Objective To evaluate the adequacy of Rapid Onsite Evaluation (ROSE) in relation to diagnostic yield of CT-guided percutaneous lung core needle biopsies (CNB) at a tertiary care cancer center. Methods A total of 943 CT-guided percutaneous CNB performed in the year 2022 were retrospectively reviewed. ROSE of specimens provided immediate feedback regarding the sample adequacy. The biopsies were divided into 3 groups based on ROSE results: 1) adequate on first pass; 2) adequate after repeat sampling and 3) inadequate. Patient, lesion, and procedure characteristics were analyzed in relation to ROSE adequacy using a multinomial logistic regression model. Results Median lesion size was 1.8 cm (IQR: 1.2-2.8). The first-pass adequacy rate was 64.8% (611/943), increasing to 82.4% (777/943) after seven passes, with a clear plateau after three passes; 17.9% (169/943) samplings were persistently inadequate. Complete histopathologic processing resulted in an overall diagnostic yield of 89.7% (846/943). Critically, 59.2% of biopsies deemed inadequate by ROSE ultimately yielded a diagnostic result after complete pathologic processing. ROSE demonstrated a sensitivity of 88.2%, specificity of 71.1%, positive predictive value of 96.4%, and negative predictive value of 40.8%. Larger lesion size and absence of perilesional hemorrhage were associated with higher odds of first-pass adequacy on multivariable analysis. Conclusion Lesion size and perilesional hemorrhage are independent predictors of ROSE- adequacy for lung CNB. The low negative predictive value (40.8%) and the finding that 59.2% of ROSE-inadequate biopsies ultimately yielded a diagnostic result highlight that ROSE inadequacy should not be interpreted as synonymous with biopsy failure.

RATIONALE AND OBJECTIVES:To quantify changes in procedure times for interventional radiology (IR) attendings post-fellowship. MATERIALS AND METHODS:Between 8/2010 and 12/2023, we examined 67943 procedures across 269 procedures for 24 IR attendings post-fellowship at a tertiary teaching hospital. Procedure time and months of attending practice were collected to create procedure time learning curves for individual procedures. Procedure times at 1 year and 6-12 years of practice were compared using student's t-test. To create an aggregate learning curve across all procedures, a normalized procedure time (NPT) was calculated by subtracting a faculty's median career procedure time from their individual procedure times across periods of attending practice. RESULTS:Sirsphere treatment showed the greatest reduction in procedure time between 1 and 6-12 years of practice (232 vs 155 mins, p<0.001), followed by soft tissue ablation (173 vs 120 mins, p<0.001), mapping arteriogram (216 vs 164 mins, p<0.001), embolization tumor hepatic (229 vs 185 mins, p<0.001), bone marrow aspiration (75 vs 50 mins, p<0.001), nephrostomy exchange (71 vs 53 mins, p<0.001) and pleurx catheter placement (87 vs 71 mins, p<0.001). The aggregate IR procedure time learning curve showed decreasing NPT in year 1 (-5.3 mins/procedure/year, p< 0.19), followed by slower steady significantly decreasing NPT between 1 and 6-12 years of practice (-0.7 mins/procedure/year, p<0.0001). CONCLUSION:During the first year of practice post-fellowship, IR attendings have the greatest reduction in procedure times for locoregional cancer treatments. Aggregating all procedures during the first 12 years post-fellowship, IR attendings demonstrate a biphasic learning curve.

BACKGROUND Micropapillary and solid subtypes of lung adenocarcinoma are associated with high rates of recurrence in early-stage non-small cell lung cancer and may help guide the extent of resection if known preoperatively. We examined the accuracy of CT-guided core needle biopsy in determining high-risk subtypes in small (≤2 cm) tumors. METHODS A retrospective review was performed to identify patients with clinical T1a-T1bN0M0 (≤2 cm) lung adenocarcinoma who underwent CT-guided core needle biopsy before surgical resection from 2010 to 2024. The accuracy, sensitivity, and specificity of preoperative biopsy were determined for each histologic subtype. Multivariable logistic regression identified preoperatively known clinicopathologic risk factors for micropapillary/solid subtypes on surgical pathology. RESULTS We identified 658 patients with early-stage lung adenocarcinoma who underwent preoperative biopsy, with 372 (57%) patients undergoing core-needle biopsy resulting in a pathology specimen with histologic subtype reported. Preoperative biopsy was highly specific (96.9%) but not sensitive (37.1%) for the presence of solid or micropapillary subtypes. Of the 288 patients without a high-risk subtype identified on preoperative biopsy, 134 (47%) had a high-risk subtype identified on surgical pathology. Multivariable analysis identified male sex, current/former smoking history, tumor maximum standardized uptake value (SUVmax), and solid tumor CT texture as independently associated with greater risk of having micropaillary/solid features on surgical pathology. CONCLUSIONS Preoperative biopsy is effective at ruling in, but not ruling out, high-risk lung adenocarcinoma subtypes. The presence of high-risk features on biopsy may be helpful in treatment planning.

Purpose To develop a lung-specific deformable image registration algorithm optimized for lung thermal ablation and evaluate whether three-dimensional (3D) margin assessment predicts time to local recurrence. Materials and Methods This institutional review board-approved, single-institution retrospective study evaluated patients who underwent lung thermal ablation with available pre- and postprocedural CT scans suitable for deformable registration. Images were preprocessed with segmentation of tumor, ablation zone, and lung. A four-stage deformable image registration framework was applied: (a) affine registration, (b) deformable image registration to the cropped lung, (c) lung mask-guided deformable image registration, and (d) local deformable image registration focused on the neighborhood adjacent to the ablation zone. Registrations were performed using free-form B-spline transformations with cost function masking of the ablation zone. Registration accuracy was assessed using target registration error (TRE). The 3D ablation margins were quantified using a distance-transform-based analysis of the spatial relationship between the tumor surface and ablation zone boundary. Associations between margin size and time to local recurrence were evaluated using competing-risks regression, and time-dependent receiver operating characteristic analysis was performed. Results A total of 69 patients (median age, 59 years [IQR, 50-69 years]; 38 female) with 108 ablated lung tumors were included. Mean TRE ± SD was 0.4 mm ± 0.3 and mean ablation margin was 1.6 mm ± 2.1. Larger margins were associated with longer time to local recurrence (subdistribution hazard ratio, 0.5 per millimeter increase [95% CI: 0.4, 0.6]; P < .001) and remained independently associated on multivariate analysis. Using a 2-mm margin threshold, the 2-year local recurrence rate was 3% (95% CI: 1, 8). The area under the receiver operating characteristic curve for predicting 2-year local recurrence was 0.86. Conclusion The four-step lung-optimized deformable image registration framework enabled accurate automated 3D tumor ablation margin quantification, and margin size was associated with time to local recurrence. Keywords: Ablation Techniques, Interventional-Oncology, Percutaneous, Thorax, Lung, Computer Applications-3D, Computational Studies, CT © RSNA, 2026.

Denoising diffusion models (DDMs) have demonstrated strong generative capabilities for realistic image generation, and their ability to encode uncertainty has motivated applications for medical imaging such as tumor segmentation. Training and inference of denoising diffusion probabilistic models (DDPMs) on whole 3D medical scans is memory-intensive and computationally slow. Prior studies have addressed this challenge using accelerated sampling strategies such as denoising diffusion implicit models ( DDIM) and latent space compression approaches such as latent diffusion models, demonstrating improvements in computational efficiency. However, these methods still exhibit high inference times for full 3D volumes, posing a significant challenge for time-sensitive clinical workflows where rapid turnaround is essential. We have developed a novel human-assisted DDM approach (HA-DDM) to address this problem that integrates human guidance for interactive and fast medical image segmentation. Our method takes a user-defined point approximately at the center of the structure to be segmented as an input prompt and crops the image scan to a 3D bounding box region of interest (ROI) of a pre-determined size around the structure, centered at the point. This is fed to the DDPM and DDIM to obtain the output 3D segmentation, which is pre-trained using bounding box ROIs of similar size around the tumor extracted from the training data. We sample multiple segmentations using the DDPM and DDIM to generate spatial uncertainty maps. These segmentations are then ensembled to create the results which are resampled into the full 3D scan space. Our approach improves memory and computational efficiency of DDMs by processing smaller 3D bounding boxes instead of full 3D scans. In this work, we demonstrated our approach for lung tumor segmentation on 2D slices and 3D ROI bounding boxes. We validated our method on held-out test sets, achieving median Dice scores of 0.73 and 0.92 on the Medical Decathlon and institutional 2D datasets respectively using DDPM. For 3D volumes, we achieved Dice scores of 0.77 using DDIM on the institutional dataset with just 20 denoising steps instead of the standard 1000 in DDPM, significantly reducing computational time and resources without sacrificing segmentation quality.

We quantified volume and shape variability in lung microwave ablation (LMWA) zones, comparing them with expected ablation zones, exploring the correlation with tissue contraction. After Institutional Review Board approval, we retrospectively included patients who underwent LMWA between January 2015 and January 2019. Exclusion criteria were ablations with multiple burns/probes, overlapping ablation zones, or indistinguishable background lung parenchyma. Ablation zones were oriented along an applicator-centric coordinate system. We used Pyradiomics to generate volumes and the Euler characteristic transform for three-dimensional shape space analysis. Wilcoxon paired signed-rank tests compared the expected versus the actual ablation zone. Tissue contraction was quantified using paired anatomical landmarks before and after computed tomography scans. We included 111 ablations in 72 patients (31 male, 41 female; median age 59). Median ablation power was 65 watts (range 20‒65), median ablation time 5 min (range 1‒10). Total energy correlated with volume and width (p = 0.007, p = 0.003, respectively). Ablation volume did not differ from vendor predictions (p = 0.452), whereas length (p < 0.001) and maximum width (p < 0.001) were greater than predicted. Ablation shapes were more elongated (p < 0.001), less spherical (p < 0.001), asymmetric (wider in back than in front, p = 0.007), and diverged from expected ellipsoids. There was no correlation between tissue contraction and volume, power, or time. The provided vendor model offers a reasonable estimate of mean ablation volume, but wide variability in volume and shape necessitates a more bespoke method of ablation zone prediction. Tissue contraction did not correlate with ablation zone variability. High variability in actual ablation volume, shape, length, width, and position along the needle and divergence from ellipsoids necessitates the development of improved ablation zone prediction models.

Objective:To compare the safety and efficacy of transarterial embolization (TAE) and transarterial radioembolization (TARE) in the treatment of lung carcinoid liver metastasis. Method:This retrospective, single-institution study included 30 patients with lung carcinoid liver metastasis treated with 53 primary embolization procedures (24 TARE; 29 TAE) between 2009 and 2022. Survival analyses were performed using the Kaplan-Meier method. Adverse events were assessed using the Common Terminology Criteria of Adverse Events Version 5.0. Results:The local tumor progression-free survival (LTPFS) for the entire cohort was 16.2 (95% confidence interval [CI]: 12.6-22.2) months. Factors associated with poor LTFPS for all patients included chromogranin A positivity (hazard ratio [HR]: 10.13, 95% CI: 2.32-44.31, p = 0.002), previous octreotide treatment (HR: 2.37, 95% CI: 1.12-5.01, p = 0.01), and previous everolimus treatment (HR: 2.4, 95% CI: 1.12-5.01, p = 0.02).TARE was associated with significantly improved LTPFS; 30.57 (95% CI: 12.4-33.4) months compared with TAE 13.9 (95% CI: 10.87-20.13) months, (p = 0.01). Patients on concurrent everolimus at the time of TARE had a significant improvement in LTPFS (HR: 0.25, 95% CI: 0.16-0.41, p < 0.001).The median overall survival of the entire cohort was 43.5 (95% CI: 20.5-55.9) months; 40.6 (95% CI: 20-49.0) months for TAE versus 43.5 (95% CI: 12.3-61.4) months for TARE (p = 0.49).Postprocedure adverse events occurred in 28 out of 74 (38%) treatments, most being grade 1 and 2 (n = 24). Severe adverse events (Common Terminology Criteria of Adverse Events grade ≥3) included severe vomiting after TARE (2), acute kidney injury after TAE (1), and bacteremia after TAE (1). Conclusion:TARE exhibited better local tumor control compared with TAE in patients with lung carcinoid, with no significant difference in overall survival. Both hepatic arterially directed therapies exhibited acceptable safety profiles.

Interventional radiologists are key members of the multidisciplinary team involved in the care of patients with primary or metastatic neoplastic disease in the thorax. Percutaneous ablation is a safe and efficacious treatment of lung tumors, especially for patients with medical comorbidities or oligometastatic disease. Endovascular approaches can benefit patients with thoracic oncologic disease by allowing for primary arterial treatment, preoperative embolization, or embolization for tumor-related hemoptysis. Drainage and shunt procedures can help alleviate symptoms in patients with malignant pleural effusions, chylothoraces, and pericardial effusions. The authors summarize several available minimally invasive interventions to the thorax for tumor treatment and symptom palliation. ©RSNA, 2025.

The aim of this study was to evaluate associations between TP53 status and outcomes after transarterial embolization (TAE) for the treatment of patients with hepatocellular carcinoma (HCC). This single-institution study included patients from 1/2014 to 6/2022 who underwent TAE of HCC and genomic analysis of tumoral tissue. The primary outcome was overall survival (OS) with relation to TP53 status, and the secondary outcome was the time to progression. Survival analysis was performed using the Kaplan–Meier method. The time to progression with death or the last patient contact without progression as competing risks were used to obtain a cumulative incidence function, and the association with TP53 status was evaluated using the Gray test. In total, 75 patients (63 men) with a median age of 70.0 (IQR 62.0–76.3) years were included. Of these, 26/75 (34.7%) patients had TP53-mutant HCC. Patients with TP53-mutant HCC had a significantly worse median OS of 15.2 (95% CI, 9.5–29.3) months, versus 31.2 (95% CI, 21.2–52.4) months as the median OS (p = 0.023) for TP53 wild-type HCC. Competing risk analysis showed a shorter time to local hepatic progression (at the site of the previously treated tumor) after TAE in patients with TP53-mutant HCC. The cumulative incidences of local progression at 6 and 12 months for TP53-mutant HCC were 65.4% and 84.6%, versus 40.8% and 55.1% for TP53 wild-type HCC (p = 0.0072). A TP53 mutation may predict a worse overall survival and a shorter time to local progression in HCC patients treated with TAE.

PURPOSE:To evaluate the safety and feasibility of treating pancreatic tumors in an Oncopig tumor model, using bumetanide (BU)/ethiodized oil emulsion. MATERIALS AND METHODS:Pancreatic tumors were induced in 18 transgenic Oncopigs with inducible p53 and Kras mutations. Sixteen pigs developed tumor and were treated with intra-arterial (IA) injection of BU/ethiodized oil emulsion (n = 6) (mean injected volume, 1.8 mL of 2.9 mL of ethiodized oil + 2.10 mL [0.44 mg, 0.02 mg/kg] of BU), IA injection of ethiodized oil (n = 3), and systemic intravenous gemcitabine (n = 2). Five pigs did not receive any treatment (control). Laboratory evaluation and contrast-enhanced computed tomography (CT) scan was obtained on Days 0, 7, and 14. Necropsy was performed on Day 14. Treatment was evaluated by tumor size change, radiographic response per Response Evaluation Criteria in Solid Tumors 1.1 at Day 14, and degree of tumor necrosis on histopathological examination. One-way analysis of variance and the Tukey-Kramer post hoc test were used. RESULTS:Median tumor diameter before treatment was 1.5 cm (interquartile range [IQR], 1.1-3.1 cm). No significant increase in the posttreatment serum lipase levels was detected in the BU/ethiodized oil group (P > .05). No clinical, radiographic, or histopathological evidence of pancreatitis was detected. Tumor size in the BU/ethiodized oil group decreased by a median of 10.3% (6.7%-13.6%, P < .05). The control group had an increase in median (IQR) tumor size by 45% (32.8%-61.4%, P < .05). The median tumor size change was significantly different between the BU/ethiodized oil and control groups (P = .01). Mean degree of necrosis was less than 10% in the treated groups (P > .05). CONCLUSIONS:IA injection of BU/ethiodized oil emulsion is safe and feasible in treating pancreatic tumor in a transgenic porcine model.

The current guidelines for the treatment of extrathoracic metastases secondary to thymic neoplasms recommend chemotherapy. Thymic carcinomas are radiosensitive, and radiation therapy is recommended for intrathoracic masses and isolated metastases that are not amenable to resection. Liver-directed therapy, particularly yttrium-90 radioembolization, has been used for the treatment of oligometastatic diseases in the liver from various primaries. Here, we report three cases of radioembolization for the treatment of thymic carcinoma that metastasized to the liver.

PURPOSE:To evaluate the safety and efficacy of transarterial therapy, including hepatic arterial embolization (HAE) and transarterial radioembolization (TARE), for patients with hepatic metastases secondary to pancreatic acinar cell carcinoma (PACC). METHODS:This retrospective, single-center study included patients with PACC liver metastases treated with transarterial therapy between 11/2013 and 2/2023. Nine patients with PACC were treated in a total of 18 sessions [HAE (n = 14), and TARE (n = 4)]. Patient demographics, tumor characteristics, and radiographic response were recorded. Local tumor progression-free survival (LTPFS) and overall survival (OS) were assessed via Kaplan-Meier analysis. Adverse events were graded according to Common Terminology Criteria for Adverse Events (CTCAE) v5. RESULTS:Median LTPFS was 6.77 months (95 % CI: 3.23-26.33 months) after first treatment. Median assisted LTPFS in the six patients with multiple treatment sessions was 22.33 months (95 % CI: 3.67-31.93 months). Median OS was not reached (95 % CI: 0.17-NR). One-year OS from first treatment was 66.67 % (95 % CI: 28.17-87.83 %). Adverse events within one month of treatment occurred in 5/18 (27.8 %) sessions. Three of the five (60 %) reported complications were grade 1 and included mild post-embolization syndrome. One grade 3 complication occurred; pulmonary embolism associated with hypoxia and treated with anticoagulation. There was one death, grade 5, five days after treatment in a patient with a history of pancreaticoduodenectomy who developed a hepatic abscess complicated by sepsis. CONCLUSION:This small retrospective study suggests that transarterial therapies for PACC provide acceptable local control and safety.

Purpose: This study examines the association between tumor volume doubling time (TVDT) and clinical outcomes for patients with hepatocellular carcinoma (HCC) treated with transarterial embolization (TAE) and evaluates the impact of tumor genotype on TVDT. Methods: This was a retrospective cohort study at a single tertiary care cancer center, including treatment-naïve patients with biopsy-proven HCC treated with TAE from 1/2014 to 6/2022. The patients underwent initial baseline contrast-enhanced cross-sectional imaging more than 30 days prior to embolization. Index tumors were defined as the largest HCC present on baseline imaging treated with TAE, and TVDT was calculated using Schwartz’s equation with perpendicular trans-axial measurements. Genetic mutation analysis was performed on HCC tissue specimens using next-generation sequencing. Survival analysis was performed using the Kaplan–Meier method, and Cox regression was used to assess prognostic factors for survival. Results: Patients with a TVDT ≤ 2.5 months had a worse overall survival (OS) after TAE (p = 0.011). On multivariate regression analysis, predictors of worse OS following TAE included TVDT ≤ 2.5 months (p = 0.036), Eastern Cooperative Oncology Group (ECOG) performance score of 1 or 2 (p = 0.006), and alpha fetoprotein > 200 ng/mL (p = 0.013). The presence of ≥5 HCC tumors on initial imaging was associated with a worse local tumor progression-free survival (LTPFS) on multivariate analysis (p = 0.002). No single genetic mutation was associated with shorter TVDT. Conclusion: Patients with HCC exhibiting rapid growth, defined as shorter TVDT, may be associated with worse overall survival following TAE. Rapid tumor growth does not seem to be correlated with a single genetic mutation.

Small cell lung cancer (SCLC) is a high-grade neuroendocrine carcinoma associated with early development of distant metastases, which portends a worse prognosis. The median survival of metastatic SCLC with standard treatment is only 9-11 months, with a 5-year survival of 1-2%. Patients with SCLC are often initially responsive to systemic therapies, but once they develop resistance to them, locoregional therapies like thermal ablation should be investigated for possible improvements in morbidity and mortality. This brief retrospective report evaluates six patients with SCLC liver metastases (LMs), treated in 11 thermal ablation sessions (radiofrequency ablation or microwave ablation). Technical success was achieved in all treatments (100%). After the first ablation, 3/7 ablated tumors had residual disease. Survival outcomes were determined using the Kaplan-Meier method. Median local tumor progression-free survival (LTPFS) was 2.9 [95% confidence interval (CI): 0.5-3.9] months. Median assisted LTPFS, defined as tumor control with subsequent retreatment, was 25.9 (95% CI: 8.3-not reported) months. Median overall survival (OS) was 14.3 months. There was one adverse event (1/11) of grade 1, according to the Common Terminology Criteria for Adverse Events version 5.0, fatigue within a month of ablation, which self-resolved. The results suggest that thermal ablation is safe for SCLC LMs. Although LTPFS was very modest, the long duration of assisted LTPFS and OS in this small, retrospective study suggests that thermal ablation may be a promising treatment option.

Haemoptysis in patients with lymphoma and leukaemia can present a therapeutic challenge, given that it is often associated with underlying impairments of haemostasis and immunosuppression. Bronchial artery embolization (BAE) is a mainstay in the treatment of haemoptysis, typically in those requiring emergent management. In this case series, the role of BAE in patients with lymphoma and leukaemia was evaluated. A total of 5 patients were identified between August 2010 and August 2022. Three patients were diagnosed with lymphoma (classical Hodgkin's lymphoma, diffuse large B-cell lymphoma and extra-nodal marginal zone lymphoma) and 2 patients were diagnosed with leukaemia (1 patient with acute myeloid leukaemia and the other with chronic lymphocytic leukaemia). All patients were thrombocytopenic [77.6 ± 28.5 × 109/L (mean ± SD)], at presentation. Three patients had concurrent lung infection at the time of their presentation. Technical success was achieved in 4/5 patients (80%). Clinical success was obtained in 4/5 patients (80%). Recurrence following embolization was seen in 2 patients. Three patients died within 30 days following embolization (from deteriorating respiratory function). Bronchial artery embolization for haemoptysis in patients with lymphoma and leukaemia is safe and feasible. Concurrent lung infection is potentially of significance with regard to initial presentation and overall outcomes following embolization. In select patients, BAE may provide a therapeutic option, though further investigation is required.

INTRODUCTION:Metastatic liver pancreatic neuroendocrine tumors (PNETs) can be treated with ischemia-based trans-arterial embolization/trans-arterial chemo-embolization or radiation-based trans-arterial radioembolization (TARE). Guidelines for treatment selection are limited. The purpose of this study was to measure the effect of loss of DAXX/ATRX protein expression on ischemia and radiation sensitivity in Bon-1 and QGP-1 cells, and to compare TARE response in PNETs with and without a DAXX/ATRX mutation. METHODS:This was a laboratory investigation and retrospective review of an institutional database of TARE-treated PNET patients. Ischemia and radiation sensitivity were tested on Bon-1 and QGP-1 cells and CRISPR-generated DAXX (C16/C45) and ATRX (QAX12/QAX24) knockouts. Post-ischemia and postradiation cell viability, survival fraction, and caspase-3 expression were measured. Local progression-free survival (LPFS) was measured from time of TARE to local progression or death and estimated using Cox proportional hazards. RESULTS:Post-ischemia DAXX (C16/C45) and ATRX (QAX12/QAX24) knockouts had increased cell viability compared with Bon-1 wild-type cells (p < 0.0001, days 3, 5) and QGP-1 wild-type cells (p < 0.0001, days 3, 5, 7). Postradiation C16/C45 and QAX12/QAX24 had decreased survival fraction compared with respective wild type (p < 0.0001, all cell lines). C16/C45 had decreased apoptotic activity post-ischemia and increased apoptotic activity postradiation compared with wild type (p < 0.0001, all cell lines). Presence of DAXX/ATRX mutation was associated with longer LPFS after TARE (p < 0.001). Median LPFS after TARE was 6 months in wild type compared with 22 months in patients with DAXX/ATRX mutation. CONCLUSION:Loss of DAXX/ATRX protein expression is associated with ischemia resistance and radiation sensitivity in Bon-1 and QGP-1 cells and longer LPFS after TARE in PNET patients.

PURPOSE:To determine safety and efficacy of Yttrium-90 transarterial radioembolization (TARE) for neuroendocrine liver metastases (NLM). MATERIALS AND METHODS:Retrospective analysis of 39 patients [17 male; mean age 65.5 years (SD ± 12.25)] who underwent 57 TARE treatments with glass/resin microspheres from 4/2012-12/2022. Primary site included: pancreas (n = 16), small bowel (n = 7), rectum (n = 4), lung (n = 5), NET of unknown origin (n = 4), colon (n = 1), kidney (n = 1), and stomach (n = 1). Overall survival (OS) and time to ascites development were estimated via Kaplan-Meier method. Cox proportional hazards models assessed association between patient characteristics and OS. Local tumor progression (LTP) was analyzed using a competing risks framework with death without local progression treated as the competing risk. Complications were graded via: Common Terminology Criteria for Adverse Events. RESULTS:Cumulative incidence of LTP was 45 % (95 % CI: 31 %-59 %) at 1-year among all procedures. Ki-67 index was significantly associated with local progression; tumors with a Ki-67 index of more than 20 % had increased risk of recurrence vs those with Ki-67 ≤20 % (HR = 2.82, 95 % CI (1.24, 6.39); p = 0.013). Median OS was 31 months (95 %CI: 20-NR). Patients with tumor burden ≥50 % vs <50 % of liver volume had an increased risk of death, though this was not statistically significant (HR = 2.24, 95 %CI (0.92, 5.44); p = 0.075). Two patients (3.5 %, 95 % CI: 0.4 %, 12.1 %) developed complications within 30 days requiring hospitalization: fatigue, nausea, and pain (grade 1); spinal infarct with motor and sensory losses (grade 3). CONCLUSION:TARE is safe for NLM. LTP was better in patients with lower Ki-67 index.

To evaluate oncologic outcomes after microwave ablation (MWA) of colorectal pulmonary metastases, with focus on disease control without chemotherapy. This institutional review board-approved retrospective study examined patients with oligometastatic or oligoprogressive colorectal pulmonary metastases undergoing MWA between January 2011 and December 2021. Imaging response was assessed with CT at 4–8 weeks post-MWA, with subsequent cross-sectional follow-up imaging every 2–4 months. Local tumor progression-free survival (LTPFS), chemotherapy-free survival (CFS) and overall survival (OS) were calculated using Kaplan–Meier methodology. Variables were evaluated for predictive significance using the log-rank test and Cox regression. Two hundred twenty-five patients (127 male, 98 female; median age: 55 years) with 720 pulmonary metastases underwent 400 MWA sessions (mean number of treated metastases per session: 1.8; range 1–9). Mean treated tumor size was 0.9 cm. LTPFS at 1, 2 and 3-years was 91.9