Utility of pre-procedural [99mTc]TcMAA SPECT/CT Multicompartment Dosimetry for Treatment Planning of 90Y Glass microspheres in patients with Hepatocellular Carcinoma: comparison of anatomic versus [99mTc]TcMAA-based Segmentation.

PURPOSE: Pre-treatment [99mTc]TcMAA-based radioembolization treatment planning using multicompartment dosimetry involves the definition of the tumor and normal tissue compartments and calculation of the prescribed absorbed doses. The aim was to compare the real-world utility of anatomic and [99mTc]TcMAA-based segmentation of tumor and normal tissue compartments. MATERIALS AND METHODS: Included patients had HCC treated by glass [90Y]yttrium microspheres, ≥ 1 tumor, ≥ 3 cm diameter and [99mTc]TcMAA SPECT/CT imaging before treatment. Segmentation was performed retrospectively using dedicated dosimetry software: (1) anatomic (diagnostic CT/MRI-based), and (2) [99mTc]TcMAA threshold-based (i.e., using an activity-isocontour threshold). CT/MRI was co-registered with [99mTc]TcMAA SPECT/CT. Logistic regression and Cox regression, respectively, were used to evaluate relationships between total perfused tumor absorbed dose (TAD) and objective response rate (ORR) and overall survival (OS). In a subset-analysis pre- and post-treatment dosimetry were compared using Bland-Altman analysis and Pearson's correlation coefficient. RESULTS: A total of 209 patients were enrolled. Total perfused tumor and normal tissue volumes were larger when using anatomic versus [99mTc]TcMAA threshold segmentation, resulting in lower absorbed doses. mRECIST ORR was higher with increasing total perfused TAD (odds ratio per 100 Gy TAD increase was 1.22 (95% CI: 1.01-1.49; p = 0.044) for anatomic and 1.19 (95% CI: 1.04-1.37; p = 0.012) for [99mTc]TcMAA threshold segmentation. Higher total perfused TAD was associated with improved OS (hazard ratio per 100 Gy TAD increase was 0.826 (95% CI: 0.714-0.954; p = 0.009) and 0.847 (95% CI: 0.765-0.936; p = 0.001) for anatomic and [99mTc]TcMAA threshold segmentation, respectively). For pre- vs. post-treatment dosimetry comparison, the average bias for total perfused TAD was + 11.5 Gy (95% limits of agreement: -227.0 to 250.0) with a strong positive correlation (Pearson's correlation coefficient = 0.80). CONCLUSION: Real-world data support [99mTc]TcMAA imaging to estimate absorbed doses prior to treatment of HCC with glass [90Y]yttrium microspheres. Both anatomic and [99mTc]TcMAA threshold methods were suitable for treatment planning. TRIAL REGISTRATION NUMBER: NCT03295006.

Quantitative T2 Mapping of Acute Pancreatitis.

BACKGROUND: Quantification of the T2 signal by means of T2 mapping in acute pancreatitis (AP) has the potential to quantify the parenchymal edema. Quantitative T2 mapping may overcome the limitations of previously reported scoring systems for reliable assessment of AP. PURPOSE: To evaluate MR-derived pancreatic T2 mapping values in AP and correlate them with markers of disease severity. STUDY TYPE: Prospective single-center study. POPULATION: 76 adults with AP (20-91 years, females/males: 39/37). FIELD STRENGTH/SEQUENCE: Fat suppressed multiecho spin-echo prototype sequence to quantify T2 signal at 3T MRI. ASSESSMENT: The severity of AP was assessed clinically, biologically, and by contrast-enhanced CT (CECT) performed 48-72 hours after symptom onset. MRI was then performed ≤24 hours after CT. Two readers blinded to any clinical information independently evaluated the T2 values by placing three regions of interest inside the pancreatic head, body, and tail on the T2 mapping MR sequence. Results were compared with corresponding CECT images as the standard and clinical severity parameters, using the length of hospital stay as our primary endpoint. STATISTICAL TESTS: Continuous variables were compared using the Spearman's rank correlation coefficient, analysis of variance (ANOVA) or Student's t-test. RESULTS: T2 values significantly correlated with the length of hospital stay (rs (74) = 0.29), CT severity index (CTSI) (rs (73) = 0.61; CTSI 0-3: 72 ± 14 msec, CTSI 4-10: 88 ± 15), intensive care unit (ICU) admission (t(2.77) = -3.41) and presence of organ failure (t(6.72) = -3.42), whereas the CTSI and Ranson score were not significantly related with ICU admission (CTSI: P = 0.24; Ranson score: P = 0.24) and organ failure (CTSI: P = 0.11; Ranson score P = 0.11). CONCLUSION: T2 mapping correlates with AP severity parameters and is useful for assessing the severity of AP with higher sensitivity than the usual clinical and radiological scoring systems. LEVEL OF EVIDENCE: 1 TECHNICAL EFFICACY: Stage 2.

Combined portal and hepatic vein embolisation in perihilar cholangiocarcinoma.

BACKGROUND: Major hepatectomy in perihilar cholangiocarcinoma (pCCA) patients with a small future liver remnant (FLR) risks posthepatectomy liver failure (PHLF). This study examines combined portal and hepatic vein embolisation (PVE/HVE) to increase preoperative FLR volume and potentially decrease PHLF rates. METHODS: In this retrospective, multicentre, observational study, data was collected from centres affiliated with the DRAGON Trials Collaborative and the EuroLVD registry. The study included pCCA patients who underwent PVE/HVE between July 2016 and January 2023. RESULTS: Following PVE/HVE, 28% of patients (9/32) experienced complications, with 22% (7/32) necessitating biliary interventions for cholangitis. The median degree of hypertrophy after a median of 16 days was 16% with a kinetic growth rate of 6.8% per week. 69% of patients (22/32) ultimately underwent surgical resection. Cholangitis after PVE/HVE was associated with unresectability. After resection, 55% of patients (12/22) experienced complications, of which 23% (5/22) were Clavien-Dindo grade III or higher. The 90-day mortality after resection was 0%. CONCLUSION: PVE/HVE quickly enhances the kinetic growth rate in pCCA patients. Cholangitis impairs chances on resection significantly. Resection after PVE/HVE is associated with low levels of 90-day mortality. The study highlights the potential of PVE/HVE in improving safety and outcomes in pCCA undergoing resection.

Direct comparison and reproducibility of two segmentation methods for multicompartment dosimetry: round robin study on radioembolization treatment planning in hepatocellular carcinoma.

PURPOSE: Investigate reproducibility of two segmentation methods for multicompartment dosimetry, including normal tissue absorbed dose (NTAD) and tumour absorbed dose (TAD), in hepatocellular carcinoma patients treated with yttrium-90 (90Y) glass microspheres. METHODS: TARGET was a retrospective investigation in 209 patients with < 10 tumours per lobe and at least one tumour ≥ 3 cm ± portal vein thrombosis. Dosimetry was compared using two distinct segmentation methods: anatomic (CT/MRI-based) and count threshold-based on pre-procedural 99mTc-MAA SPECT. In a round robin substudy in 20 patients with ≤ 5 unilobar tumours, the inter-observer reproducibility of eight reviewers was evaluated by computing reproducibility coefficient (RDC) of volume and absorbed dose for whole liver, whole liver normal tissue, perfused normal tissue, perfused liver, total perfused tumour, and target lesion. Intra-observer reproducibility was based on second assessments in 10 patients ≥ 2 weeks later. RESULTS: 99mTc-MAA segmentation calculated higher absorbed doses compared to anatomic segmentation (n = 209), 43.9% higher for TAD (95% limits of agreement [LoA]: - 49.0%, 306.2%) and 21.3% for NTAD (95% LoA: - 67.6%, 354.0%). For the round robin substudy (n = 20), inter-observer reproducibility was better for anatomic (RDC range: 1.17 to 3.53) than 99mTc-MAA SPECT segmentation (1.29 to 7.00) and similar between anatomic imaging modalities (CT: 1.09 to 3.56; MRI: 1.24 to 3.50). Inter-observer reproducibility was better for larger volumes. Perfused normal tissue volume RDC was 1.95 by anatomic and 3.19 by 99mTc-MAA SPECT, with corresponding absorbed dose RDC 1.46 and 1.75. Total perfused tumour volume RDC was higher, 2.92 for anatomic and 7.0 by 99mTc-MAA SPECT with corresponding absorbed dose RDC of 1.84 and 2.78. Intra-observer variability was lower for perfused NTAD (range: 14.3 to 19.7 Gy) than total perfused TAD (range: 42.8 to 121.4 Gy). CONCLUSION: Anatomic segmentation-based dosimetry, versus 99mTc-MAA segmentation, results in lower absorbed doses with superior reproducibility. Higher volume compartments, such as normal tissue versus tumour, exhibit improved reproducibility. TRIAL REGISTRATION: NCT03295006.

Defining textbook outcome for selective internal radiation therapy of hepatocellular carcinoma: an international expert study.

BACKGROUND: A textbook outcome (TO) is a composite indicator covering the entire intervention process in order to reflect the "ideal" intervention and be a surrogate for patient important outcomes. Selective internal radiation therapy (SIRT) is a complex multidisciplinary and multistep intervention facing the challenge of standardization. This expert opinion-based study aimed to define a TO for SIRT of hepatocellular carcinoma. METHODS: This study involved two steps: (1) the steering committee (4 interventional radiologists) first developed an extensive list of possible relevant items reflecting an optimal SIRT intervention based on a literature review and (2) then conducted an international and multidisciplinary survey which resulted in the final TO. This survey was online, from February to July 2021, and consisted three consecutive rounds with predefined settings. Experts were identified by contacting senior authors of randomized trials, large observational studies, or studies on quality improvement in SIRT. This study was strictly academic. RESULTS: A total of 50 items were included in the first round of the survey. A total of 29/40 experts (73%) responded, including 23 interventional radiologists (79%), three nuclear medicine physicians (10%), two hepatologists, and one oncologist, from 11 countries spanning three continents. The final TO consisted 11 parameters across six domains ("pre-intervention workup," "tumor targeting and dosimetry," "intervention," "post-90Y imaging," "length of hospital stay," and "complications"). Of these, all but one were applied in the institutions of > 80% of experts. CONCLUSIONS: This multidimensional indicator is a comprehensive standardization tool, suitable for routine care, clinical round, and research.

MDCT-findings in patients with non-occlusive mesenteric ischemia (NOMI): influence of vasoconstrictor agents.

OBJECTIVES: To evaluate the influence of vasoconstrictor agents (VCAs) on signs of vasoconstriction and bowel ischemia on MDCT detected in patients with non-occlusive mesenteric ischemia (NOMI). METHODS: This 8-year single-center retrospective study consecutively included all patients with histopathologically proven NOMI who underwent MDCT ≤ 48 h prior to surgical bowel resection. Two blinded radiologists jointly reviewed each examination for signs of bowel ischemia, abdominal organ infarct, mesenteric vessel size and regularity, and ancillary vascular findings. VCA administration (length and dosage), clinical and biochemical data, risk factors, and outcomes were retrieved from patients' medical records. Subgroup comparisons were performed. RESULTS: Ninety patients were included (59 males, mean age 65 years); 40 (44.4%) had received VCAs before MDCT. Overall mortality was 32% (n = 29), with no significant difference between the two groups. In patients treated with VCAs, the calibre of the superior mesenteric artery (SMA) was smaller (p = 0.032), and vasoconstriction of its branches tended to be more important (p = 0.096) than in patients not treated with VCAs. The presence and extent of bowel ischemia did not significantly correlate with VCA administration, but abdominal organ infarcts tended to be more frequent (p = 0.005) and involved more organs (p = 0.088). The VCA group had lower mean arterial pressure (p = 0.006) and lower hemoglobin levels (p < 0.001). Several biomarkers of organ failure and inflammation, differed significantly with VCA use, proving worse clinical condition. CONCLUSIONS: MDCT demonstrates more severe SMA vasoconstriction and tends to show increased abdominal organ infarcts after VCA administration in NOMI patients compared to NOMI patients not treated with VCAs. KEY POINTS: • In critically ill patients with NOMI, MDCT demonstrates VCA support via increased vasoconstriction of the main SMA and its branches. • VCA administration in NOMI patients tends to contribute to the development of organ infarcts, as shown on MDCT. • An important degree of vasoconstriction in NOMI patients may indicate insufficient resuscitation and, thus, help clinicians in further patient management.

Tc-99m mebrofenin hepatobiliary scintigraphy to assess future liver remnant function before major liver surgery.

BACKGROUND AND OBJECTIVES: Assessment of liver function is paramount before hepatectomy. This study aimed to assess future liver remnant function (FLR-F) using hepatobiliary scintigraphy (HBS) and to compare it to FLR volume (FLR-V) in the prediction of posthepatectomy liver failure (PHLF). The impact of volume and function gains were also assessed in patients undergoing portal vein embolization (PVE) or liver venous deprivation (LVD). METHODS: All consecutive patients undergoing major hepatectomy between 02/2018 and 09/2021 with preoperative HBS were included. FLR-V was expressed as percentage of total liver volume and analyzed using preoperative computed tomography. FLR-V and FLR-F gains after embolization were expressed in percentage. Receiver operating characteristic analysis was performed to compare both methods in predicting PHLF. RESULTS: Thirty-six patients were included. PVE and LVD were performed in 4 (11%) and 28 patients (78%), respectively. Overall, PHLF occurred in eight patients (22%). FLR-F gain after embolization showed significant ability to predict PHLF (area under the curve [AUC] = 0.789), with cut-off value of 150% showing a sensitivity of 1.00, a specificity of 0.42, and a negative predictive value of 1.00. CONCLUSION: Preoperative HBS shows a high sensitivity to predict PHLF when HBS is performed twice to measure the function gain after venous embolization.

Polyethylene Glycol Drug-Eluting Embolic Microspheres Loaded with Doxorubicin for the Treatment of Hepatocellular Carcinoma: Feasibility, Safety, and Pharmacokinetic Study.

PURPOSE: Polyethylene glycol drug-eluting microspheres (PEG-DEMs) can be loaded to elute doxorubicin. The current study evaluated the pharmacokinetic profile and safety of PEG-DEMs in the treatment of patients with hepatocellular carcinoma (HCC). MATERIALS AND METHODS: The current prospective, multicenter, dose-escalation study enrolled 25 patients (68% men) with early or intermediate stage HCC and a performance status of 0. Patients in Cohort I were assigned to receive target doxorubicin doses of 75, 100, or 150 mg. Analyses were performed on the basis of the specific dose of doxorubicin that the patients received because some patients received less than the assigned dose. Patients in Cohort II received the maximum safe tested dose. Adverse events were classified according to the Common Terminology Criteria for Adverse Events version 4.03. The tumor response was evaluated every 3 months according to the European Association for the Study of the Liver criteria and modified Response Evaluation Criteria in Solid Tumors. RESULTS: The maximum tested safe dose of doxorubicin was 150 mg. For the groups that received ≤75, 75-100, and 101-150 mg of doxorubicin, the peak plasma concentrations were 286.7 ng/mL ± 220.1, 157.1 ng/mL ± 94.6, and 245.4 ng/mL ± 142.8, respectively; the areas under the curves calculated from 0 to 24 h were 421.7 (ng × h)/mL ± 221.2, 288.1 (ng × h)/mL ± 100.9, and 608.3 (ng × h)/mL ± 319.3, respectively, with almost complete clearance at 24 h. There was no death within 30 d. The best objective response rate was 81%, and the disease control rate was 91%. The median overall survival was 27.2 months (95% confidence interval [CI], 17.5 months to not evaluated [n.e.]); the median progression-free survival was 9.8 months (95% CI, 5.5 months to n.e.). CONCLUSIONS: PEG-DEMs demonstrated a favorable safety profile with low systemic concentration of doxorubicin, and promising efficacy.

Consensus Guidelines for the Definition of Time-to-Event End Points in Image-guided Tumor Ablation: Results of the SIO and DATECAN Initiative.

There is currently no consensus regarding preferred clinical outcome measures following image-guided tumor ablation or clear definitions of oncologic end points. This consensus document proposes standardized definitions for a broad range of oncologic outcome measures with recommendations on how to uniformly document, analyze, and report outcomes. The initiative was coordinated by the Society of Interventional Oncology in collaboration with the Definition for the Assessment of Time-to-Event End Points in Cancer Trials, or DATECAN, group. According to predefined criteria, based on experience with clinical trials, an international panel of 62 experts convened. Recommendations were developed using the validated three-step modified Delphi consensus method. Consensus was reached on when to assess outcomes per patient, per session, or per tumor; on starting and ending time and survival time definitions; and on time-to-event end points. Although no consensus was reached on the preferred classification system to report complications, quality of life, and health economics issues, the panel did agree on using the most recent version of a validated patient-reported outcome questionnaire. This article provides a framework of key opinion leader recommendations with the intent to facilitate a clear interpretation of results and standardize worldwide communication. Widespread adoption will improve reproducibility, allow for accurate comparisons, and avoid misinterpretations in the field of interventional oncology research. Published under a CC BY 4.0 license. Online supplemental material is available for this article. See also the editorial by Liddell in this issue.

[Preoperative liver venous deprivation]. / Embolisation portale et sus-hépatique combinée avant hépatectomie ma.

Some hepato-biliary cancers require major liver resections. Post hepatectomy liver failure is a complication that occurs when the remnant liver cannot maintain its synthetic and excretory functions. To overcome this issue, portal vein embolization has been developed to induce future remnant liver hypertrophy preoperatively. However, up to 20% of patients cannot proceed to the hepatectomy due to insufficient hypertrophy or tumor progression in the interval between the embolization and the planned surgery. Liver venous deprivation (LVD) is a technique that combine ipsilateral portal and hepatic vein embolization. With this technique, the hypertrophy seems to be faster and more important, with low complications rate and no mortality associated with the procedure.

Certains cancers hépatobiliaires nécessitent des résections hépatiques majeures. L'insuffisance hépatocellulaire est une complication postopératoire avec un risque de mortalité qui survient lorsque le foie restant ne peut maintenir ses fonctions de synthèse et d'excrétion. L'embolisation de la veine porte a été développée pour induire une hypertrophie du futur foie restant en préopératoire afin d'éviter cette complication. Cependant, 20 % des patients ne peuvent pas bénéficier de l'hépatectomie en raison d'une hypertrophie insuffisante ou d'une progression de la maladie oncologique dans l'intervalle entre l'embolisation et la chirurgie. L'embolisation portale et sus-hépatique combinée est une technique qui consiste à combiner durant le même geste l'embolisation de la veine porte et de la veine sus-hépatique ipsilatérale. Par cette technique, l'hypertrophie semble alors plus rapide et importante, avec peu de complications et aucune mortalité en lien avec la procédure.

[Early TIPS: a practical review after 15 years of scientific evidence]. / Early TIPS†: une revue pratique après 15 ans d'évidence scientifique.

Gastrointestinal bleeding related to portal hypertension of cirrhosis is associated with a significant mortality risk (10-20 %). The transjugular intrahepatic portosystemic shunt (TIPS) reduces the hepatic venous pressure gradient. Several studies have evaluated early TIPS insertion (within 72h from diagnostic endoscopy) with the aim of improving outcomes in selected patients at high risk of failure to control bleeding and/or rebleeding. The majority reported an improvement of 6-week and 1-year survival rates and a decrease in failure to control bleeding and rebleeding. Here, we review the available data and discuss the limits of early TIPS in terms of patient identification and access to the procedure.

Les patients hospitalisés pour hémorragie digestive sur hypertension portale ont un risque élevé de mortalité (10-20%). La création d'un shunt portosystémique par voie transjugulaire (TIPS) permet de diminuer le gradient de pression entre le système porte et la circulation systémique (gradient portosystémique) réduisant ainsi le risque hémorragique. Chez des patients sélectionnés à haut risque de non-contrôle et/ou de récidive hémorragique, plusieurs études ont évalué l'intérêt de l'insertion précoce d'un TIPS (early TIPS) dans les 72 heures suivant l'endoscopie diagnostique. Elles observent en majorité une amélioration de la survie à 6 semaines et 1 an et une diminution du non-contrôle ou de la récidive hémorragique. Nous proposons ici une revue des études disponibles et discutons des limites de cette stratégie en termes d'accessibilité à la technique et d'identification des patients nécessitant encore régulièrement une discussion collégiale au cas par cas.

Vandetanib-eluting Radiopaque Beads: Pharmacokinetics, Safety, and Efficacy in a Rabbit Model of Liver Cancer.

Background Transarterial chemoembolization with cytotoxic drugs is standard treatment for unresectable intermediate-stage hepatocellular carcinoma but achieves suboptimal outcomes because of hypoxic stress and the production of detrimental proangiogenic factors. An alternative approach using radiopaque embolization beads loaded with the antiangiogenic drug vandetanib may provide improved anticancer efficacy. Purpose To evaluate the pharmacokinetics, safety, and efficacy of vandetanib-eluting radiopaque bead (VERB) chemoembolization of rabbit liver tumors. Materials and Methods Between April 2015 and March 2016, 60 New Zealand white rabbits with VX2 liver tumors were randomly treated with VERBs at different doses, with nonloaded radiopaque beads (ROBs), or with intra-arterial vandetanib suspension (VS) or were not treated. Vandetanib plasma concentration and tumor growth at US were evaluated. Animals were euthanized after 3 days or 3 weeks. Assessment included bead distribution at x-ray imaging and histologic examination, tumor viability at histologic examination, and vandetanib tissue concentration. Group comparison analysis (Mann-Whitney, Kruskal-Wallis, and χ2 tests) and predictive factor analysis for tumor growth and viability were performed. Results Vandetanib plasma concentration was lower with VERBs than with VS (P < .01), while concentration in tumor was higher for VERBs (than for VS) at 3 days (median, 29.2 vs 2.74 ng/mg; P = .48). Tumor growth was lower with VERBs than with ROBs and with VS at both time points, with median values of +114%, +192%, and +466% at 3 weeks, respectively. Tumor viability was lower at 3 days for VERBs than for ROBs and for VS (3%, 18%, and 38%, respectively) but was not significantly different at 3 weeks. The volume of bead in tumor was a significant predictive factor for lower tumor growth in multivariable analysis at 3 days (P = .03). Drug tumor concentration was a significant predictive factor for lower tumor growth at 3 weeks (P = .04). Conclusion Vandetanib-eluting radiopaque bead chemoembolization showed a pharmacokinetic advantage over intra-arterial drug administration in a preclinical model of liver cancer. High deposition of beads and high vandetanib concentration in tumor led to stronger antitumor effects. © RSNA, 2019 Online supplemental material is available for this article. See also the editorial by Kim and Van den Abbeele in this issue.

Electromagnetic navigation system combined with High-Frequency-Jet-Ventilation for CT-guided hepatic ablation of small US-Undetectable and difficult to access lesions.

Objectives: To report the feasibility and efficacy of percutaneous ablation of small hepatic malignant tumors that are invisible on ultrasound and inaccessible using in-plane CT guidance, using a combination of high-frequency jet-ventilation (HFJV) and electromagnetic (EM) needle tracking. Methods: This study reviewed 27 percutaneous ablations of small hepatic tumors (<2 cm) performed using EM navigation-based probe placement and HFJV. All lesions were invisible on ultrasound and difficult to reach on CT requiring a double-oblique approach. The primary outcome was technical efficacy, defined as complete lesion coverage, and evaluated on contrast enhanced MRI after 3 and 6 months. Needle placement accuracy, the number of control CT acquisitions, procedure time, complications and radiation doses were assessed. Results: Twenty-one patients with 27 treated lesions (14 hepatocellular carcinomas and 13 metastases) were included in this study. Mean tumor size was 12 ± 5.7 mm. Thirty-three percent of the lesions were located on the hepatic dome. Complete ablation was obtained in 100% at the 3- and 6-month MRI follow-up. The ablation probe was correctly placed on the first pass in 96%, with a mean path-to-tumor angle of 7 ± 4 degrees and a mean tip-to-tumor distance of 22 ± 19mm. A readjustment for additional overlapping application resulted in complete treatment in 4 patients. Needle placement took a mean 23 ± 12 min with mean radiation doses of 558 mGy*cm. No major complications were reported. Conclusion: Percutaneous liver ablation of lesions that cannot be seen on US and requiring out-of-plane CT access can be successfully and safely treated using electromagnetic-based navigation and jet-ventilation.

[Radiofrequency ablation of thyroid nodules†: an alternative to surgery or first-line treatment†?] / Ablation des nodules thyroïdiens par radiofréquence†: alternative à la chirurgie ou traitement de première ligne†?

Thyroid nodules are a very common problem whose prevalence increases with age. When treatment is considered, surgical excision is traditionally the first choice, except in the case of hyperfunctioning nodules, where treatment with radioactive iodine plays a major role. In recent years, there has been increasing experience in the thermal ablation of thyroid nodules by radiofrequency, with very encouraging results. This article aims to discuss the role of radiofrequency thermal ablation in the management of benign thyroid nodules by reviewing the indications, adverse effects and limitations of this method.

Les nodules thyroïdiens sont un problème très fréquent dont la prévalence augmente avec l'âge. Lorsqu'un traitement est envisagé, l'excision chirurgicale occupe jusqu'à présent la première place, sauf dans le cas des nodules hyperfonctionnels où la radiothérapie métabolique par iode 131 joue un rôle principal. Depuis quelques années, il existe une expérience croissante dans la thermoablation des nodules thyroïdiens par radiofréquence, avec des résultats très encourageants. Cet article a pour but de discuter la place de la thermoablation par radiofréquence dans la prise en charge des nodules thyroïdiens bénins en passant en revue les indications, les effets indésirables et les limitations de cette méthode.

[Outpatient follow-up of liver transplant recipients: the essential role of the general practitioner]. / Suivi ambulatoire du patient transplanté hépatique: le rôle essentiel du médecin généraliste.

The population of liver transplant recipients has increased in Switzerland over the last few years. Morbidity and mortality after liver transplantation are due, in the early post-transplant period, to surgical and infectious complications as well as to rejection, whereas cardiovascular, metabolic, renal and oncologic complications are the most frequent complications in the late post-transplant period. The role of the general practitioner in the long-term follow-up of liver transplant recipients is of the highest importance and can represent the first-line care of these patients as soon as 6 to 12 months post-transplantation, while maintaining a close and regular collaboration with the transplant center. Multidisciplinary and structured follow-up, along with some specific screening tests, is warranted in order to refine patient management in a timely manner and to optimize outcomes.

Les patients greffés hépatiques représentent une population croissante en Suisse. La morbidité et la mortalité après cette procédure sont liées, dans la phase précoce, aux complications chirurgicales et infectieuses ainsi que, dans une moindre mesure, au rejet, puis surviennent dans la phase tardive les complications cardiovasculaires, métaboliques, rénales et oncologiques, liées en grande partie aux traitements immunosuppresseurs. Le rôle du médecin généraliste dans le suivi médical du patient greffé hépatique est essentiel et peut être de premier recours dès 6 à 12 mois après la transplantation, tout en gardant une collaboration étroite et régulière avec le centre de transplantation. Un suivi multidisciplinaire, régulier et structuré, associé à certaines mesures de dépistage, est indispensable, afin d'adapter précocement la prise en charge et ainsi d'optimaliser le devenir des patients après la greffe.

Pre-treatment magnetic resonance-based texture features as potential imaging biomarkers for predicting event free survival in anal cancer treated by chemoradiotherapy.

AIM: To assess regular MRI findings and tumour texture features on pre-CRT imaging as potential predictive factors of event-free survival (disease progression or death) after chemoradiotherapy (CRT) for anal squamous cell carcinoma (ASCC) without metastasis. MATERIALS AND METHODS: We retrospectively included 28 patients treated by CRT for pathologically proven ASCC with a pre-CRT MRI. Texture analysis was carried out with axial T2W images by delineating a 3D region of interest around the entire tumour volume. First-order analysis by quantification of the histogram was carried out. Second-order statistical texture features were derived from the calculation of the grey-level co-occurrence matrix using a distance of 1 (d1), 2 (d2) and 5 (d5) pixels. Prognostic factors were assessed by Cox regression and performance of the model by the Harrell C-index. RESULTS: Eight tumour progressions led to six tumour-specific deaths. After adjusting for age, gender and tumour grade, skewness (HR = 0.131, 95% CI = 0-0.447, p = 0.005) and cluster shade_d1 (HR = 0.601, 95% CI = 0-0.861, p = 0.027) were associated with event occurrence. The corresponding Harrell C-indices were 0.846, 95% CI = 0.697-0.993, and 0.851, 95% CI = 0.708-0.994. CONCLUSION: ASCC MR texture analysis provides prognostic factors of event occurrence and requires additional studies to assess its potential in an "individual dose" strategy for ASCC chemoradiation therapy. KEY POINTS: • MR texture features help to identify tumours with high progression risk. • Texture feature maps help to identify intra-tumoral heterogeneity. • Texture features are a better prognostic factor than regular MR findings.

Hepatocellular carcinoma abutting large vessels: comparison of four percutaneous ablation systems.

PURPOSE: To compare overall local tumour progression (OLTP), defined as the failure of primary ablation or local tumour progression, with single applicator monopolar radiofrequency ablation (RFA), microwave ablation (MWA), cluster-RFA and multi-bipolar radiofrequency (mbpRFA) in the treatment of hepatocellular carcinoma (HCC) ≤ 5 cm abutting large vessels (≥3 mm). MATERIALS AND METHODS: This multicenter, retrospective, per-nodule study was performed from 2007 to 2015. The study was approved by the ethics review board, and informed consent was waived. A total of 160/914 HCC nodules treated by thermal ablation and abutting large vessels (40 per treatment group) treated by monopolar RFA, MWA, cluster-RFA or mbpRFA were matched for tumour size, alpha-feto-protein level and vessel size. OLTP rates were compared by the log-rank test and the multivariate Cox model after matching. RESULTS: No differences were observed in tumour size, vessel size or alpha-feto-protein levels among the three groups (p = 1). The cumulative 4-year OLTP rates following monopolar RFA, cluster-RFA, multi-bipolar RFA and MWA were 50.5%, 16.3%, 16.3% and 44.2%, respectively (p = 0.036). On multivariate Cox regression, vessel size ≥10 mm, monopolar RFA and MWA were independent risk factors of OLTP compared to cluster-RFA or mbpRFA. CONCLUSION: Multi-applicator RFA provides better local tumour control in HCC abutting large vessels than single-applicator techniques (monopolar RFA or MWA).

Local recurrence rate in patients with colorectal cancer liver metastasis after wedge resection or percutaneous radiofrequency ablation.

PURPOSE: To compare local recurrence (LR) rate in patients with colorectal cancer liver metastasis (CRCLM) after surgical wedge resection (WR) or radiofrequency ablation (RFA) and to investigate predictive factors of LR. MATERIALS AND METHODS: This single-centre, retrospective, institutional review board-approved study including 43 consecutive patients with 121 metastases treated by WR and 60 patients with 110 metastases treated by RFA between 2007 and 2014 with 23 and 18.5 months of follow-up, respectively. Demographics and tumour characteristics were compared using the unpaired t-test and chi-square test. Predictive factors for LR (lesion size, depth, relation to hepatic vessels, intervention, margin status) were investigated in uni- and multivariate analyses. RESULTS: Patient and CRCLM characteristics were similar in both groups. Mean lesion size and depth in the WR and RFA groups were 18 mm and 15 mm (p = 0.03), and 19 mm and 26 mm (p < 0.001), respectively. LR showed a trend towards difference in favour of RFA (19% and 10% in the WR and RFA groups, respectively, p = 0.06). Positive margins and lesion depth were predictive factors of LR in the WR group (p = 0.03 and p = 0.02, respectively, on uni- and multivariable analyses). Lesion depth and proximity to a vein increased the risk of positive margins on pathology after WR (p = 0.04 and p < 0.001, respectively). Our analysis did not identify any predictive factors of LR following RFA. CONCLUSION: Our study showed a trend towards a lower LR rate with RFA compared to WR. Lesions located deep in the liver and/or close to large vessels are at high risk of LR following WR, while curative treatment can be obtained with RFA.