Evaluation of preventive tract embolization with standardized gelatin sponge slurry on chest tube placement rate after CT-guided lung biopsy: a propensity score analysis.

BACKGROUND: To evaluate the effect of tract embolization (TE) with gelatin sponge slurries during a percutaneous lung biopsy on chest tube placement and to evaluate the predictive factors of chest tube placement. METHODS: Percutaneous CT-guided lung biopsies performed with (TE) or without (non-TE) tract embolization or between June 2012 and December 2021 at three referral tertiary centers were retrospectively analyzed. The exclusion criteria were mediastinal biopsies, pleural tumors, and tumors adjacent to the pleura without pleural crossing. Variables related to patients, tumors, and procedures were collected. Univariable and multivariable analyses were performed to determine risk factors for chest tube placement. Furthermore, the propensity score matching analysis was adopted to yield a matched cohort. RESULTS: A total of 1157 procedures in 1157 patients were analyzed, among which 560 (48.4%) were with TE (mean age 66.5 ± 9.2, 584 men). The rates of pneumothorax (44.9% vs. 26.1%, respectively; p < 0.001) and chest tube placement (4.8% vs. 2.3%, respectively; p < 0.001) were significantly higher in the non-TE group than in the TE group. No non-targeted embolization or systemic air embolism occurred. In the whole population, two protective factors for chest tube placement were found in univariate analysis: TE (OR 0.465 [0.239-0.904], p < 0.05) and prone position (OR 0.212 [0.094-0.482], p < 0.001). These data were confirmed in multivariate analysis (p < 0.001 and p < 0.0001 respectively). In the propensity matched cohort, TE reduces significatively the risk of chest tube insertion (OR = 0.44 [0.21-0.87], p < 0.05). CONCLUSIONS: The TE technique using standardized gelatin sponge slurry reduces the need for chest tube placement after percutaneous CT-guided lung biopsy. CRITICAL RELEVANCE STATEMENT: The tract embolization technique using standardized gelatin sponge slurry reduces the need for chest tube placement after percutaneous CT-guided lung biopsy. KEY POINTS: 1. Use of tract embolization with gelatine sponge slurry during percutaneous lung biopsy is safe. 2. Use of tract embolization significantly reduces the risk of chest tube insertion. 3. This is the first multicenter study to show the protective effect of tract embolization on chest tube insertion.

Transarterial chemoembolization (TACE) for neuroendocrine liver metastasis (NELM): Predictive value of volumetric arterial enhancement (VAE) on baseline MRI.

BACKGROUND: Neuroendocrine tumors (NETs) belong to a rare family of tumors whose incidence has increased significantly over the past 50 years. PURPOSE: To evaluate the prognostic value of volumetric arterial enhancement (VAE) on baseline magnetic resonance imaging (MRI) for patients with neuroendocrine liver metastasis (NELM) treated using transarterial chemoembolization (TACE). MATERIAL AND METHODS: Between October 2012 and December 2018, VAE in 37 patients was measured with a semi-automatic volume of Interest (VOI) on subtracted T1 sequence in the arterial phase. Patients underwent 1-3 sectoral lipiodol TACE. Radiologic response using modified Response Evaluation Criteria in Solid Tumors (mRECIST) at the treatment cycle end and progression free survival were determined. RESULTS: Median age was 68.0 (60.0; 73.0). Twenty-three patients (62%) had a partial response, 10 (27%) had stable disease, four (11%) had progressive disease. VAE was a significant (P<0.05) predictor of radiologic response. Median progression free survival was 13 months (IC 95: 8; 16). In univariate analysis, significant predictors of local progression were alkaline phosphatase (AP) (P=0.035), Ki-67 index (P=0.014), and VAE (P<0.01). VAE over 500ms and Ki-67 index over 3%were risk factors of progression (P=<0.01) in multivariate analysis. CONCLUSION: VAE before TACE could be predictive of radiologic response and could be related to oncologic outcomes in patients with NELM.

Preoperative liver arterial conditioning in patients scheduled for a Mayo Clinic class Ia distal pancreatectomy: embolization or ligation?

BACKGROUND: Liver ischemia may occur during intraoperative common hepatic artery ligation in Mayo Clinic class I distal pancreatectomy with en bloc celiac axis resection (DP-CAR). Preoperative liver arterial conditioning could be used to avoid this outcome. This retrospective study compared arterial embolization (AE) or laparoscopic ligation (LL) of the common hepatic artery before class Ia DP-CAR. METHODS: From 2014 to 2022, 18 patients were scheduled for class Ia DP-CAR after neoadjuvant FOLFIRINOX treatment. Two were excluded due to hepatic artery variation, six underwent AE, ten underwent LL. RESULTS: Two procedural complications occurred in the AE group: an incomplete dissection of the proper hepatic artery and a distal migration of coils in the right branch of the hepatic artery. Neither complication prevented surgery. The median delay between conditioning and DP-CAR was 19 days; decreased to five days in the last six patients. None required arterial reconstruction. Morbidity and 90-day mortality rates were 26.7% and 12.5%, respectively. No patient developed postoperative liver insufficiency after LL. CONCLUSION: Preoperative AE and LL seem comparable in averting arterial reconstruction and postoperative liver insufficiency in patients scheduled for class Ia DP-CAR. However, serious complications that may arise during AE led us to prefer the LL technique.

An ultra-low-dose protocol for computed tomography-guided lung radiofrequency ablations.

To evaluate the safety and efficacy of ultra-low-dose (ULD) protocol for computed tomography (CT)-guided lung radiofrequency ablation (RFA). Patients who had undergone lung RFA between November 2017 and January 2021 were consecutively and retrospectively included. Thirty patients were treated using a conventional standard protocol (SP), including helical acquisitions with mA automatic adjustment and sequential CT at 80 kVp; and 31, with a ULD protocol defined with helical acquisitions with fixed mA and sequential series at 100 kVp. These parameters were selected from those used for a diagnostic lung low-dose CT scanner. Patient characteristics, dose indicators, technical efficacy (minimal margin [MM], recurrence during follow-up), and complications (pneumothorax, alveolar haemorrhage, and haemoptysis) were recorded. We included 61 patients (median age, 65 [54-73] and 33 women), with no significant differences according to the type of protocol, except for the type of anaesthesia. Even if the number of helical acquisitions did not significantly change, all dose indicators significantly decreased by 1.5-fold-3-fold. The median dose-length-product and effective dose, with their ranges, respectively, were 465 mGy cm (315-554) and 6.5 mSv (4.4-7.8) in the SP group versus 178 mGy cm (154-267) and 2.5 mSv (2.2-3.7) in the ULD group, (p< 001). The ULD group exhibited lower intraoperator variability and better interoperator alignment than those of the SP group. The MM was not significantly different between the two groups (4.6 mm versus 5 mm,p= 16). One local recurrence was observed in each group at 8 months in the SP and at one year in the ULD group (p= 1). The complication rates did not differ significantly. Implementing an ULD protocol during lung RFA may provide similar efficacy, a reduction of dose indicators, and intra- and interoperator variability, without increasing complication rates, compared to those associated with an SP.

Computed tomography-guided microwave ablation of perivascular liver metastases from colorectal cancer: a study of the ablation zone, feasibility, and safety.

OBJECTIVES: To compare the ablation margins and safety of microwave ablation (MWA) of perivascular versus non-perivascular liver metastases from colorectal cancer (CRC) and to determine the risk factors for local tumor progression (LTP) after perivascular MWA. METHODS: Between June 2017 and June 2019, 84 metastases were treated: 39 perivascular (<5 mm from a vessel >3 mm), and 46 non-perivascular. Perivascular metastases were treated with either conventional or optimized protocols (maximum power and/or several heating cycles after repositioning the needle regardless of the initial tumor dimensions). The mean diameter of metastases was 15.4 mm (SD: 7.56). RESULTS: Vascular proximity did not result in a significant difference in ablation margins. The technical success rate, primary efficacy, and secondary efficacy were 90%, 66%, and 83%, respectively. Perivascular location was not a risk factor for time to LTP (p = 0.49), RFS (p = 0.52), or OS (p = 0.54). LTP was statistically related to the presence of a colonic obstruction (p < 0.05), number of metastases at the time of diagnosis (p < 0.05), type of protocol (p < 0.05), ablation margins (p < 0.001) and LTP was proportional to the number of liver resections before MWA (p < 0.05). There was no LTP in tumors ablated with margins over 10 mm. Two grade 4 complications occurred. CONCLUSION: MWA is an effective and safe treatment for perivascular liver metastases from CRC, provided that satisfactory margins are achieved. A maximalist attitude could be related to better local control.

Utility of a Suture-Mediated Closure System for Large Bore Arterial Access During Challenging Liver Intra-Arterial Catheters Implantation.

PURPOSE: To describe and study the utility of vascular suture-mediated closure systems for large bore arterial access during challenging implantation of liver intra-arterial catheters taking as a reference the conventional procedure involving patients without challenging anatomy. MATERIALS AND METHODS: Between January 2017 and January 2019, 61 consecutive patients underwent 65 intra-arterial catheter IAC implantations for colorectal cancer. Twenty-three procedures (35%) considered by the operators with challenging coeliac trunk angulations were treated using a vascular suture technique where a 6-F introducer was used, the other patients were treated with a conventional 4F access technique. Clinical and radiological characteristics of patients, technical success (implantation of catheters allowing safe infusion of chemotherapy) and complications (Common Terminology Criteria for Adverse Events, CTCAE 5.0) were recorded. RESULTS: Mean coeliac trunk angulations were 36.3° (± 14.3) for the vascular closure group and 49.6° (± 17.1) for the conventional group. Technical success of the procedures was 100% for the vascular closure group and 80% in the conventional group (p < .05). Four patients with technical failure in the conventional group had a successful IAC implantation on the second attempt using the vascular closure technique. The use of a suture-mediated closure system for large bore arterial access allowed more frequent positioning of the distal tip into the gastro duodenal artery (GDA) (p = .01). No major complication occurred. CONCLUSION: The use of a large bore arterial access combined with a suture-mediated closure system may be useful for challenging IAC implantation without major complications.

A study of dose indicators during intra-arterial catheter implantation for liver chemotherapy.

The aim of the present study was to describe patient dose indicator levels during intra-arterial catheter (IAC) implantation for liver chemotherapy, and to determine factors affecting the dose indicators. Between January 2017 and January 2019, 61 patients with hepatic metastases from colorectal cancer were retrospectively included. Interventions were carried out in a standardised manner by three experienced radiologists on the same angiographic table without changes in protocol parameters. For each patient, clinical, radiological and dosimetry data were collected, including the air kerma area product (KAP), part of KAP due to the fluoroscopy and fluoroscopy time (FT), total kerma at the reference interventional point and peak skin dose (PSD). Local dose reference levels (RLs) were determined as the third quartile of the patient dose distributions. Univariate and multivariate analysis of factors affecting dose indicators was performed. The mean KAP was 111 Gy cm2, the mean reference point air kerma (Ka,r) was 648 mGy, the mean PSD was 613 mGy, and the mean FT was 3190 s (62% of the KAP). The mean cone beam computed tomography dose was 37.3 ± 11.8 Gy cm2, which accounted for 37% of the KAP. The RL could be proposed taking into account the third quartiles (KAP = 164.6 Gy cm2, Ka,r = 904.5 mGy, FT = 4011 s and standard deviation = 772.7 mGy). The factors affecting dose indicators were related to the patients (sex, cardiovascular risk factors, weight, body mass index), to the vascular anatomies (coeliac trunk angulation) and to the procedures (number of embolised arteries). This study allowed a better understanding of dose indicators and factors affecting these indicators during the implantation of IACs for hepatic chemotherapy, which is a long and difficult procedure. Local dose RLs were determined. Multicentre, multi-equipment studies are necessary.

Efficacy of Tract Embolization After Percutaneous Pulmonary Radiofrequency Ablation.

PURPOSE: To evaluate the efficacy of tract embolization technique using gelatin sponge slurry with iodinated contrast medium (GSSI) to reduce the incidence of pneumothorax and chest tube placement after computed tomography-guided lung radiofrequency ablation (RFA). MATERIALS AND METHODS: In this single-institute retrospective study, we examined all patients with metastatic cancer treated from January 2016 to December 2019 by interventional radiologists with computed tomography-guided lung RFA. Since 2017 in our institution, we have applied a tract embolization technique using GSSI for all RFA. Patients were included into those who underwent lung RFA performed either with GSSI (Group A) or without GSSI (Group B). Univariate and multivariate analyses were performed between the two groups to identify risk factors for pneumothorax and chest tube placement, including patient demographics and lesion characteristics. RESULTS: This study included 116 patients (54 men, 62 women; mean age, 65 ± 11 years) who underwent RFA. Group A comprised 71 patients and Group B comprised 45 patients. Patients who underwent tract embolization had a significantly lower incidence of pneumothorax (Group A, 34% vs. Group B, 62%; p < 0.001) and chest tube insertion (Group A, 10% vs. Group B, 29%; p < 0.01). No embolic complications occurred. The hospitalization stay was significantly shorter in patients who underwent tract embolization (mean, 1.04 ± 0.2 days; p = 0.02). CONCLUSION: Tract embolization after percutaneous lung RFA significantly reduced the rate of post-RFA pneumothorax and chest tube placement and was safer than the standard lung RFA technique.

Computed tomography-guided percutaneous cryoablation of T1b renal tumors: safety, functional and oncological outcomes.

Purpose: To evaluate the safety, functional and oncological outcomes associated with percutaneous cryoablation of stage T1b renal cell carcinoma (RCC). Materials and methods: Institutional database was reviewed to identify patients treated by percutaneous CT-guidance cryoablation between 2013 and 2018 for biopsy-proven RCC tumors measuring 4.1-7.0 cm. The main outcome parameters analyzed were primary and secondary technique efficacy, progression-free survival (PFS), cancer-specific survival (CSS), loss of estimated glomerular filtration rate (eGFR) and complications. PFS and CSS were estimated by the Kaplan-Meier method. Complications were graded by the Clavien-Dindo system. Results: Twenty-three consecutive patients were included (mean tumor diameter: 45.6 ± 6.2 mm; mean RENAL score: 8.1 ± 1.8). The technical success rate was 95.7%. Primary and secondary technique efficacy rates were 86.3 and 100%, respectively. Three patients found to have incomplete ablations at 3 months were successfully treated by repeat cryoablation. Median duration follow-up was 11 months (range: 3-33). Imaging showed PFS to be 85.7% at 6 months, 66.7% at 12 months and 66.7% at 24 months. One patient with a local recurrence at 12 months was treated by radical nephrectomy. One patient died from progression of disease within 12 months. One patient reported a complication grade ≥ II (4.3%). Mean eGFR loss was 4.4 ± 8.5 ml/min/1.73m2, which was significantly higher among those treated for central tumors (p < .05). Conclusion: Cryoablation for stage T1b renal tumors is technically feasible, with favorable oncological and perioperative outcomes. Longer-term studies are needed to verify our findings.

Outcomes of Pulmonary Artery Embolization and Stent Graft Placement for the Treatment of Hemoptysis Caused by Lung Tumors.

PURPOSE: To evaluate the safety and efficacy of endovascular management of pulmonary artery lesions caused by lung tumors. MATERIALS AND METHODS: Nineteen patients (15 men, 4 women; average age: 60.3 years, range, 51-86 years) treated for massive or recurrent hemoptysis with transarterial pulmonary artery embolization between 2010 and 2016 were included in this multicenter, retrospective study. Inclusion criteria were: patients with lung cancer and at least 1 episode of hemoptysis with a pulmonary artery lesion detected by computed tomography (CT) angiography or after failed bronchial artery embolization. No patient undergoing pulmonary embolization for a lung tumor was excluded. Technical success, clinical success, and complications were recorded. The survival curve was estimated using the Kaplan-Meier method RESULTS: Mean follow-up was 188.1 days (range, 0-1440 days). Primary and assisted technical success rates were 73.7% (14/19) and 84.2% (16/19), respectively. Two patients died during the procedure due to massive hemoptysis and cardiac arrest, and 1 patient was treated with surgery. All patients with technical success achieved clinical success without further bleeding. No complications were noted, and no pulmonary infarction was detected on CT scan during follow-up. Survival rates after embolization at 1 and 3 months were 67% (95% confidence interval [CI]: 40%-90%) and 46% (95% CI: 23%-80%), respectively, with 36.8% (n = 7) of the patients still alive at the end of the study. CONCLUSIONS: Embolization is an effective and safe treatment of lung tumors with pulmonary arterial bleeding.

Persistent pathways after lung radiofrequency ablation as a risk factor of drain placement.

PURPOSE: The risk factors of pneumothorax after lung radiofrequency (RF) ablation are long known. The objective was to demonstrate that the visualisation of an aeric RF path after the needle withdrawal was predictive of pneumothorax occurrence and chest tube placement. MATERIALS AND METHODS: A total of 70 patients were retrospectively included in this study. For each patient, we determined the pneumothorax risk factors (age, gender, previous surgery, emphysema, lesion size, distance between pleura and lesion), visualisation of a RF track, length and thickness, presence of pneumothorax, volume, chest tube placement, duration of drainage and hospital stay. RESULTS: Among 70 patients included retrospectively, 26 needed a chest tube placement (37%). Considering the group with path visualisation (37 patients, group A) and the patients without path visualisation (group B), the 2 groups were comparable for pneumothorax risk factors. Considering the patients who needed a chest drain, the visualisation of the path was significatively more important (23 cases, 88.4%) (p< 10-3) than in the group without (8 patients, 31.8%). Multivariate analyses were significant in the three analyses after adjustments on the risk factors for the occurrence of pneumothorax. Incidence of drains was significantly more (p < 10-3) important in group A (23 drainages 62%) than in group B (4 drainages or 12%). The length and thickness of the tracks were not predictable of drain placement. CONCLUSIONS: Besides the well-known risk factors of severe pneumothorax after lung RFA, the simple visualisation of an aeric path just after the RF needle withdrawal is significantly associated with chest tube placement and can be considered as a risk factor as itself.

Role of dual-energy computed tomography in detecting early recurrences of lung tumours treated with radiofrequency ablation.

PURPOSE: Detecting a recurrence after lung radiofrequency ablation (RFA) is based on a group of arguments that include CT, positron emission tomography (PET-CT) at 3 months and clinical patient follow-up. There is no one examination that is absolutely reliable. Recurrences are diagnosed tardily, when the cancers are locally extended, or when the patients are metastatic. The purpose of this article is to investigate the utility of dual-energy computed tomography (DECT) in order to assess therapeutic responses to RFA for lung neoplasia. MATERIALS AND METHODS: This institutional review board-approved study enroled 70 patients with lung tumours who underwent DECT after RFA. All patients provided a written informed consent for the study. RESULTS: The study included 70 consecutive patients, and 191 DECT measures were performed. We collected the enhancement values of all scars without establishing a prior threshold of positivity. The optimal threshold value areas appeared to be located between 20 and 35 Hounsfield unit (HU) with sensitivity between 70% and 82%; specificity between 72% and 90%; a negative predictive value (NPV) between 96% and 97% and a diagnostic accuracy index between 73% and 87%. At the one month follow-up, 53 nodules were analysed with DECT and four nodules had recurred, all of which were detected by DECT. The sensitivity, which was calculated at 100%, was excellent; the NPV was at 100% (CI: 91.62, 100) and the specificity was at 85.71% (CI: 73.33, 92.9). The diagnostic accuracy index was 86.79% (CI: 75.16, 93.45) and the average DECT acquisitions dosimetry was 106 mGy.cm (33mGy.cm 245mGy.cm). CONCLUSION: DECT could be a conceivable alternative for detecting early recurrence after lung RFA. Key points After lung RFA, a PET CT has a high rate of false positives in the initial phase; The study of enhancement in the follow-up of lung lesions treated with RFA, and especially by DECT, can be relevant; Dual Energy CT has a good efficiency for a threshold between 20 and 35 HU, especially in the first month after RFA; DECT could be a conceivable alternative for detecting early recurrence.

Pathological effects of lung radiofrequency ablation that contribute to pneumothorax, using a porcine model.

OBJECTIVES: The incidence of pneumothorax is 7 times higher after lung radiofrequency ablation (RFA) than after lung biopsy. The reasons for such a difference have never been objectified. The histopathologic changes in lung tissue are well-studied and established for RF in the ablation zone. However, it has not been previously described what the nature of thermal injury might be along the shaft of the RF electrode as it traverses through normal lung tissue to reach the ablation zone. The purpose of this study was to determine the changes occurring around the RF needle along the pathway between the ablated zone and the pleura. MATERIAL AND METHODS: In 3 anaesthetised and ventilated swine, 6 RFA procedures (right and left lungs) were performed using a 14-gauge unipolar multi-tined retractable 3 cm radiofrequency LeVeen probe with a coaxial introducer positioned under CT fluoroscopic guidance. In compliance with literature guidelines, we implemented a gradually increasing thermo-ablation protocol using a RF generator. Helical CT images were acquired pre- and post-RFA procedure to detect and evaluate pneumothorax. Four percutaneous 19-gauge lung biopsies were also performed on the fourth swine under CT guidance. Swine were sacrificed for lung ex vivo examinations, scanning electron microscopy (SEM) and pathological analysis. RESULTS: Three severe (over 50 ml) pneumothorax were detected after RFA. In each one of them, pathological examination revealed a fistulous tract between ablation zone and pleura. No fistulous tract was observed after biopsies. In the 3 cases of severe pneumothorax, the tract was wide open and clearly visible on post procedure CT images and SEM examinations. The RFA tract differed from the needle biopsy tract. The histological changes that are usually found in the ablated zone were observed in the RFA tract's wall and were related to thermal lesions. These modifications caused the creation of a coagulated pulmonary parenchyma rim between the thermo-ablation zone and the pleural space. The structural properties of the damage can explain why the RFA tract is remains patent after needle withdrawal. CONCLUSION: Our study demonstrates for the first time that the changes around the RF needle are the same as in the ablated zone. The damage could create fistulous tracts along the needle path between thermo-ablation zone and pleural space. These fistulas could certainly be responsible for severe pneumothorax that occurs in many patients treated with lung RFA.

Embolisation of pulmonary radio frequency pathway - a randomised trial.

PURPOSE: Pneumothorax is the most common complication following a pulmonary percutaneous radiofrequency ablation (RFA), and thoracic drainages are the most frequent causes of an extended hospital stay. Our main objective was to show that the use of gelatin torpedoes may significantly decrease the number of chest tube placement. MATERIALS AND METHODS: Seventy-three patients were prospectively included in this study and then randomised into two groups: 34 with embolisation and without 39 without embolisation. Each group was comparable for different pneumothorax risk factors. RESULTS: There were 16 (47%) pneumothorax in Group A ("with embolisation"), which was significantly lower (p < .0001) than the 35 pneumothorax (90%) in Group B ("without embolisation"). The pneumothorax volume (p = .02) was significantly lower in Group A (22.7% average, standard deviation 15.6%) than in Group B (average 34.1%, standard deviation 17.1%). The number of drainages was significantly smaller in those with embolisation (3 drainages or 8%) than those without embolisation (25 drainages or 64%) (p < .001). CONCLUSION: When using absorbable gelatin torpedoes, pulmonary RFA pathways embolisation significantly decreased the number of pneumothorax and thoracic drainages to the advantage of therapeutic abstention and exsufflation, non-invasive and functional operational techniques.