, while also analyzing clinical management strategies based on multimodality
correlation and histopathological results. Sources include the American College of Radiology Breast Imaging Reporting and Data System (ACR BI-RADS, 5th edition, 2013), recent international studies, and illustrative clinical cases from local practice. The article highlights the role of risk stratification (BI-RADS 3, 4a, 4b), indications for MRI-guided biopsy versus alternative modalities such as ultrasound and mammography, as well as the value of short-term follow-up in reducing unnecessary biopsies. Future research prospects focus on refining grading criteria for NME and standardizing MRI-guided biopsy protocols. In conclusion, the management of NME requires a comprehensive approach, taking into account clinical context and individual risk factors to optimize diagnostic accuracy and treatment outcomes.

Radioactive Iodine-Refractory Differentiated Thyroid Cancer with Brain Metastasis: A Clinical Case Report

Le Thanh Hai Nguyen

Background: Differentiated thyroid cancer (DTC) is mainly treated with surgery and radioactive iodine (RAI), and typically has a favorable prognosis. Cases with distant metastasis often have a poorer prognosis and are at risk of becoming resistant to radioactive iodine. Progressive radioactive iodine-refractory DTC with brain metastasis is extremely rare and carries a grave prognosis, requiring a multimodal treatment approach. This report describes a typical clinical case, emphasizing diagnostic and therapeutic strategies.
Case Description: A 65-year-old female patient, diagnosed with papillary thyroid carcinoma, underwent total thyroidectomy and received four RAI treatments (total dose: 600 mCi) for lung and left 7th rib metastases. The patient was confirmed RAIrefractory and subsequently developed local recurrence and progressive brain metastasis during follow-up. Systemic therapy with lenvatinib and whole brain radiotherapy were administered.
Results: After one year of treatment, the brain lesions reduced in size, thyroglobulin levels progressively decreased, and the patient remained clinically stable.
Conclusion: RAI-refractory DTC with brain metastasis is rare and associated with a poor prognosis. Systemic therapy combined with localized treatment modalities can effectively control disease progression