Tommaso Vincenzo Bartolotta

60KDa chaperonin (HSP60) is over-expressed during colorectal carcinogenesis.

The aim of the present study was to evaluate the expression of the heat shock protein 60 (HSP60), a mitochondrial matrix-associated protein belonging to the chaperonin family, in colorectal adenomas and cancers, comparing them to normal colonic tissues and hyperplastic polyps. We performed both immunohistochemistry and Western blot analysis for HSP60. Immunohistochemistry resulted positive in all tubular adenomas and infiltrating adenocarcinomas. By contrast, normal tissues and hyperplastic polyps were negative. Quantitative analysis showed that tubular adenomas with different levels of dysplasia did not present statistical differences concerning HSP60 positivity. In addition, carcinomas always showed the highest expression. Western blot analysis confirmed these observations. These data suggest that HSP60 over-expression is an early event in carcinogenesis. We suspect that HSP60 plays a different role in colorectal carcinogenesis with respect to that in normal cells, which foresees its possible use as diagnostic and prognostic tools.

FOCAL LIVER LESIONS: CONTRAST-ENHANCED ULTRASOUND

Contrast-enhanced ultrasound (CEUS) represents a significant breakthrough in sonography and it is being increasingly used for the evaluation of focal liver lesions (FLLs). The unique feature of CEUS of non-invasively assessing in real-time liver perfusion throughout the vascular phase has led to a dramatic improvement in diagnostic accuracy of US in either detection or characterization of FLLs, as well as in the guidance and evaluation of response of therapeutic procedures. Currently, CEUS is included as a part of the suggested diagnostic work-up of FLLs, resulting in a better patient management and cost-effective therapy delivering. After a brief description of the basis of different CEUS techniques, contrast-enhancement patterns of different types of benign and malignant FLLs, among hepatic pseudolesions, will be described and discussed on the basis of our experience and literature data. At the same time, the most recent concepts and the use of CEUS in different clinical settings will be presented.

Hepatocellular cancer response to radiofrequency tumor ablation: contrast-enhanced ultrasound

Radiofrequency ablation (RFA) is increasingly being used as percutaneous treatment of choice for patients with early stage hepatocellular carcinoma (HCC). An accurate assessment of the RFA therapeutic response is of crucial importance, considering that a complete tumor ablation significantly increases patient survival, whereas residual unablated tumor calls for additional treatment. Imaging modalities play a pivotal role in accomplishing this task, but ultrasound (US) is not considered a reliable modality for the evaluation of the real extent of necrosis, even when color/power Doppler techniques are used. Recently, newer microbubble-based US contrast agents used in combination with grey-scale US techniques, which are very sensitive to non-linear behavior of microbubbles, have been introduced. These features have opened new prospects in liver ultrasound and may have a great impact on daily practice, including cost-effective assessment of therapeutic response of percutaneous ablative therapies. Technical evolution of CEUS focusing on findings after RFA are illustrated. These latter are detailed, cross-referenced with the literature and discussed on the basis of our personal experience. Timing of CEUS posttreatment assessment among with advantages and limitations of CEUS are also described with a perspective on further technologic refinement.

Characterization of hypoechoic focal hepatic lesions in patients with fatty liver: diagnostic performance and confidence of contrast-enhanced ultrasound

The objective of this study was to assess the diagnostic performance of contrast-enhanced ultrasound (CEUS) to characterize hypoechoic focal hepatic lesions (HFHL) in fatty liver (FL). A study group of 105 patients with FL and 105 HFHLs (52 malignant and 53 benign) underwent CEUS after SonoVue administration. Two blinded readers independently reviewed baseline ultrasound (US) and CEUS scans and classified each lesion as malignant or benign on a five-point scale of confidence, and recorded whether further imaging work-up was needed. Sensitivity, specificity, areas under the receiver operating characteristic (ROC) curve (Az), and interobserver agreement were calculated. We observed that the diagnostic confidence improved after reviewing CEUS scans for both readers (Az=0.706 and 0.999 and Az=0.665 and 0.990 at baseline US and CEUS, respectively; p<0.0001). Inter-reader agreement increased (weighted k=0.748 at baseline US vs. 0.882 at CEUS). For both readers, after CEUS, the occurrence of correctly characterized lesions increased (from 27/105 [27.5%] to 94/105 [89.5%], and from 19/105 [18.1%] to 93/105 [88.6%], respectively; p<0.0001) and the need for further imaging decreased (from 93/105 [88.6%] to 26/105 [24.8%], and from 96/105 [91.4%] to 40/105 [38.1%], respectively; p<0.0001). We conclude that CEUS improves the diagnostic performance of radiologists in the characterization of HFHLs in FL and reduces the need for further imaging work-up.

Benign focal liver lesions: spectrum of findings on SonoVue-enhanced pulse-inversion ultrasonography

The prevalence of benign focal liver lesions (BFLL) is high both in the general population and in patients with known malignancies. The gray-scale ultrasound (US) technique is usually the first-line imaging modality used in the radiological workup of such lesions, but unfortunately it lacks specificity. Furthermore, Doppler examination may often be unsatisfactory owing to motion artefacts, or when small or deeply located lesions are evaluated. Recently, microbubble-based contrast agents used in combination with gray-scale US techniques, which are very sensitive to nonlinear behavior of microbubbles, have led to a better depiction of both microvasculature and macrovasculature of focal hepatic masses, thus improving the reliability of using US in the assessment of liver tumors. This review illustrates the spectrum of enhancement patterns of BFLL on contrast-enhanced ultrasonography with SonoVue, a second-generation microbubble-based contrast agent.

Incidentally discovered thyroid nodules: incidence, and greyscale and colour Doppler pattern in an adult population screened by real-time compound spatial sonography

Purpose.Our aim was to assess the incidence and ultrasound features of thyroid nodules in an adult population screened by means of high-resolution ultrasonography (HRUS) and to evaluate the contribution of real-time spatial compound sonography (CS) in terms of image quality.Materials and methods.A total of 704 consecutive patients (400 women, 304 men) without thyroid disease underwent HRUS and CS examination of the thyroid gland. Number, size, location, echotexture and colour Doppler pattern of detected nodules were assessed. Two radiologists also assessed image quality of the two techniques.Results.Seven hundred and eleven thyroid nodules (size range 0.18–4.1 cm; mean: 1.1 cm) were detected in 233 subjects (33.1%). Of these, 416 (58.5%) were found in 143 women whereas 295 (41.5%) were detected in 90 men. In both genders, the number of detected nodules increased with age, with the highest prevalence in the seventh decade (p<0.001). There were 461/711 (64.9%) thyroid nodules that were hypoechoic, and 449/711 (63.1%) had peripheral vascularity only (p<0.001). Fineneedle aspiration (FNA) revealed no malignancies. CS was graded better than HRUS in 621/711 (87.3%) cases (p<0.001).Conclusions.The prevalence of benign, small, hypoechoic thyroid nodules with peripheral vascularity was high in our series, thus suggesting a conservative approach. CS provided better image quality compared with HRUS.

Analysis of different contrast enhancement patterns after microbubble-based contrast agent injection in liver hemangiomas with atypical appearance on baseline scan.

BackgroundWe describe different possible enhancement patterns in liver hemangiomas with atypical appearance on baseline ultrasound after microbubble-based contrast agent injection.MethodsFrom a series of 253 consecutive lesions that were indeterminate on baseline ultrasound and then scanned after injection of air-filled microbubble contrast agent, 65 focal liver lesions were retrospectively selected on the basis of a diagnosis of liver hemangioma on multiphase contrast-enhanced computed tomography (n = 23), magnetic resonance imaging (n = 27), or histology (n = 15). Each lesion was scanned during arterial phase (30 s after microbubble injection) and late phase (5 min after injection). On-site sonologists performed retrospective assessment of contrast-enhancement patterns by consensus.ResultsCentripetal fill-in preceded (n = 50) or not preceded (n = 3) by peripheral nodular/rim-like enhancement was the prevalently observed contrast-enhancement pattern, equivalent to the typical enhancement pattern of liver hemangiomas on contrast-enhanced computed tomography or magnetic resonance imaging. In the remaining lesions, additional enhancement patterns (diffuse contrast enhancement with rapid fill-in and a late hyper-isoechoic appearance, n = 6; peripheral nodular enhancement with a late hypoechoic appearance, n = 3; or persistent heterogeneous and hyperechoic appearance, n = 3) were observed.ConclusionDifferent contrast-enhancement patterns are possible in atypical liver hemangiomas after microbubble injection. Typical centripetal fill-in is the prevalent pattern and its evidence allows diagnosis.

Noninvasive evaluation of the celiac trunk and superior mesenteric artery with multislice CT in patients with chronic mesenteric ischaemia

PurposeThis study sought to assess the role of multislice computed tomography (MSCT) in patients with suspected chronic mesenteric ischaemia (CMI).Materials and methodsForty-five patients (29 men; mean age 68) underwent MSCT angiography of the abdomen for suspected CMI (main clinical finding: postprandial abdominal pain). The scan protocol was detectors/collimation 16/0.75 mm; feed 36 mm/s; rotation time 500 ms; increment 0.4 mm; 120–150 mAs and 120 kVp. A volume of 80 ml of contrast material was administered through an antecubital vein (rate 4 ml/s), followed by 40 ml of saline (rate 4 ml/s). Images were analysed on the workstation with different algorithms (axial image scrolling, multiplanar reconstructions, maximum intensity projection, volume rendering). Targeted central lumen-line reconstructions (curved reconstructions) were obtained along the celiac trunk (CeT) and superior mesenteric artery (SMA). Vessel occlusions and significant (>50%) stenosis were recorded.ResultsImage generation and interpretation required 25 min. Stenosis and/or occlusions were detected in 29 (65%) cases on the CeT and in 32 (71%) on the SMA. Of those lesions (n=61), 44 (49%) were classified as not significant. In 16 (35%) cases, there was a simultaneous stenosis and/or occlusion of the CeT and SMA (confirmed by conventional angiography). In six (13%) cases, there were no lesions affecting the CeT, SMA or their branches (confirmed by clinical follow-up).ConclusionsMSCT angiography can play a major role in the detection of stenosis of the abdominal arteries in patients with suspected CMI.RiassuntoObiettivoValutare il ruolo della TC multistrato (MSCT) nei pazienti con sospetta ischemia cronica mesenterica (ICM).Materiali e metodiQuarantacinque pazienti (29 uomini; età media 68) sono stati sottoposti ad angiografia dei vasi addominali mediante MSCT per sospetta ICM (principale sintomo clinico: dolore addominale post-prandiale). Protocollo di scansione: detettori/collimazione 16/0,75 mm; avanzamento 36 mm/s; tempo di rotazione 500 ms; incremento 0,4 mm; mAs 120–150 e kVp 120. Ottanta millilitri di mezzo di contrasto sono stati somministrati per via antecubitale (velocità: 4 ml/s), seguiti da 40 ml di soluzione salina (velocità: 4 ml/s). Le immagini sono state analizzate mediante workstation con diversi algoritmi (cinescrolling delle immagini assiali, MPR-ricostruzioni multiplanari reconstructions, MIP, Maximum Intensity Projections, VR, Volume Rendering). Ricostruzioni multiplanari curvate sono state effettuate lungo il tronco celiaco (TCe) e l’arteria mesenterica superiore (AMS). L’occlusione e la stenosi significativa (>50%) sono state rilevate.RisultatiLa generazione ed interpretazione delle immagini hanno richiesto in media 25 min. Stenosi e/o occlusione sono state rilevate in 29 (65%) casi sul TCe, ed in 32 (71%) casi sull’AMS. Di queste lesioni (n=61), 44 (49%) sono previstate classificate come non significative. In 16 (35%) casi è stata osservata una stenosi e/o occlusione simultanea di TCe e AMS (confermate con angiografia convenzionale). In 6 (13%) casi non vi era alcuna lesione a carico del TCe, dell’AMS o dei loro rami principali (confermato al follow-up clinico).ConclusioniL’angiografia MSCT può avere un ruolo importante nella rilevazione delle stenosi dei vasi addominali in pazienti con sospetta ICM.

Characterization of benign hepatic tumors arising in fatty liver with SonoVue and pulse inversion US

BackgroundWe describe the spectrum of contrast-enhancement patterns of benign hepatic tumors arising in fatty liver on contrast-enhanced ultrasound (US).MethodsSixteen patients (12 women and four men) with 27 benign hepatic tumors (17 hemangiomas, eight focal nodular hyperplasias, and two hepatocellular adenomas) arising in fatty liver underwent baseline and pulse inversion US after administration of SonoVue. Two experienced radiologists evaluated baseline echogenicity and dynamic enhancement pattern of each lesion in comparison with adjacent liver parenchyma.ResultsAfter administration of SonoVue, in the arterial phase 13 of 17 hemangiomas showed peripheral globular enhancement and one showed a rim of peripheral enhancement, followed by progressive centripetal fill-in, which was complete in 10 of 14 cases and incomplete in four. Three of 18 hemangiomas showed rapid and complete fill-in in the arterial phase. Eight of eight focal nodular hyperplasias became hyperechoic in comparison with adjacent liver parenchyma in the arterial phase and slightly hyperechoic or isoechoic in the portal venous and delayed phases. Both adenomas showed strong arterial contrast enhancement that became less intense in the portal venous and delayed phases.ConclusionContrast-enhanced US after administration of SonoVue enables depiction of typical contrast-enhancement patterns in most benign hepatic tumors arising in fatty liver, thus providing useful clues for characterization.

Characterisation of focal liver lesions undetermined at grey-scale US: contrast-enhanced US versus 64-row MDCT and MRI with liver-specific contrast agent

PurposeThe aim of this study was to assess the role of contrast-enhanced ultrasonography (CEUS) in the characterisation of focal liver lesions in comparison with multidetector computed tomography (MDCT) and magnetic resonance imaging (MRI) with liver-specific contrast agent.Materials and methodsOne hundred and eighty-seven focal liver lesions, 91 malignant and 96 benign (mean size 3.2 cm) — proved by biopsy (n=12), histology (n=4), MDCT (n=108), MRI (n=44) MDCT/MRI (n=19) — in 159 patients were studied by CEUS. Two expert radiologists consensually evaluated the contrast-enhancement patterns at CEUS. For each lesion, they assessed: (a) nature (benign, malignant, not assessable), (b) specific diagnosis and (c) need for further radiological evaluation. Sensitivity, specificity, positive and negative predictive values and diagnostic accuracy of CEUS were calculated.ResultsA total of 167/187 (89.3%) lesions were correctly assessed as benign or malignant at CEUS, whereas 14/187 (7.5%) lesions remained undetermined and 6/187 (3.2%) were incorrectly assessed. Sensitivity, specificity, positive and negative predictive values and diagnostic accuracy of CEUS were, respectively, 89%, 89.6%, 89%, 89.6% and 89.3%. The need for further radiological evaluation decreased to 46/187 (24.6%) lesions after CEUS (p<0.001).ConclusionsIn selected cases, CEUS can be considered an effective alternative to MDCT and MRI and reduce the need for further radiological workup.RiassuntoObiettivoScopo del nostro studio è stato valutare il ruolo dell’ecocontrastografia nella caratterizzazione delle lesioni focali epatiche confrontandola con apparecchiature di tomografia computerizzata multidetettore (TCMD) e risonanza magnetica (RM) con mezzo di contrasto (MdC) epatospecifico.Materiali e metodiCentottantasette lesioni focali epatiche, 91 maligne e 96 benigne (diametro medio: 3,2 cm), in 159 pazienti, confermate mediante biopsia (n=12), istologia (n=4) TCMD, (n=108), RM (n=44) TCMD e RM (n=19), sono state studiate con ecocontrastografia, TCMD e/o RM. Due radiologi hanno valutato in consenso gli aspetti ecocontrastografici, indicando per ciascuna lesione: a) diagnosi di natura (benigna, indeterminata, maligna); b) diagnosi specifica; c) necessità di ulteriori indagini radiologiche. Sono stati calcolati sensibilità, specificità, valori predittivo positivo e negativo, nonché l’accuratezza diagnostica dell’ecocontrastografia.RisultatiL’ecocontrastografia ha consentito una corretta diagnosi (benigne vs maligne) in 167/187 (89,3%) casi. Quattordici/187 (7,5%) lesioni sono rimaste indeterminate e 6/187 (3,2%) non sono state correttamente caratterizzate dopo ecocontrastografia, con valori di sensibilità, specificità, valore predittivo positivo, negativo e accuratezza diagnostica pari, rispettivamente, all’89%, all’89,6%, all’89%, all’89,6% e all’89,3%. Dopo ecocontrastografia, la necessità di ricorrere a ulteriori indagini radiologiche si è ridotta a 46/187 casi (24,6%) (p<0,001).ConclusioniL’ecocontrastografia può essere considerata, in casi selezionati, una valida alternativa alla TCMD ed alla RM, riducendo il ricorso ad ulteriori indagini radiologiche.