The Paradox of Modern Technology in Standardizing Thermal Liver Ablation: Fostering Uniformity or Diversity?

PURPOSE: Currently, significant medical practice variation exists in thermal ablation (TA) of malignant liver tumors with associated differences in outcomes. The IMaging and Advanced Guidance for workflow optimization in Interventional Oncology (IMAGIO) consortium aims to integrate interventional oncology into the standard clinical pathway for cancer treatment in Europe by 2030, by development of a standardized low-complex-high-precision workflow for TA of malignant liver tumors. This study was conducted at the start of the IMAGIO project with the aim to explore the current state and future role of modern technology in TA of malignant liver tumors. MATERIALS AND METHODS: A cross-sectional questionnaire was conducted followed by an expert focus group discussion with core members and collaborating partners of the consortium. RESULTS: Of the 13 participants, 10 respondents filled in the questionnaire. During the focus group discussion, there was consensus on the need for international standardization in TA and several aspects of the procedure, such as planning based on cross-sectional images, the adoption of different techniques for needle placement and the importance of needle position- and post-ablative margin confirmation scans. Yet, also considerable heterogeneity was reported in the adoption of modern technology, particularly in navigational systems and computer-assisted margin assessment. CONCLUSION: This study mirrored the current diversity in workflow of thermal liver ablation. To obtain comparable outcomes worldwide, standardization is needed. While advancements in tools and software hold the potential to homogenize outcome measurement and minimize operator-dependent variability, the rapid increase in availability also contributes to enhanced workflow variation.

Innovations in Image-Guided Procedures: Unraveling Robot-Assisted Non-Hepatic Percutaneous Ablation.

Interventional oncology is routinely tasked with the feat of tumor characterization or destruction, via image-guided biopsy and tumor ablation, which may pose difficulties due to challenging-to-reach structures, target complexity, and proximity to critical structures. Such procedures carry a risk-to-benefit ratio along with measurable radiation exposure. To streamline the complexity and inherent variability of these interventions, various systems, including table-, floor-, gantry-, and patient-mounted (semi-) automatic robotic aiming devices, have been developed to decrease human error and interoperator and intraoperator outcome variability. Their implementation in clinical practice holds promise for enhancing lesion targeting, increasing accuracy and technical success rates, reducing procedure duration and radiation exposure, enhancing standardization of the field, and ultimately improving patient outcomes. This narrative review collates evidence regarding robotic tools and their implementation in interventional oncology, focusing on clinical efficacy and safety for nonhepatic malignancies.

How AI and Robotics Will Advance Interventional Radiology: Narrative Review and Future Perspectives.

The rapid advancement of artificial intelligence (AI) and robotics has led to significant progress in various medical fields including interventional radiology (IR). This review focuses on the research progress and applications of AI and robotics in IR, including deep learning (DL), machine learning (ML), and convolutional neural networks (CNNs) across specialties such as oncology, neurology, and cardiology, aiming to explore potential directions in future interventional treatments. To ensure the breadth and depth of this review, we implemented a systematic literature search strategy, selecting research published within the last five years. We conducted searches in databases such as PubMed and Google Scholar to find relevant literature. Special emphasis was placed on selecting large-scale studies to ensure the comprehensiveness and reliability of the results. This review summarizes the latest research directions and developments, ultimately analyzing their corresponding potential and limitations. It furnishes essential information and insights for researchers, clinicians, and policymakers, potentially propelling advancements and innovations within the domains of AI and IR. Finally, our findings indicate that although AI and robotics technologies are not yet widely applied in clinical settings, they are evolving across multiple aspects and are expected to significantly improve the processes and efficacy of interventional treatments.

Microwave ablation followed by cTACE in 5-cm HCC lesions: does a single-session approach affect liver function?

PURPOSE: Microwave ablation (MWA) and conventional transarterial chemoembolization (cTACE) are locoregional treatments commonly performed in very early, early and intermediate stages of hepatocellular carcinoma (HCC). Despite combined locoregional approaches have shown encouraging results in obtaining complete tumor necrosis, their application in a single session is poorly described. Our aim was to evaluate the safety and efficacy of single-session MWA and cTACE treatment in 5-cm HCCs and its influence on liver function. MATERIALS AND METHODS: All 5-cm HCCs treated by MWA and cTACE performed in a single-session in our Interventional Radiology unit between January 2020 and December 2022 were retrospectively recorded and analyzed. Patients with poor or missing pre- and post-treatment imaging were excluded. Technical success, clinical success, and complications rate were examined as primary endpoints. Pre- and post-treatment liver function laboratory parameters were also evaluated. RESULTS: A total of 15 lesions (mean lesion diameter, 5.0 ± 1.4 cm) in 15 patients (11 men; mean age, 67.1 ± 8.9 years) were retrospectively evaluated. Technical and clinical success were 100% and 73%, respectively. Four (27%) cases of partial response and no cases of progressive or stable disease were recorded. AST and ALT values have found to be significantly higher in post-treatment laboratory tests. No other significant differences between pre- and post-treatment laboratory values were registered. AST and ALT pre- and post-treatment higher differences (ΔAST and ΔALT) were significantly associated with a lower clinical success rate. CONCLUSION: MWA and cTACE single-session approach is safe and effective for 5-cm HCCs, without significant liver function impairment. A post-treatment increase in AST and ALT values may be a predictor for clinical failure.

Advances in Image-Guided Ablation Therapies for Solid Tumors.

Image-guided solid tumor ablation methods have significantly advanced in their capability to target primary and metastatic tumors. These techniques involve noninvasive or percutaneous insertion of applicators to induce thermal, electrochemical, or mechanical stress on malignant tissue to cause tissue destruction and apoptosis of the tumor margins. Ablation offers substantially lower risks compared to traditional methods. Benefits include shorter recovery periods, reduced bleeding, and greater preservation of organ parenchyma compared to surgical intervention. Due to the reduced morbidity and mortality, image-guided tumor ablation offers new opportunities for treatment in cancer patients who are not candidates for resection. Currently, image-guided ablation techniques are utilized for treating primary and metastatic tumors in various organs with both curative and palliative intent, including the liver, pancreas, kidneys, thyroid, parathyroid, prostate, lung, breast, bone, and soft tissue. The invention of new equipment and techniques is expanding the criteria of eligible patients for therapy, as now larger and more high-risk tumors near critical structures can be ablated. This article provides an overview of the different imaging modalities, noninvasive, and percutaneous ablation techniques available and discusses their applications and associated complications across various organs.

Outcomes Analysis of 90Y Radioembolization for Tumors Other Than Metastatic Colorectal Cancer from the RESiN (Radiation-Emitting SIR-spheres in Non-resectable liver tumors) Registry.

PURPOSE: To characterize the response and survival outcomes of yttrium-90 transarterial radioembolization (90Y-TARE) for unresectable, liver-dominant metastases from primary neoplasms other than colorectal carcinoma. MATERIALS AND METHODS: This study included 1474 patients enrolled in the RESiN registry who received resin 90Y-TARE as part of their oncologic management for unresectable primary or secondary liver tumors (NCT02685631). 33% (481/1474) were treated for liver metastases of non-colorectal origin (m-nonCRC), compared to 34% (497/1474) treated for colorectal liver metastases (mCRC) and 34% (496/1474) treated for hepatocellular carcinoma (HCC). Treatment response and cancer survival probabilities were computed and compared for each primary cancer type. The Kaplan-Meier method and log-rank test were used to compare survival outcomes. RESULTS: Radiological responses were observed in 12 unique cancer types, mostly heavily pre-treated malignancies refractory to multiple lines of systemic therapies. The overall use of resin 90Y-TARE in m-nonCRC resulted in better treatment outcomes in terms of duration of response, progression free survival, time to progression and overall survival (P = 0.04, P = 0.02, P = 0.01, P = 0.04). Analyses of cancer cell types revealed that metastatic neuroendocrine tumor, sarcoma, and ovarian, renal, prostate, and breast cancers were associated with superior treatment outcomes, whereas worse treatment outcomes were observed in metastatic lung, gastric, pancreatic and esophageal cancers. CONCLUSION: Real-world data demonstrate the use of resin 90Y-TARE in m-nonCRC refractory to standard chemotherapy. For some cell types, this expanded use achieved superior treatment outcomes relative to the reference standard of mCRC, suggesting the need for inquiry into broadened indications for 90Y-TARE.

Diagnosis and management of radiation cholecystitis as a complication of Y90 radioembolization for hepatocellular carcinoma.

Radiation induced cholecystitis is a known but rare complication of Yttrium90 (Y90) radioembolization of hepatic tumors due to nontarget embolization. Many documented cases of radiation induced cholecystitis have been treated with cholecystectomy, which is significant given the typical patient population undergoing radioembolization tends to be of higher surgical risk. Here, we present a case of a 68 year old male who developed radiation induced cholecystitis status post hepatic radioembolization that resolved with conservative management alone. This case highlights that radiation induced cholecystitis may be successfully and safely treated conservatively.

The Deterioration of Sarcopenia Post-Transarterial Radioembolization with Holmium-166 Serves as a Predictor for Disease Progression at 3 Months in Patients with Advanced Hepatocellular Carcinoma: A Pilot Study.

PURPOSE: The aim of this pilot study is to explore the relationship between changes in sarcopenia before and after one to three months of Transarterial Radioembolization (TARE) treatment with Holmium-166 (166Ho) and its effect on the rate of local response. Our primary objective is to assess whether the worsening of sarcopenia can function as an early indicator of a subgroup of patients at increased risk of disease progression in cases of hepatocellular carcinoma (HCC). METHODS: A single-center retrospective analysis was performed on 25 patients with HCC who underwent 166Ho-TARE. Sarcopenia status was defined according to the measurement of the psoas muscle index (PMI) at baseline, one month, and three months after TARE. Radiological response according to mRECIST criteria was assessed and patients were grouped into responders and non-responders. The loco-regional response rate was evaluated for all patients before and after treatment, and was compared with sarcopenia status to identify any potential correlation. RESULTS: A total of 20 patients were analyzed. According to the sarcopenia status at 1 month and 3 months, two groups were defined as follows: patients in which the deltaPMI was stable or increased (No-Sarcopenia group; n = 12) vs. patients in which the deltaPMI decreased (Sarcopenia group; n = 8). Three months after TARE, a significant difference in sarcopenia status was noted (p = 0.041) between the responders and non-responders, with the non-responder group showing a decrease in the sarcopenia values with a median deltaPMI of -0.57, compared to a median deltaPMI of 0.12 in the responder group. Therefore, deltaPMI measured three months post-TARE can be considered as a predictive biomarker for the local response rate (p = 0.028). Lastly, a minor deltaPMI variation (>-0.293) was found to be indicative of positive treatment outcomes (p = 0.0001). CONCLUSION: The decline in sarcopenia three months post-TARE with Holmium-166 is a reliable predictor of worse loco-regional response rate, as evaluated radiologically, in patients with HCC. Sarcopenia measurement has the potential to be a valuable assessment tool in the management of HCC patients undergoing TARE. However, further prospective and randomized studies involving larger cohorts are necessary to confirm and validate these findings.

The efficacy of coaxial percutaneous iodine-125 seed implantation combined with arterial infusion chemotherapy for advanced pancreatic cancer: a randomized clinical trial.

BACKGROUND: This study aimed to evaluate the clinical efficacy of coaxial percutaneous Iodine-125 (125I) seed implantation in combination with arterial infusion chemotherapy for the treatment of advanced pancreatic cancer (PC) through a randomized controlled trial. METHODS: A total of 101 patients with advanced PC were randomized into two groups: control group treated with systemic intravenous chemotherapy and experimental group that received 125I seed implantation in combination with arterial infusion chemotherapy. Outcomes, including tumor control, abdominal pain relief, and survival time were compared between these two groups (Trial Registration No. KYKT2018-65). RESULTS: Pretreatment abdominal pain scores were comparable between the two groups, whereas the abdominal pain scores at 1- and 3-month post-treatment were significantly lower in the control group than those in the experimental group (1-month: 3.74 ± 1.54 vs. 4.48 ± 1.46, p = .015; 3-month: 3.64 ± 2.21 vs. 5.40 ± 1.56, p < .001). At 3-month post-treatment, computed tomography (CT) scan revealed a significantly higher disease control rate in the experimental group than that in the control group (94.0% vs. 74.5%, p = .007). The median survival time in the experimental group was significantly longer than that in the control group (15-month vs. 9-month, p < .001). CONCLUSION: The combination of coaxial percutaneous 125I seed implantation with arterial infusion chemotherapy could significantly alleviate abdominal pain, improve tumor control rates, and prolong survival time in patients with advanced PC.

Retrospective Long-Term Evaluation of Conventional Transarterial Chemoembolization for Hepatocellular Carcinoma over 20 Years.

The aim of this study was to retrospectively evaluate the effects of conventional transarterial chemoembolization (cTACE) for the treatment of hepatocellular carcinoma over 20 years regarding overall survival (OS) and prognostic factors for OS. During the period from 1996 to 2016, 836 patients with HCC were treated with cTACE. Data evaluation was performed on the basis of pre- and postinterventional MRI and CT scans. Survival analysis was performed by Kaplan-Meier estimator; prognostic factors were determined by the use of Cox regression analysis. Overall, 4084 (mean 4.89 TACE sessions/patient) procedures were assessed. Median OS was 700 days (99% CI, 632.8-767.2). Depending on the indication, patients treated with a neoadjuvant intention showed the best OS (1229 days, 99% CI 983.8-1474.2) followed by curative intention (787 days, 99% CI 696.3-877.7), and then palliative intention (360 days, 99% CI 328.4-391.6). Portal vein thrombosis (HR 2.19, CI 1.63-2.96, and p < 0.01) and Child-Pugh class B or worse (HR 1.44, CI 1.11-1.86, and p < 0.001) were significantly associated with shorter OS. Patients with HCC benefit from TACE after careful patient selection. Portal vein thrombosis and Child-Pugh class B or worse are significantly unfavorable prognostic factors for patients' survival.

Imaging Considerations before and after Liver-Directed Locoregional Treatments for Metastatic Colorectal Cancer.

Colorectal cancer is a leading cause of cancer-related death. Liver metastases will develop in over one-third of patients with colorectal cancer and are a major cause of morbidity and mortality. Even though surgical resection has been considered the mainstay of treatment, only approximately 20% of the patients are surgical candidates. Liver-directed locoregional therapies such as thermal ablation, Yttrium-90 transarterial radioembolization, and stereotactic body radiation therapy are pivotal in managing colorectal liver metastatic disease. Comprehensive pre- and post-intervention imaging, encompassing both anatomic and metabolic assessments, is invaluable for precise treatment planning, staging, treatment response assessment, and the prompt identification of local or distant tumor progression. This review outlines the value of imaging for colorectal liver metastatic disease and offers insights into imaging follow-up after locoregional liver-directed therapy.

Interventional Oncology: 2024 Update.

Interventional Oncology (IO) stands at the forefront of transformative cancer care, leveraging advanced imaging technologies and innovative interventions. This narrative review explores recent developments within IO, highlighting its potential impact facilitated by artificial intelligence (AI), personalized medicine and imaging innovations. The integration of AI in IO holds promise for accelerating tumour detection and characterization, guiding treatment strategies and refining predictive models. Imaging modalities, including functional MRI, PET and cone beam CT are reshaping imaging and precision. Navigation, fusion imaging, augmented reality and robotics have the potential to revolutionize procedural guidance and offer unparalleled accuracy. New developments are observed in embolization and ablative therapies. The pivotal role of genomics in treatment planning, targeted therapies and biomarkers for treatment response prediction underscore the personalization of IO. Quality of life assessment, minimizing side effects and long-term survivorship care emphasize patient-centred outcomes after IO treatment. The evolving landscape of IO training programs, simulation technologies and workforce competence ensures the field's adaptability. Despite barriers to adoption, synergy between interventional radiologists' proficiency and technological advancements hold promise in cancer care.

MR-Guided Transurethral Ultrasound Ablation (TULSA)-An Emerging Minimally Invasive Treatment Option for Localised Prostate Cancer.

The optimal treatment strategy for men with localised prostatic cancer of low and intermediate risk is an actively evolving field. It is important to strike a balance between maximal oncological control and minimal treatment-related complications, which helps preserve the patients' quality of life. MR-guided transurethral ultrasound ablation (TULSA) has emerged as a minimally invasive treatment option for this group of patients. This article aims to provide of a background on TULSA technology, a step-by-step procedural guide of MR-guided TULSA and to summarise the current evidence of TULSA in management of localised prostatic cancer, as well as other potential indications.

Cementoplasty to cryoablation: review and current status.

Recent advances in percutaneous image-guided techniques have empowered interventional radiologists with diverse treatment options for the management of musculoskeletal lesions. Of note, there is growing utility for cementoplasty procedures, with indications ranging from stabilization of bone metastases to treatment of painful vertebral compression fractures. Likewise, cryoablation has emerged as a viable adjunct in the treatment of both primary and secondary bone and soft tissue neoplasms. These treatment options have been progressively incorporated into the multidisciplinary approach to holistic care of patients, alongside conventional radiotherapy, systemic therapy, surgery, and analgesia. This review article serves to outline the indications, technical considerations, latest developments, and evidence for the burgeoning role of cementoplasty and cryoablation in the musculoskeletal system, with an emphasis on pain palliation and tumour control.

Advanced Interventional Treatments in Retinoblastoma Management: A Comprehensive Review.

Retinoblastoma is the most common eye malignancy in children that if left untreated can invade intraocular structures, metastasize, and rarely lead to death. Traditionally treated with systemic chemotherapy, Intra-arterial chemotherapy is gaining popularity as it allows for the direct administration of chemotherapy through the ophthalmic artery, thus reducing systemic side effects. Intra-arterial chemotherapy procedures have evolved, with refinements to reduce risks and radiation exposure. Intra-arterial chemotherapy boasts an impressive technical success rate and one year ocular survival even amongst advanced cases. This review offers a thorough examination of the technique, indications, contraindications, outcomes, and alternative options for Intra-arterial chemotherapy.

Discrepancy Between Achieved and Vendor-Predicted Ablation Zones in the Lung: Contributing Factors.

PURPOSE: Several factors are known to affect lung ablation zones. Questions remain as to why there are discrepancies between achieved and vendor-predicted ablation zones and what contributing factors can be modified to balance therapeutic effects with avoidance of complications. This retrospective study of lung tumour microwave ablation analyses day 1 post-treatment CT to assess the effects of lesion-specific and operator-dependent factors on ablation zones. METHODS AND MATERIALS: Consecutive patients treated at a tertiary centre from 2018 to 2021 were included. All ablations were performed using a single microwave ablation device under lung isolation. The lung tumours were categorised as primary or secondary, and their "resistance" to ablation was graded according to their locations. Intraprocedural pulmonary inflation was assessed as equal to or less than the contralateral non-isolated lung. Ablation energy was categorised as high, medium, or low. Ablation zone dimensions were measured on day 1 CT and compared to vendor reference charts. Ablations with multiple needle positions or indeterminate boundaries were excluded. RESULTS: A total of 47 lesions in 31 patients were analysed. Achieved long axes are longer than predicted by 5 mm or 14% (p < 0.01) without overall short axis discrepancy. Secondary tumours (p = 0.020), low-resistance location (p < 0.01), good lung inflation (p < 0.01), low (p = 0.003) and medium (p = 0.038) total energy produce lengthened long axes by 4-6 mm or 10-19%. High total energy results in shorter than predicated short axes by 6 mm or 18% (p = 0.010). CONCLUSION: We identified several factors affecting ablation zone dimensions which may have implications for ablation planning and the avoidance of complications.

Deep convolutional-neural-network-based metal artifact reduction for CT-guided interventional oncology procedures (MARIO).

BACKGROUND: Computed tomography (CT) is routinely used to guide cryoablation procedures. Notably, CT-guidance provides 3D localization of cryoprobes and can be used to delineate frozen tissue during ablation. However, metal-induced artifacts from ablation probes can make accurate probe placement challenging and degrade the ice ball conspicuity, which in combination could lead to undertreatment of potentially curable lesions. PURPOSE: In this work, we propose an image-based neural network (CNN) model for metal artifact reduction for CT-guided interventional procedures. METHODS: An image domain metal artifact simulation framework was developed and validated for deep-learning-based metal artifact reduction for interventional oncology (MARIO). CT scans were acquired for 19 different cryoablation probe configurations. The probe configurations varied in the number of probes and the relative orientations. A combination of intensity thresholding and masking based on maximum intensity projections (MIPs) was used to segment both the probes only and probes + artifact in each phantom image. Each of the probe and probe + artifact images were then inserted into 19 unique patient exams, in the image domain, to simulate metal artifact appearance for CT-guided interventional oncology procedures. The resulting 361 pairs of simulated image volumes were partitioned into disjoint training and test datasets of 304 and 57 volumes, respectively. From the training partition, 116 600 image patches with a shape of 128 × 128 × 5 pixels were randomly extracted to be used for training data. The input images consisted of a superposition of the patient and probe + artifact images. The target images consisted of a superposition of the patient and probe only images. This dataset was used to optimize a U-Net type model. The trained model was then applied to 50 independent, previously unseen CT images obtained during renal cryoablations. Three board-certified radiologists with experience in CT-guided ablations performed a blinded review of the MARIO images. A total of 100 images (50 original, 50 MARIO processed) were assessed across different aspects of image quality on a 4-point likert-type item. Statistical analyses were performed using Wilcoxon signed-rank test for paired samples. RESULTS: Reader scores were significantly higher for MARIO processed images compared to the original images across all metrics (all p < 0.001). The average scores of the overall image quality, iceball conspicuity, overall metal artifact, needle tip visualization, target region confidence, and worst metal artifact, needle tip visualization, iceball conspicuity, and target region confidence improved by 34.91%, 36.29%, 39.94%, 34.17%, 35.13%, and 45.70%, respectively. CONCLUSIONS: The proposed method of image-based metal artifact simulation can be used to train a MARIO algorithm to effectively reduce probe-related metal artifacts in CT-guided cryoablation procedures.

Exploring software navigation tools for liver tumour angiography: a scoping review.

INTRODUCTION: Liver cancer presents a growing global health concern, necessitating advanced approaches for intervention. This review investigates the use and effectiveness of software navigation in interventional radiology for liver tumour procedures. METHODS: In accordance with Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) guidelines, a scoping review was conducted of the literature published between 2013 and 2023 sourcing articles through MEDLINE, Scopus, CINAHL and Embase. Eligible studies focused on liver cancer, utilised cone-beam computed tomography (CBCT), and employed software for intervention. Twenty-one articles were deemed eligible for data extraction and analysis. RESULTS: Categorised by type, software applications yielded diverse benefits. Feeder detection software significantly enhanced vessel identification, reducing non-target embolisation by up to 43%. Motion correction software demonstrated a 20% enhancement in image quality, effectively mitigating breathing-induced motion artefacts. Liver perfusion software facilitated efficient tumour targeting while simultaneously reducing the occurrence of side effects. Needle guide software enabled precise radiofrequency ablation needle placement. Additionally, these software applications provided detailed anatomical simulations. Overall, software integration resulted in shorter procedures, reduced radiation exposure and decreased contrast media usage. CONCLUSION: This scoping review highlights the innovative yet relatively underexplored role of software navigation for liver tumour procedures. The integration of software applications not only enhances procedural efficiency but also bolsters operator confidence, and contributes to improved patient outcomes. Despite the current lack of uniformity and standardisation, these software-driven advancements hold significant promise for transforming liver tumour interventions. To realise these benefits, further research is needed to explore the clinical impact and optimal utilisation of software navigation tools in interventional radiology.

Quantitative differences in volumetric calculations for radiation dosimetry in segmental Y90 treatment planning using hybrid angiography-CT compared with anatomic segmentation.

OBJECTIVE: To compare treatment volumes reconstructed from hybrid Angio-CT catheter-directed infusion imaging and Couinaud anatomic model as well as the implied differences in Y-90 radiation dosimetry. METHODS: Patients who underwent transarterial radioembolization (TARE) using Y-90 glass microspheres with pretreatment CT or MRI imaging as well as intraprocedural angiography-CT (Angio-CT) were analysed. Treatment volumes were delineated using both tumoural angiosomes (derived from Angio-CT) and Couinaud anatomic landmarks. Segmental and lobar treatment volumes were calculated via semi-automated contouring software. Volume and dose differences were compared by the two-tailed Student t test or Wilcoxon signed-rank test. Factors affecting volume and dose differences were assessed via simple and/or multiple variable linear regression analysis. RESULTS: From September 2018 to March 2021, 44 patients underwent 45 lobar treatments and 38 patients received 56 segmental treatments. All target liver lobes and all tumours were completely included within the field-of-view by Angio-CT. Tumour sizes ranged between 1.1 and 19.5 cm in diameter. Segmental volumes and treatment doses were significantly different between the Couinaud and Angio-CT volumetry methods (316 vs 404 mL, P < .0001 and 253 vs 212 Gy, P < .01, respectively). Watershed tumours were significantly correlated with underestimated volumes by the Couinaud anatomic model (P < .001). There was a significant linear relationship between tumour diameter and percent volume difference (R2 = 0.44, P < .0001). The Couinaud model overestimated volumes for large tumours that exhibited central hypovascularity/necrosis and for superselected peripheral tumours. CONCLUSIONS: Angio-CT may confer advantages over the Couinaud anatomic model and enable more accurate, personalized dosimetry for TARE. ADVANCES IN KNOWLEDGE: Angio-CT may confer advantages over traditional cross-sectional and cone-beam CT imaging for selective internal radiation therapy planning.

CT-guided high dose rate brachytherapy can induce multiple systemic proteins of proliferation and angiogenesis predicting outcome in HCC.

BACKGROUND AND PURPOSE: To determine the potential prognostic value of proliferation and angiogenesis plasma proteins following CT-guided high dose rate brachytherapy (HDR-BT) of hepatocellular carcinoma (HCC). MATERIALS AND METHODS: For this prospective study, HDR-BT (1 × 15 Gy) was administered to 24 HCC patients. Plasma was obtained and analyzed using an Olink proteomics Target-96 immuno-oncology-panel that included multiple markers of angiogenesis and proliferation. Fold-change (FC) ratios were calculated by comparing baseline and 48 h post HDR-BT paired samples. Patients were classified as responders (n = 12) if they had no local progression within 6 months or systemic progression within 2 years. Non-responders (n = 12) had recurrence within 6 months and/or tumor progression or extrahepatic disease within 2 years. RESULTS: Proliferation marker EGF was significantly elevated in non-responders compared to responders (p = 0.0410) while FGF-2, HGF, and PlGF showed no significant differences. Angiogenesis markers Angiopoietin-1 and PDGF-B were likewise significantly elevated in non-responders compared to responders (p = 0.0171, p = 0.0462, respectively) while Angiopoietin-2, VEGF-A, and VEGFR-2 did not differ significantly. Kaplan-Meier analyses demonstrated significantly shorter time to systemic progression in patients with increased EGF and Angiopoietin-1 (p = 0.0185, both), but not in patients with one of the remaining proteins elevated (all p > 0.1). Pooled analysis for these 9 proteins showed significantly shorter time to systemic progression for FC ≥1.3 and ≥1.5 for at least 3 proteins elevated (p = 0.0415, p = 0.0193, respectively). CONCLUSION: Increased plasma levels of EGF and Angiopoietin-1 after HDR-BT for HCC are associated with poor response and may therefore function as predictive biomarkers of outcome.