In vivo evaluation of tumor uptake and bio-distribution of 99mTc-labeled 1-thio-ß-D-glucose and 5-thio-D-glucose in mice model.

BACKGROUND: To investigate the capacity of 99mTc-labeled 1-thio-ß-D-glucose (1-TG) and 5-thio-D-glucose (5-TG) to act as a marker for glucose consumption in tumor cells in vivo as well as to evaluate the biodistribution of 1-TG and 5-TG. We investigated the biodistribution, including tumor uptake, of 1-TG and 5-TG at various time points after injection (0.5, 2 and 4 h) in human colorectal carcinoma (HCT-116) and human lung adenocarcinoma (A549) xenograft bearing nude mice (N = 4 per tracer and time point). RESULTS: Ex vivo biodistribution studies revealed a moderate uptake with a maximum tumor-to-muscle ratio of 4.22 ± 2.7 and 2.2 ± 1.3 (HCT-116) and of 3.2 ± 1.1 and 4.1 ± 1.3 (A549) for 1-TG and 5-TG, respectively, with a peak at 4 h for 1-TG and 5-TG. Biodistribution revealed a significantly higher uptake compared to blood in kidneys (12.18 ± 8.77 and 12.69 ± 8.93%ID/g at 30 min) and liver (2.6 ± 2.8%ID/g) for 1-TG and in the lung (7.24 ± 4.1%ID/g), liver (6.38 ± 2.94%ID/g), and kidneys (4.71 ± 1.97 and 4.81 ± 1.91%ID/g) for 5-TG. CONCLUSIONS: 1-TG and 5-TG showed an insufficient tumor uptake with a moderate tumor-to-muscle ratio, not reaching the levels of commonly used tracer, for diagnostic use in human colorectal carcinoma and human lung adenocarcinoma xenograft model.

Patient-related benefits of amyloid PET imaging in dementia: Rationale and design of the German randomized coverage with evidence development study ENABLE.

The utility of amyloid positron emission tomography (PET) for the etiological diagnosis of dementia and its impact on functional status of patients in routine care are currently unclear. Here, we describe the design of ENABLE, a randomized controlled two-armed coverage with evidence development (CED) study in Germany. Approximately 1126 patients with mild to moderate dementia of unclear etiology will be randomly assigned to either an amyloid PET or a no amyloid PET group. Patients will be followed-up for 24 months. The study has been registered at the German Clinical Trials Register (https://drks.de/search/de/trial/DRKS00030839) with the registration code DRKS00030839. The primary endpoint of ENABLE is the ability to perform functional activities of daily living at 18 months. Secondary endpoints include change in diagnosis, diagnostic confidence, and cognitive and clinical outcomes of patients. We expect that the CED study ENABLE will inform about patient relevant effects of amyloid PET in routine care. Furthermore, we anticipate that ENABLE will support physicians' and payers' decisions on provision of health care for patients with dementia. Highlights: Study design focuses on the usefulness of amyloid positron emission tomography (PET) in routine care.Study design addresses the patient-relevant effect of amyloid PET.Patient representatives were involved in the creation of the study design.The study will help improve routine care for people with dementia.

Multidisciplinary Treatment of Patients with Progressive Biliary Tract Cancer after First-Line Gemcitabine and Cisplatin: A Single-Center Experience.

BACKGROUND: Patients with unresectable biliary tract cancer (uBTC) who progress despite first-line gemcitabine plus cisplatin (GC) treatment have limited systemic options with a modest survival benefit. Data are lacking on the clinical effectiveness and safety of personalized treatment based on multidisciplinary discussion for patients with progressing uBTC. METHODS: This retrospective single-center study included patients with progressive uBTC who received either best supportive care or personalized treatment based on multidisciplinary discussion, including minimally invasive, image-guided procedures (MIT); FOLFIRI; or both (MIT and FOLFIRI), between 2011 and 2021. RESULTS: Ninety-seven patients with progressive uBTC were identified. Patients received best supportive care (n = 50, 52%), MIT (n = 14, 14%), FOLFIRI (n = 19, 20%), or both (n = 14, 14%). Survival after disease progression was better in patients who received MIT (8.8 months; 95% CI: 2.60-15.08), FOLFIRI (6 months; 95% CI: 3.30-8.72), or both (15.1 months; 95% CI: 3.66-26.50) than in patients receiving BSC (0.36 months; 95% CI: 0.00-1.24, p < 0.001). The most common (>10%) grade 3-5 adverse events were anemia (25%) and thrombocytopenia (11%). CONCLUSION: Multidisciplinary discussion is critical for identifying patients with progressive uBTC who might benefit the most from MIT, FOLFIRI, or both. The safety profile was consistent with previous reports.

Correlation of PET-MRI, Pathology, LOH, and Surgical Success in a Case of CHI With Atypical Large Pancreatic Focus.

Congenital hyperinsulinism (CHI) is a rare cause of severe hypoglycemia in newborns. In focal CHI, usually one activity peak in fluorine-18-L-dihydroxyphenylalanine (18F-DOPA) positron emission tomography-magnetic resonance imaging (PET-MRI) indicates one focal lesion and its resection results in cure of the child. We present the case of a 5-month-old girl with CHI. Mutational screening of genes involved in CHI revealed a heterozygous pathogenic variant in the ABCC8 gene, which was not detectable in the parents. 18F-DOPA PET-MRI revealed 2 distinct activity peaks nearby in the pancreatic body and neck. Surgical resection of the tissue areas representing both activity peaks resulted in long-lasting normoglycemia that was proven by a fasting test. Molecular analysis of tissue samples from various sites provided evidence that a single second genetic hit in a pancreatic precursor cell was responsible for the atypical extended pancreatic lesion. There was a close correlation in the resected areas of PET-MRI activity with focal histopathology and frequency of the mutant allele (loss of heterozygosity) in the tissue. Focal lesions can be very heterogenous. The resection of the most affected areas as indicated by imaging, histopathology, and genetics could result in complete cure.

Interstitial High-Dose-Rate Brachytherapy of Liver Metastases in Oligometastatic Patients.

Local ablative treatments have emerged as a promising treatment strategy for patients with oligometastatic disease. Among others, interstitial brachytherapy (iBT) is an upcoming treatment option for unresectable liver metastases. We report the feasibility and oncologic outcome of iBT of oligometastatic liver metastases performed in patients with limited tumor burdens in a high-volume center. Patients undergoing iBT between August 2017and March 2019 were included. A retrospective analysis of patient outcomes and treatment complications was performed. Patients treated for metastatic colorectal carcinoma (CRC) were compared to other histologies. A total of 141 iBT procedures were performed in 106 patients (male:52; female:54) and 244 liver metastases. Overall, 51% (54/106) of patients had a diagnosis of metastatic CRC. The median follow-up was 9 months, and overall survival (OS) was 92.3% at 6 months and 76.3% at 12 months. Local-relapse-free survival (LRFS) was 88.4% at 6 months and 71.5% at 12 months, with a significant difference between patients with CRC (84.1% and 50.6%) versus other histologies (92.4% and 92.4%, p < 0.001). A sub-group analysis showed a significant advantage in patients with CRC receiving a minimal dose (D100) of 20 Gy to the planning target volume. Treatments of smaller total liver-tumor volumes (<18 ccm) resulted in better LRFS rates. iBT is a safe and effective treatment approach for oligometastatic liver disease. A higher treatment dose is needed for patients with CRC. Moreover, lower metastatic burdens may be favorable for LRFS. Prospective studies are needed to assess the role of iBT in the oligometastatic setting as an alternative to other local ablative treatment approaches in patients with liver metastases.

Technical aspects of paediatric robotic pancreatic enucleation based on a case of an insulinoma.

BACKGROUND: Insulinomas are rare insulin-producing pancreatic neuroendocrine tumours leading to severe episodes of hypoglycaemia. Surgery is the predominant curative therapy. METHODS: We report here the first paediatric case of an insulinoma of the pancreatic body resected completely robotically under ultrasound guidance in a 10-year-old male with multiple endocrine neoplasia type 1. The port set-up was adapted for the narrowed dimensions of the paediatric peritoneal space. We comment on technical key steps for the organ-preserving procedure that was performed in close proximity to critical anatomic structures, with supporting video. Preoperative diagnostics, including endoscopic ultrasound, to determine surgical management are highlighted. RESULTS: Following an uneventful post-operative course, the boy was discharged on day 11 with normalised glucose-metabolism. A pseudocyst developing after 4 weeks was treated with endoscopic stenting. CONCLUSIONS: The applicability of a robotic surgical system in limited space conditions such as found in the paediatric abdominal cavity is demonstrated here for pancreatic surgery.

Comparative analysis between interstitial brachytherapy and stereotactic body irradiation for local ablation in liver malignancies.

PURPOSE: Interstitial high-dose-rate brachytherapy (BT) is an alternative treatment option to stereotactic body radiotherapy (SBRT) for the ablative treatment of liver malignancies. The aim of the present comparative planning study was to reveal the possibilities and limitations of both techniques with regard to dosimetric properties. METHODS AND MATERIALS: Eighty-five consecutive patients with liver malignancy diagnosis were treated with interstitial BT between 12/2008 and 09/2009. The prescription dose of BT varied between 15 and 20 Gy, depending on histology. For dosimetric comparison, virtual SBRT treatment plans were generated using the original BT planning CTs. Additional margins reflecting the respiratory tumor motion were added to the target volumes for SBRT planning. RESULTS: The mean PTVBT was 34.7 cm3 (0.5-410.0 cm3) vs. a mean PTVSBRT of 73.2 cm3 (6.1-593.4 cm3). Regarding the minimum peripheral dose (D99.9), BT achieved the targeted prescription dose of 15 Gy/20 Gy better without violating organ at risk constraints. The dose exposure of the liver was significantly influenced by treatment modality. The liver exposure to 5 Gy was statistically lower with 611 ± 43 cm3 for BT as compared with 694 ± 37 cm3 for SBRT plans (20-Gy group, p = 0.001), corresponding to 41.8% vs. 45.9% liver volume, respectively. CONCLUSIONS: To the best of our knowledge, this is the first report on the comparison of clinically treated liver BT treatments with virtually planned SBRT treatments. The planning study showed a superior outcome of BT regarding dose coverage of the target volume and exposed liver volume. Nevertheless, further studies are needed to determine ideal applicability for each treatment approach.

First report on extended distance between tumor lesion and adjacent organs at risk using interventionally applied balloon catheters: a simple procedure to optimize clinical target volume covering effective isodose in interstitial high-dose-rate brachytherapy of liver malignomas.

PURPOSE: Organs at risk (OARs), which are very close to a clinical target volume (CTV), can compromise effective tumor irradiation. The present study investigated the feasibility and safety of a novel approach, in particular, the extent of the dosimetric effect of distancing CTV from adjacent OARs by means of interventionally applied balloon catheters. MATERIAL AND METHODS: Patients with peripheral hepatic malignancies, in whom the critical proximity of an OAR to the CTV in the assessment by contrast-enhanced magnetic resonance imaging (MRI) scans and the preplanning process were included. Additionally, patients underwent placement of an interventional balloon catheter during computed tomography (CT)-guided application of interstitial brachytherapy (iBT) catheters inserted into the tissue between hepatic capsule and adjacent OAR. The virtual position of an OAR without balloon catheter was anticipated and contoured in addition to contouring of CTV and OAR. The calculated dose values for CTV as well as 1 cc of the relevant OAR (D1cc) with and without balloon were recorded. The D1cc of the realized irradiation plan was statistically compared to the D1cc of the virtually contoured OARs. RESULTS: In 31 cases, at least one balloon catheter was administered. The mean D1cc of the OAR in the group with balloon(s) was 12.6 Gy compared with 16 Gy in the virtual cohort without the device, therefore significantly lower (p < 0.001). Overall, there were no acute complications. Severe (> 2 CTCAEv4.03) late complications observed in 3/31 (9.6%) patients during follow-up period after brachytherapy were most certainly not due to the balloon application. Side effects were probably associated with pre-existing serious diseases and potentially additional local late effects of the irradiation in general rather than with the balloon catheters. CONCLUSIONS: The distancing of the adjacent OARs allows a higher D100 value of CTV, therefore allowing for more efficient local control.

Efficacy and safety of CT-guided high-dose-rate interstitial brachytherapy in primary and secondary malignancies of the pancreas.

PURPOSE: To evaluate efficacy and safety of CT-guided iBT in patients with primary and secondary malignancies of the pancreas. MATERIAL AND METHODS: 13 patients with 13 lesions of the pancreatic corpus and tail were included: 8 secondary malignancies (metastatic lesions = ML) and 5 primary malignancies, including 3 primary tumors (PT) and 2 isolated locoregional recurrences (ILR) after surgical resection were treated with image-guided iBT using a 192iridium source (single fraction irradiation). Every 3 months after treatment clinical and imaging follow-up were conducted to evaluate efficacy. Peri- and postinterventional complications were assessed descriptively. RESULTS: The median diameter of the gross tumor volume (GTV) was 3 cm (range 1-6.5 cm), treated with a median D100 (minimal enclosing tumor dose) of 15.3 Gy (range 9.2-25.4 Gy). Local tumor control (LTC) was 92.3% within a median follow-up period of 6.7 months (range 3.2-55.7 months). Cumulative median progression free survival (PFS) was 6.2 months (range 2.8-25.7 months; PFS of primary and secondary malignancies was 5.8 and 6.2 months, respectively). Cumulative median over all survival (OS) after iBT was 16.2 months (range 3.3-55.7 months; OS of primary and secondary malignancies was 7.4 months and 45.6 months, respectively). 1 patient developed mild acute pancreatits post iBT, spontanously resolved within 1 week. No severe adverse events (grade 3+) were recorded. CONCLUSION: Image-guided iBT is a safe and particularly effective treatment in patients with primary and secondary malignancies of the pancreas and might provide a well-tolerated additional therapeutic option in the multidisciplinary management of selected patients.

Biliary duct stenosis after image-guided high-dose-rate interstitial brachytherapy of central and hilar liver tumors : A systematic analysis of 102 cases.

OBJECTIVE: Image-guided high-dose-rate interstitial brachytherapy (iBT) with iridium-192 is an effective treatment option for patients with liver malignancies. Little is known about long-term radiation effects on the bile duct system when central hepatic structures are exposed to iBT. This retrospective analysis investigates the occurrence of posthepatic cholestasis (PHC) and associated complications in patients undergoing iBT. MATERIALS AND METHODS: We identified patients who underwent iBT of hepatic malignancies and had point doses of ≥1 Gy to central bile duct structures. Patients with known bile duct-related diseases or prior bile duct manipulation were excluded. RESULTS: 102 patients were retrospectively included. Twenty-two patients (22%) developed morphologic PHC after a median of 17 (3-54) months; 18 of them were treated using percutaneous transhepatic cholangiopancreatography drainage or endoscopic retrograde cholangiopancreatography. The median point dose was 24.8 (4.4-80) Gy in patients with PHC versus 14.2 (1.8-61.7) Gy in those without PHC (p = 0.028). A dose of 20.8 Gy (biological effective dose, BED3/10 = 165/64.1 Gy) was identified to be the optimal cutoff dose (p = 0.028; 59% sensitivity, 24% specificity). Abscess/cholangitis was more common in patients with PHC compared to those without (4 of 22 vs. 2 of 80; p = 0.029). Median survival did not differ between patients with and without PHC (43 vs. 36 months; p = 0.571). CONCLUSION: iBT of liver malignancies located near the hilum can cause PHC when the central bile ducts are exposed to high point doses. Given the long latency and absence of impact of iBT-induced PHC on median survival, the rate of cholestasis and complications seen in our patients appears to be acceptable.

Treatment of metastatic, imatinib refractory, gastrointestinal stroma tumor with image-guided high-dose-rate interstitial brachytherapy.

PURPOSE: Evaluation of efficacy and safety of CT- or MRI-guided high-dose-rate interstitial brachytherapy (iBT) in the treatment of advanced, imatinib refractory, metastatic gastrointestinal stroma tumors (GISTs) was the objective of this retrospective study. METHODS AND MATERIALS: A cumulative number of 40 unresectable metastases (30 hepatic, 10 peritoneal) were treated with iBT in 10 selected patients with histologically proven GISTs. Six patients had peritoneal disease, and 5 patients were even progressing under sunitinib (second line)-thus iBT was applied as a salvage maneuver. IBT uses an interstitially introduced 192iridium source in a high-dose-rate irradiation regime to destroy vital cells in a single fraction. Response to treatment was assessed clinically and with acquisition of MRI/CT every 3 months. RESULTS: Local tumor control was reached in 97.5% of all treated metastases during a median time of 25 months-only one local relapse was observed during followup. The median diameter of the irradiated lesions was 2.4 cm (range 0.6-11.2 cm); a median dose of 15 Gy (range 6.7-21.96 Gy) was applied. The median progression-free survival after iBT was 6.8 (range 3.0-20.2) months; the median overall survival was 37.3 months (range 11.4-89.7). Two major complications (Common Terminology for Adverse Events grade 3) occurred following the intervention: local hemorrhage and pneumothorax, successfully dealt with by angiographic embolization and pleural drainage, respectively. CONCLUSIONS: In selected patients with metastatic, imatinib refractory GISTs, iBT safely enables high rates of local tumor control and presents an alternative, anti-neoplastic treatment option even in a salvage situation.

Radioablation by Image-Guided (HDR) Brachytherapy and Transarterial Chemoembolization in Hepatocellular Carcinoma: A Randomized Phase II Trial.

BACKGROUND AND AIMS: The aim of this single-center, open-label phase II study was to assess the efficacy of image-guided high-dose-rate (HDR) brachytherapy (iBT) compared with conventional transarterial embolization (cTACE) in unresectable hepatocellular carcinoma. METHODS: Seventy-seven patients were treated after randomization to iBT or cTACE, as single or repeated interventions. Crossover was allowed if clinically indicated. The primary endpoint was time to untreatable progression (TTUP). Eligibility criteria included a Child-Pugh score of ≤ 8 points, absence of portal vein thrombosis (PVT) at the affected liver lobe, and ≤ 4 lesions. Survival was analyzed by using the Cox proportional hazard model with stratification for Barcelona Clinic Liver Cancer (BCLC) stages. RESULTS: Twenty patients were classified as BCLC-A (iBT/cTACE 8/12), 35 as BCLC-B (16/19), and 22 as BCLC-C (13/9). The 1-, 2-, and 3-year TTUP probabilities for iBT compared with cTACE were 67.5% versus 55.2%, 56.0% versus 27.4%, and 29.5% versus 11.0%, respectively, with an adjusted hazard ratio (HR) of 0.49 (95% confidence interval 0.27-0.89; p = 0.019). The 1-, 2-, and 3-year TTPs for iBT versus cTACE were 56.0% versus 28.2%, 23.9% versus 6.3%, and 15.9% versus 6.3%, respectively, with an adjusted HR of 0.49 (0.29-0.85; p = 0.011). The 1-, 2-, and 3-year OS rates were 78.4% versus 67.7%, 62.0% versus 47.3%, and 36.7% versus 27.0%, respectively, with an adjusted HR of 0.62 (0.33-1.16; p = 0.136). CONCLUSIONS: This explorative phase II trial showed a superior outcome of iBT compared with cTACE in hepatocellular carcinoma and supports proceeding to a phase III trial.

Local ablation or radioembolization of colorectal cancer metastases: comorbidities or older age do not affect overall survival.

BACKGROUND: Local ablative techniques are emerging in patients with oligometastatic disease from colorectal carcinoma, commonly described as less invasive than surgical methods. This single arm cohort seeks to determine whether such methods are suitable in patients with comorbidities or higher age. METHODS: Two hundred sixty-six patients received radiofrequency ablation (RFA), CT-guided high-dose rate brachytherapy (HDR-BT) or Y90-radioembolization (Y90-RE) during treatment of metastatic colorectal cancer (mCRC). This cohort comprised of patients with heterogenous disease stages from single liver lesions to multiple organ systems involvement commonly following multiple chemotherapy lines. Data was reviewed retrospectively for patient demographics, previous therapies, initial or disease stages at first intervention, comorbidities and mortality. Comorbidity was measured using the Charlson Comorbidity Index (CCI) and age-adjusted Charlson Index (CACI) excluding mCRC as the index disease. Kaplan-Meier survival analysis and Cox regression were used for statistical analysis. RESULTS: Overall median survival of 266 patients was 14 months. Age ≥ 70 years did not influence survival after local therapies. Similarly, CCI or CACI did not affect the patients prognoses in multivariate analyses. Moderate or severe renal insufficiency (n = 12; p = 0.005) was the only single comorbidity identified to negatively affect the outcome after local therapy. CONCLUSION: Interventional procedures for mCRC may be performed safely even in elderly and comorbid patients. In severe renal insufficiency, the use of invasive techniques should be limited to selected cases.

Percutaneous radiofrequency ablation in the treatment of pulmonary malignancies: efficacy, safety and predictive factors.

PURPOSE: The purpose of this study was to evaluate the efficacy, safety and predictive factors of RFA of primary and secondary lung malignancies. PATIENTS AND METHODS: 79 patients with 129 primary and secondary lung malignancies were enrolled in a retrospective study. We treated 74 pulmonary metastases of colorectal cancer, 13 malignant melanoma lesions, 13 renal cancer metastases, 5 primary lung malignancies and 24 tumors of other different entities. All patients were considered to be unsuitable candidates for surgery, radiotherapy or chemotherapy. The primary endpoint was local tumor control, secondary endpoints were overall survival, safety and predictive factors, e.g. distance to pleura, vessels and bronchi. RESULTS: The median tumor size was 1.2 cm (0.5-3.0 cm). After a median follow-up of 14 months (3-81 months), the LTC was 85.3 %. There were 34 lesions (26.4%) with complete remission, 48 (37.2 %) partial remission, 28 (21.7%) stable disease and 19 lesions (14.7%) with progressive disease. We evaluated an OS of 27 months. Pneumothorax in 19 cases (14.7%) and pleural effusion in 2 cases (1.6 %) were the leading complications (CTCAE, 5 grade III adverse events). The only significant influence regarding the outcome after RFA was the initial tumor size (p = 0.01). Distance to vessel, bronchi, and pleura showed no significant effect (p = 0.81; p = 0.82; p = 0.80).

Needle track seeding in hepatocellular carcinoma after local ablation by high-dose-rate brachytherapy: a retrospective study of 588 catheter placements.

PURPOSE: Needle track seeding in the local treatment of hepatocellular carcinoma (HCC) is not yet evaluated for catheter-based high-dose-rate brachytherapy (HDR-BT), a novel local ablative technique. MATERIAL AND METHODS: We report a retrospective analysis of 100 patients treated on 233 HCC lesions by HDR-BT (using 588 catheters in total). No needle or catheter track irradiation was used. Minimum required follow-up with imaging was 6 months. In case of suspected needle track seeding (intra- and/or extrahepatic) in follow-up, image fusion of follow-up CT/MRI with 3D irradiation plan was used to verify the location of a new tumor deposit within the path of a brachytherapy catheter at the time of treatment. RESULTS: We identified 9 needle track metastases, corresponding to a catheter-based risk of 1.5% for any location of occurrence. A total of 7 metastases were located within the liver (catheter-based risk, 1.2%), and 2 metastases were located extrahepatic (catheter-based risk, 0.3%). Eight out of 9 needle track metastases were successfully treated by further HDR-BT. CONCLUSIONS: The risk for needle track seeding after interstitial HDR-BT of HCC is comparable to previous reports of percutaneous biopsies and radiofrequency ablation (RFA), especially in case of extrahepatic needle track metastases. To compensate for the risk of seeding, a track irradiation technique similar to track ablation in RFA should be implemented in clinical routine.

Cytokines and 90Y-Radioembolization: Relation to Liver Function and Overall Survival.

BACKGROUND: To evaluate the course of pro- and anti-inflammatory cytokines after 90Y-radioembolization (RE) of liver malignancies and to identify prognosticators for liver-related adverse events and survival. METHODS: In 34 consecutive patients with secondary or primary liver tumors scheduled for RE, the following cytokines were measured prior to and 2 h, 3 days, and 6 weeks after RE: interleukin (IL) -1, IL-2, IL-4, IL-6, IL-8, tumor necrosis factor alpha (TNF-α), and interferon-γ. Liver function impairment was defined as an elevation of liver-related laboratory values as graded by CTCAE ≥ 2 and/or serum bilirubin ≥30 µmol/l and/or development of ascites at 6-week follow-up. RESULTS: Significant changes over time were seen in IL-1 (increase from 0.4 pg/ml (±0.7) at baseline to 1.1 pg/ml (±1.4) 3 days after RE (p = 0.02)), and in IL-6 (increase from 16.8 pg/ml (±21.8) at baseline to 54.6 pg/ml (±78.2) 3 days after RE (p = 0.003)). Baseline values of IL-6 and IL-8 were independently associated with liver function impairment at follow-up as well as decreased survival with an optimal cutoff at 6.53 and 60.8 pg/ml, respectively. CONCLUSION: Expected changes in pro- and anti-inflammatory cytokines after RE were shown. Furthermore, baseline values of IL-6 and IL-8 were associated with later liver dysfunction and survival. We hypothesize that these biomarkers are potential prognosticators and might help in patient selection for RE.

Improvement of image quality and dose management in CT fluoroscopy by iterative 3D image reconstruction.

OBJECTIVES: The objective of this study was to assess the influence of an iterative CT reconstruction algorithm (IA), newly available for CT-fluoroscopy (CTF), on image noise, readers' confidence and effective dose compared to filtered back projection (FBP). METHODS: Data from 165 patients (FBP/IA = 82/74) with CTF in the thorax, abdomen and pelvis were included. Noise was analysed in a large-diameter vessel. The impact of reconstruction and variables (e.g. X-ray tube current I) influencing noise and effective dose were analysed by ANOVA and a pairwise t-test with Bonferroni-Holm correction. Noise and readers' confidence were evaluated by three readers. RESULTS: Noise was significantly influenced by reconstruction, I, body region and circumference (all p ≤ 0.0002). IA reduced the noise significantly compared to FBP (p = 0.02). The effect varied for body regions and circumferences (p ≤ 0.001). The effective dose was influenced by the reconstruction, body region, interventional procedure and I (all p ≤ 0.02). The inter-rater reliability for noise and readers' confidence was good (W ≥ 0.75, p < 0.0001). Noise and readers' confidence were significantly better in AIDR-3D compared to FBP (p ≤ 0.03). Generally, IA yielded a significant reduction of the median effective dose. CONCLUSION: The CTF reconstruction by IA showed a significant reduction in noise and effective dose while readers' confidence increased. KEY POINTS: • CTF is performed for image guidance in interventional radiology. • Patient exposure was estimated from DLP documented by the CT. • Iterative CT reconstruction is appropriate to reduce image noise in CTF. • Using iterative CT reconstruction, the effective dose was significantly reduced in abdominal interventions.

Improvement of Contrast Media Enhancement in CTA Evaluating Pulmonary Embolism by Utilizing 'Delayed' Bolus Tracking in the Descending Aorta.

BACKGROUND: As standard bolus triggering in the pulmonary trunk sometimes fails to achieve sufficient enhancement in the pulmonary arteries, the study investigates an alternative, 'delayed' position of the tracking ROI in the descending aorta. MATERIAL/METHODS: Retrospective analysis of 143 patients suspected of pulmonary embolism investigated with 3 different scanners (16 to 80 rows) in clinical routine. Bolus triggering with 120 hounsfield units (HU) was performed using the pulmonary trunk (n=70) or descending aorta (n=73) after application of 70 to 120 mL of contrast agent, Iomeprol 300. Student's t-test was applied to compare vascular enhancement. Additional factors were analysed by a regression analysis. RESULTS: Positioning of the tracking ROI in the descending aorta achieved a significantly higher contrast enhancement in the pulmonary trunk with a mean increase of 63 HU (p<0.001). CONCLUSIONS: In CTA, delayed acquisition by using the descending aorta for bolus triggering can improve the enhancement of the pulmonary trunk to investigate a pulmonary embolism. Furthermore, the scan protocol simultaneously allows to rule out aortic pathologies as an alternative cause for a similar clinical condition.

Haemorrhagic Complications and Symptomatic Venous Thromboembolism in Interventional Tumour Ablations: The Impact of Peri-interventional Thrombosis Prophylaxis.

AIM: The aim of this study was to assess the rates of haemorrhagic and thrombotic complications in patients undergoing interventional tumour ablation with and without peri-interventional low-molecular-weight heparin (LMWH) thrombosis prophylaxis. METHODS: Patients presented with primary and secondary neoplastic lesions in the liver, lung, kidney, lymph nodes and other locations. A total of 781 tumour ablations (radiofrequency ablation, n = 112; interstitial brachytherapy, n = 669) were performed in 446 patients over 22 months; 260 were conducted under peri-interventional thrombosis prophylaxis with LMWH (H-group;) and 521 without this (NH-group, in 143 of these, LMWH was given post-interventionally). RESULTS: Sixty-three bleeding events occurred. There were significantly more bleedings in the H-group than in the NH-group (all interventions, 11.66 and 6.26 %, p = 0.0127; liver ablations, 12.73 and 7.1 %, p = 0.0416). The rate of bleeding events Grade ≥ III in all procedures was greater by a factor of >2.6 in the H-group than in the NH-group (4.64 and 1.73 %, p = 0.0243). In liver tumour ablations, the corresponding factor was about 3.3 (5.23 and 1.54 %, p = 0.028). In uni- and multivariate analyses including covariates, the only factor constantly and significantly associated with the rate of haemorrhage events was peri-interventional LMWH prophylaxis. Only one symptomatic lung embolism occurred in the entire cohort (NH-group). The 30- and 90-day mortalities were significantly greater in the H-group than in the NH-group. CONCLUSIONS: Peri-interventional LMWH thrombosis prophylaxis should be considered with caution. The rate of clinically relevant thrombotic events was extremely low.