Using contrast-enhanced sonography to assess the effectiveness of transcatheter arterial embolization for hepatocellular carcinoma

Utility of Contrast-Enhanced Ultrasound for Early Therapeutic Evaluation of Hepatocellular Carcinoma After Transcatheter Arterial Chemoembolization

OBJECTIVES

We aimed to investigate whether contrast-enhanced ultrasound (CEUS) could be useful for early evaluation of the treatment response to transcatheter arterial chemoembolization (TACE) of hepatocellular carcinoma (HCC).

METHODS

This study retrospectively selected HCCs in which homogeneous retention of iodized oil was confirmed on non-contrast-enhanced computed tomography performed immediately after TACE. Therapeutic responses of HCCs were evaluated by CEUS 1 to 2 days after TACE and by contrast-enhanced computed tomography (CECT) approximately 4 weeks after TACE. We investigated the noninferiority of CEUS 1 to 2 days after TACE to CECT approximately 4 weeks after TACE in terms of the diagnostic accuracy of the therapeutic response to TACE on HCC.

RESULTS

Eighty-nine HCCs were enrolled in this study between April 2014 and June 2016. A complete response was observed in 57 of 89 nodules (64.0%), and an incomplete response was observed in the remaining 32 nodules (36.0%). The accuracy rates for CEUS 1 to 2 days after TACE and CECT approximately 4 weeks after TACE in the therapeutic effect of TACE on HCCs were 83.1% (95% confidence interval, 73.7%-90.2%) and 83.1% (95% confidence interval, 73.7%-90.2%), respectively. The difference in diagnostic accuracy between methods was 0%, which was below the predetermined noninferiority limit of 15%, and CEUS 1 to 2 days after TACE was noninferior to CECT approximately 4 weeks after TACE.

CONCLUSIONS

Our results suggest that CEUS is a useful modality for early therapeutic evaluation of TACE for HCC, and we can thus plan the next treatment strategies for HCC within a few days after TACE.

Comparative analysis of tumor-associated vascular changes following TACE alone or in combination with sorafenib treatment in HCC: A retrospective study

The objective of the present study was to investigate the tumor-associated vascular changes in hepatocellular carcinoma (HCC) following treatment with transarterial chemoembolization (TACE) combined with sorafenib. The data of 20 patients were retrospectively analyzed. Patients underwent treatment depending on their chosen regimens (orally administered sorafenib was recommended, however the cost prevented some study articipants from selecting this course). Based on this, the patients were divided into TACE combined with sorafenib (TS) (n=10) and TACE-only treatment groups (n=10). Digital subtraction angiography images of all patients were analyzed by 2 radiologists who were blind to the type of treatment administered. The diameters of the hepatic and proper hepatic arteries, and hepatic artery branches (tumor-associated arteries), the splenic, left gastric and gastroduodenal arteries or portal veins (non-tumor-associated arteries) and the number of microvascular vessels were compared prior to and following sorafenib treatment in the TS group, between the first and second sessions of TACE in the TACE-only group and between the TS and TACE-only groups. In the TS group, the diameters of the hepatic and proper hepatic arteries, their branches and the number of microvascular vessels were significantly decreased following sorafenib treatment (P<0.05), while the diameters of the splenic, gastroduodenal and left gastric arteries were not significantly altered (P>0.05). In the TACE-only group, the diameters of the hepatic, proper hepatic, splenic, left gastric and gastroduodenal arteries were not significantly different between the first and second TACE sessions (P>0.05), while the diameters of the hepatic artery branches and the number of microvascular vessels were significantly altered (P<0.05). TACE combined with sorafenib significantly decreased the diameters of the tumor-associated arteries and the number of tumor microvascular vessels when compared with TACE treatment alone (P<0.05). No significant difference in the diameters of the portal vein and its branches between the two groups was observed (P>0.05). Treatment with TACE combined with sorafenib may significantly affect the tumor-associated vasculature compared with treatment with TACE alone in HCC.

Contrast-enhanced harmonic endoscopic ultrasonography for differential diagnosis of localized gallbladder lesions

BACKGROUND AND AIM

Differential diagnosis of localized gallbladder lesions is challenging. The aim of the present study was to evaluate the utility of contrast-enhanced harmonic endoscopic ultrasonography (CH-EUS) for diagnosis of localized gallbladder lesions.

METHODS

One hundred and twenty-five patients with localized gallbladder lesions were evaluated by CH-EUS between March 2007 and February 2014. This was a single-center retrospective study. Utilities of fundamental B-mode EUS (FB-EUS) and CH-EUS in the differentiation of gallbladder lesions and sludge plug were initially compared. Thereafter, these two examinations were compared with respect to their accuracy in the diagnosis of malignant lesions. Five reviewers blinded to the clinicopathological results evaluated microcirculation patterns in the vascular and perfusion images.

RESULTS

In the differentiation between gallbladder lesions and sludge plug, FB-EUS had a sensitivity, specificity, and accuracy of 82%, 100%, and 95%, respectively, whereas CH-EUS had a sensitivity, specificity, and accuracy of 100%, 99%, and 99%, respectively. FB-EUS-based diagnosis of carcinomas based on tumor size and/or shape had a sensitivity, specificity, and accuracy of 61-87%, 71-88%, and 74-86%, respectively. Additional information regarding irregular vessel patterns in the vascular image and/or heterogeneous enhancement in the perfusion image on CH-EUS increased the sensitivity, specificity, and accuracy for the diagnosis of carcinomas to 90%, 98%, and 96%, respectively. There was a significant difference between FB-EUS and CH-EUS in terms of carcinoma diagnosis.

CONCLUSION

CH-EUS was useful for the evaluation of localized gallbladder lesions.

Evaluation of transcatheter arterial embolization therapy on hepatocellular carcinomas using contrast-enhanced harmonic power Doppler sonography: comparison with CT, power Doppler sonography, and dynamic MRI

PURPOSE

The aim of this study was to assess and compare the sensitivity of power Doppler sonography, contrast-enhanced sonography, plain computed tomography (CT), and dynamic magnetic resonance imaging (MRI) for detecting hepatocellular carcinoma (HCC) nodules incompletely treated with transcatheter arterial embolization (TAE).

METHODS

A total of 63 unresectable HCC nodules were examined in this study. The HCCs were treated with TAE. All patients underwent plain CT, power Doppler sonography, contrast-enhanced harmonic power Doppler sonography, and dynamic MRI 1 week after TAE. The sensitivity of each modality to incompletely treated HCC nodules was compared. Detection of the residual viable HCC on angiography or tumor biopsy was regarded as the gold standard for the diagnosis of incomplete treatment.

RESULTS

Twenty-four nodules (38%) were diagnosed as incompletely treated. The sensitivities of plain CT, power Doppler sonography, contrast-enhanced harmonic power Doppler sonography, and dynamic MRI to these incompletely treated nodules were 42% (10/24), 46% (11/24), 88% (21/24), and 79% (19/24), respectively. Eighty percent (19 nodules) of the 24 incompletely treated nodules were located within a depth of less than 8 cm. The sensitivities of plain CT, power Doppler sonography, contrast-enhanced harmonic power Doppler sonography, and dynamic MRI to these superficial incompletely treated nodules were 37% (7/19), 53% (10/19), 100% (19/19), and 74% (14/19), respectively. In contrast, the sensitivities of each modality to deeply located nodules were 60% (3/5), 20% (1/5), 40% (2/5), and 100% (5/5), respectively.

CONCLUSION

Plain CT and power Doppler sonography had a low sensitivity to HCC nodules incompletely treated with TAE. Except for those that were deeply located, contrast-enhanced harmonic sonography showed the highest sensitivity in detecting incompletely treated HCC nodules.

Detection of tumor vascularity in hepatocellular carcinoma with contrast-enhanced Dynamic Flow imaging: Comparison with contrast-enhanced power Doppler imaging

OBJECTIVE

To compare the effectiveness of contrast-enhanced Dynamic Flow imaging and contrast-enhanced power Doppler imaging using Levovist(®) as a microbubble contrast agent in evaluating intratumoral vascularity in hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

Twenty-nine patients with 54 hepatocellular carcinoma nodules (before treatment, 31; after treatment, 23) were studied with both Dynamic Flow and power Doppler imaging with intravenous injection of Levovist(®). Tumor vascularity was categorized as 0, no blood flow signals within the tumor; 1, dotlike blood flow signals within the tumor; 2, moderate blood flow signals within the tumor; and 3, abundant blood flow signals within the tumor. Detectability of intratumoral vascularity of hepatocellular carcinoma in three groups based on tumor depth, blooming and noise artifacts on contrast-enhanced Dynamic Flow and contrast-enhanced power Doppler imaging were also compared with results obtained using dynamic CT as a the gold standard. The effectiveness of contrast-enhanced Dynamic Flow and contrast-enhanced power Doppler imaging in assessing therapeutic effect were compared at the same time.

RESULTS

The ability of contrast-enhanced Dynamic Flow Doppler imaging to detect tumor vascularity in the superficial and intermediate hepatocellular carcinoma groups was close to that of contrast-enhanced power Doppler imaging (p>0.05). However, contrast-enhanced Dynamic Flow imaging demonstrated tumor parenchymal stain in 28 hepatocellular carcinoma nodules (61%), which was not detected by contrast-enhanced power Doppler imaging. Further, significantly fewer artifacts appeared in contrast-enhanced Dynamic Flow imaging than in contrast-enhanced power Doppler imaging (p<0.001). In assessing therapeutic response, the sensitivity of contrast-enhanced Dynamic Flow imaging was similar to that of dynamic CT. In deep areas, however, those more than 6 cm below the surface of the body, contrast-enhanced Dynamic Flow imaging was less sensitivity than contrast-enhanced power Doppler imaging (p=0.005).

CONCLUSION

Contrast-enhanced Dynamic Flow imaging provides an effective approach to assessing intratumoral vascularity and therapeutic response in HCC lesions situated less than 6 cm from the surface of the body. It is superior to contrast-enhanced power Doppler imaging in its ability to detect tumor parenchymal stain and production of fewer artifacts.

Qualitative diagnosis of hepatocellular carcinoma by contrast enhanced ultrasonography using Coded Harmonic Angio with Levovist

We attempted to evaluate diagnosis and characterization and to access therapeutic effects in cases of hepatocellular carcinoma (HCC) by contrast enhanced ultrasound (CEUS) using Coded Harmonic Angio (CHA) with Levovist, an intravenous ultrasound contrast agent. Fifty-seven HCC foci in 39 patients, including 37 HCC foci in 28 patients before and after transcatheter arterial chemoembolization or radio frequency ablation, were examined by CEUS using the CHA mode, which is under development. This mode uses digitally encoded pulse sequences that identify and suppress nonmoving tissue signals and enhance contrast signals from Levovist in a gray-scale format. In all cases, abundant tortuous intratumoral blood flow was visualized in the early vascular phase by continuous transmission, while tumor stain was recognized by consecutive 1-to-2 second intermittent transmission. Residual tumor area after treatment was also clearly depicted by intratumoral blood flow and partial enhancement. CEUS using CHA with Levovist is likely to become important in the qualitative diagnosis of hepatic tumor and to improve the efficacy of treatment for HCC.

Efficacy of a microballoon catheter in transarterial chemoembolization of hepatocellular carcinoma using miriplatin, a lipophilic anticancer drug: Short-term results

AIM

The goal of the study was to evaluate the efficacy and safety of balloon-occluded transarterial chemoembolization (B-TACE) of hepatocellular carcinoma (HCC) using miriplatin (a lipophilic anticancer drug) and gelatin particles.

METHODS

B-TACE was performed for 62 HCC nodules in 33 patients who could not be treated by surgical resection or radiofrequency ablation. All 33 patients had a history of transarterial chemoembolization (TACE) treatment prior to B-TACE. As a historical comparison, we investigated 40 nodules in 28 patients treated by TACE using a conventional microcatheter (C-TACE), miriplatin and gelatin particles. The therapeutic effect per tumor was compared between the groups based on the Response Evaluation Criteria in Cancer Study Group of Japan (RECICL) and side-effects were compared based on the Common Terminology Criteria for Adverse Events (ver. 4.0).

RESULTS

The therapeutic efficacy after 4-12 weeks was evaluated in 59 nodules in the B-TACE group and in 37 nodules in the C-TACE group. Of these nodules, TE4 occurred in 29 (49.2%) in the B-TACE group and in 10 (27%) in the C-TACE group. Local efficacy was significantly higher in nodules treated by B-TACE than by C-TACE. The side-effects on hepatic function were similar in the two groups.

CONCLUSION

Our results suggest that B-TACE with miriplatin is a useful treatment for hepatocellular carcinoma.

Use of contrast-enhanced ultrasonography with a perflubutane-based contrast agent performed one day after transarterial chemoembolization for the early assessment of residual viable hepatocellular carcinoma

OBJECTIVE

We evaluated the efficacy of contrast-enhanced ultrasonography (US), compared with contrast-enhanced computed tomography (CT), for early assessments after transarterial chemoembolization (TACE) for the treatment of hypervascular hepatocellular carcinoma (HCC) lesions.

SUBJECTS AND METHODS

Thirty-two patients with 59 HCC lesions who were scheduled to receive TACE were enrolled in this prospective study. TACE was performed by injecting a mixture of iodized oil and miriplatin hydrate, followed by a gelatin sponge. Digital subtraction angiography (DSA) and/or contrast-enhanced CT were performed 2-6 months after TACE and were used as the reference standard for residual HCC; the detection rates for residual viable HCC using contrast-enhanced US with a perflubutane-based contrast agent and a high mechanical index (MI) mode performed one day after TACE were also compared with those obtained using contrast-enhanced CT performed one month after TACE. The comparisons were made using the McNemar test.

RESULTS

Forty-seven (79.7%) of the 59 HCC lesions were diagnosed as having residual viability based on DSA and contrast-enhanced CT findings obtained 2-6 months after TACE. Eight (17.0%) of the 47 HCC lesions that were diagnosed as having residual viability using one-day contrast-enhanced US were not detected using one-month contrast-enhanced CT because of artifacts produced by the high attenuation of the iodized oil. The detection rate for residual HCC lesions using one-day contrast-enhanced US (95.7%, 45/47) was significantly higher than that using one-month contrast-enhanced CT (78.7%, 37/47) (P<0.05).

CONCLUSION

Contrast-enhanced US performed one day after TACE is more sensitive than contrast-enhanced CT performed one month after TACE for detecting residual viable HCC.

Therapeutic response assessment of transcatheter arterial chemoembolization for hepatocellular carcinoma: ultrasonography, CT and MR imaging

Two randomized controlled trials identified that transcatheter arterial chemoembolization (TACE) for hepatocellular carcinoma (HCC) shows a significant survival benefit compared with controls, after a long-term controversy. Thus, TACE is the current standard of care for patients presenting with multinodular HCC. Monitoring tumor response to TACE is part of the clinical management of HCC patients. Imaging, including ultrasonography, computed tomography and magnetic resonance imaging, has an important role in assessing therapeutic effects earlier and more objectively. Imaging assessment needs to detect not only a reduction in overall tumor load but also a reduction in viable tumor. Here, we give an overview of the current status of the imaging assessment of HCC response to TACE.

Short-term evaluation of liver tumors after transarterial chemoembolization: limitations and feasibility of contrast-enhanced ultrasonography

PURPOSE

To evaluate the limitations and the feasibility of contrast-enhanced ultrasonography (CEUS) for the assessment of tumor response shortly after transarterial chemoembolization (TACE).

MATERIALS AND METHODS

Fifty seven patients (41 patients with hepatomas, 16 patients with metastases) were studied with CEUS before, 1 day after, and 30 days after TACE. A CEUS-efficiency score (CEUS-ES) was calculated, which evaluated: (a) the completeness of visualization of the target tumor(s) (2: good, 1: adequate, 0: poor) and (b) the quality of delineation of post-TACE necroses (2: good, 1: adequate, 0: poor). A CEUS study was considered as "diagnostic," if each of the aforementioned parameters was associated with grade 1 or 2.

RESULTS

CEUS studies were "diagnostic" in 36/57 patients (63.1%). Patients with hepatomas were more likely to undergo "diagnostic" CEUS than patients with metastases (70.7% vs. 43.7%, P = 0.0728). Lesions' multiplicity, deep location, hypoenhancement on pretreatment CEUS, and diffuse growth had a statistically significant (P < 0.05) negative impact on CEUS-ES. Hyperechogenicity on pre-treatment, unenhanced US had a non-statistically significant (P = 0.176) negative impact. Differences between "diagnostic" CEUS studies and CT/MR regarding detection of residual tumor were insignificant (P = 0.8178).

CONCLUSION

The percentage of lesions which are unsuitable for post-TACE evaluation with CEUS is not negligible. For the rest, the respective role of CEUS is promising.

Contrast-enhanced ultrasound-guided microwave ablation for hepatocellular carcinoma inconspicuous on conventional ultrasound

OBJECTIVE

To evaluate the efficiency and feasibility of contrast-enhanced ultrasound (CEUS)-guided microwave ablation for hepatocellular carcinoma inconspicuous on conventional US.

MATERIALS AND METHODS

From March 2006 to February 2010, 107 patients (93 male, 14 female; mean age 58.9±11.0 years) with 107 hepatocellular carcinoma (HCC) nodules (mean maximum diameter 19.5±8.5 mm) inconspicuous on conventional US underwent microwave (MW) ablation under CEUS guidance in this study. US contrast agent was SonoVue (Bracco, Milan, Italy), a second-generation contrast agent. CEUS was performed first, and then MW ablation was carried out by means of CEUS guidance under unconscious intravenous anaesthesia if the tumours were displayed on CEUS.

RESULTS

105 tumours were successfully visualised on CEUS by using 1-2 times contrast agent injection and MW ablation was performed under CEUS guidance. The technical success rate was 98.13% (105/107). The number of antenna insertions for each tumour was 1.89±0.92, and the mean session of MW ablation for each tumour was 1.08±0.28. The mean duration of energy application for each tumour was 7.05±4.03 min. The follow-up time was 12-54 months (median 18 months). The technique effectiveness rate was 99.05% (104/105). The local tumour progression rate was 1.9% (2/105). There were no severe complications in any patients.

CONCLUSION

CEUS-guided MW ablation is an efficient and feasible treatment method for patients with hepatocellular carcinoma inconspicuous on conventional US.

Contrast-enhanced sonography-guided radiofrequency ablation for the local recurrence of previously treated hepatocellular carcinoma undetected by B-mode sonography

BACKGROUND.: The purpose of this study was to assess the usefulness of contrast-enhanced sonography (CEUS) with Sonazoid to demonstrate local recurrence of hepatocellular carcinoma previously treated with radiofrequency ablation (RFA) and not seen on conventional sonography, prior to repeat RFA. METHODS.: This study included 16 cirrhotic patients with 17 cases of hypervascular locally recurrent hepatocellular carcinoma found by contrast-enhanced multidetector row CT (MDCT) but not seen on noncontrast sonography. We used Kupffer-phase imaging and vascular-phase imaging after re-injection. The morphologic patterns of local recurrence detected on CEUS were compared with those on MDCT. We performed repeat RFA guided by CEUS using Kupffer-phase imaging after re-injection. RESULTS.: We were able to detect on CEUS the location of all local recurrences with positive enhancement after re-injection. The morphologic patterns of local recurrence on CEUS were in concordance with those found on MDCT in all lesions. Repeat percutaneous RFA was successfully performed in all lesions. CONCLUSIONS.: The CEUS appearance of local recurrences correlated well with those on MDCT. A wider use of CEUS to guide repeat of percutaneous RFA may be possible with Sonazoid.

Contrast enhanced ultrasound of hepatocellular carcinoma

Sonazoid (Daiichi Sankyo, Tokyo, Japan), a second-generation of a lipid-stabilized suspension of a perfluorobutane gas microbubble contrast agent, has been used clinically in patients with liver tumors and for harmonic gray-scale ultrasonography (US) in Japan since January 2007. Sonazoid-enhanced US has two phases of contrast enhancement: vascular and late. In the late phase of Sonazoid-enhanced US, we scanned the whole liver using this modality at a low mechanical index (MI) without destroying the microbubbles, and this method allows detection of small viable hepatocellular carcinoma (HCC) lesions which cannot be detected by conventional US as perfusion defects in the late phase. Re-injection of Sonazoid into an HCC lesion which previously showed a perfusion defect in the late phase is useful for confirming blood flow into the defects. High MI intermittent imaging at 2 frames per second in the late phase is also helpful in differentiation between necrosis and viable hypervascular HCC lesions. Sonazoid-enhanced US by the coded harmonic angio mode at a high MI not only allows clear observation of tumor vessels and tumor enhancement, but also permits automatic scanning with Sonazoid-enhanced three dimensional (3D) US. Fusion images combining US with contrast-enhanced CT or contrast-enhanced MRI have made it easy to detect typical or atypical HCC lesions. By these methods, Sonazoid-enhanced US can characterize liver tumors, grade HCC lesions histologically, recognize HCC dedifferentiation, evaluate the efficacy of ablation therapy or transcatheter arterial embolization, and guide ablation therapy for unresectable HCC. This article reviews the current developments and applications of Sonazoid-enhanced US and Sonazoid-enhanced 3D US for diagnosing and treating hepatic lesions, especially HCC.

Contrast-enhanced ultrasonography of hepatocellular carcinoma after chemoembolisation using drug-eluting beads: a pilot study focused on sustained tumor necrosis

The purpose of this study was to assess the use of contrast-enhanced ultrasonography (CEUS) and the sustained antitumor effect of drug-eluting beads used for transarterial chemoembolisation (TACE) of unresectable hepatocellular carcinoma (HCC). Ten patients with solitary, unresectable HCC underwent CEUS before, 2 days after, and 35 to 40 days after TACE using a standard dose (4 ml) of drug-eluting beads (DC Beads; Biocompatibles, Surrey, UK) preloaded with doxorubicin (25 mg doxorubicin/ml hydrated beads). For CEUS, a second-generation contrast agent (SonoVue, Bracco, Milan, Italy) and a low mechanical-index technique were used. A part of the tumor was characterized as necrotic if it showed complete lack of enhancement. The percentage of necrosis was calculated at the sonographic section that depicted the largest diameter of the tumor. Differences in the extent of early (2 days after TACE) and delayed (35 to 40 days after TACE) necrosis were quantitatively and subjectively assessed. Early post-TACE tumor necrosis ranged from 21% to 70% (mean 43.5% +/- 19%). There was a statistically significant (p = 0.0012, paired Student t test) higher percentage of delayed tumor necrosis, which ranged from 24% to 88% (mean 52.3% +/- 20.3%). Subjective evaluation showed a delayed obvious increase of the necrotic areas in 5 patients. In 2 patients, tumor vessels that initially remained patent disappeared on the delayed follow-up. A part of tumor necrosis after chemoembolisation of HCC with DEB seems to take place later than 2 days after TACE. CEUS may provide evidence for the sustained antitumor effect of DEB-TACE. Nevertheless, the ideal time for the imaging evaluation of tumor response remains to be defined.

Ablation therapy guided by contrast-enhanced sonography with Sonazoid for hepatocellular carcinoma lesions not detected by conventional sonography

OBJECTIVE

We evaluated the usefulness of contrast-enhanced harmonic gray scale sonography with a newly developed sonographic contrast medium as a means of guidance for percutaneous ablation therapy of hepatocellular carcinoma lesions not detected by conventional sonography.

METHODS

We examined 85 patients with 108 hepatocellular carcinoma lesions that were identified as hypervascular by multidetector-row computed tomography by using contrast-enhanced harmonic gray scale sonography after injection of Sonazoid (GE Healthcare, Oslo, Norway), a lipid-stabilized suspension of a perfluorobutane gas microbubble contrast agent. We scanned the whole liver by this modality at a low mechanical index in the late phase to detect lesions not detected by conventional sonography and then scanned the lesions again by this modality at a high mechanical index to visualize tumor vessels and enhancement. We also performed percutaneous ablation therapy guided by this modality to treat viable hepatocellular carcinoma lesions that could not be detected by conventional sonography.

RESULTS

Conventional sonography identified 90 (83%) of 108 hepatocellular carcinoma lesions; 15 (14%) additional viable lesions not detected by conventional sonography were detected in the late phase of contrast-enhanced harmonic gray scale sonography at a low mechanical index, and tumor vessels and enhancement were observed in the late phase at a high mechanical index. Contrast-enhanced harmonic gray scale sonography diagnosed 105 (97%) of the 108 viable hepatocellular carcinoma lesions, and 14 (93%) of the 15 lesions not detected by conventional sonography were successfully treated by percutaneous ablation therapy guided by this modality.

CONCLUSIONS

Contrast-enhanced harmonic gray scale sonography is useful for guidance of percutaneous ablation therapy of hepatocellular carcinoma lesions not detected by conventional sonography.

Diagnosis of gallbladder diseases by contrast-enhanced phase-inversion harmonic ultrasonography

We evaluated the usefulness of contrast-enhanced ultrasonography(US) for detecting and differentiating gallbladder lesions. Contrast-enhanced coded phase-inversion harmonic US was performed on 90 patients with gallbladder abnormalities. After administering Levovist, we observed the gallbladders in real time. Contrast-enhanced coded phase-inversion harmonic ultrasonography was compared with B-mode US and contrast-enhanced computer tomography (CT) with regard to the sensitivity and specificity in depicting the elevated gallbladder lesions. Furthermore, we assessed how the vascular patterns of the elevated gallbladder lesions depicted by contrast-enhanced US correlated with the diagnosis. Contrast-enhanced US efficiently discriminated true lesions from biliary sludge, unlike B-mode US. Consequently, contrast-enhanced US was more specific (100%) than B-mode US (81%), although their sensitivities were similar (98% and 96%, respectively). Contrast-enhanced US was also more sensitive that contrast-enhanced CT (98% versus 79%), although the two methods were equally sensitive (100% versus 95%). We classified the vascular patterns of the abnormalities depicted by contrast-enhanced US in the 90 cases into types 1 to 4, which represent branch-like, heterogeneous, homogeneous, and avascular patterns, respectively. All type 1 and 2 lesions were over 10 mm in size while most (88%) type 3 lesions were 10 mm or less in size. While the majority of carcinomas (86%) were type 1 or 2, three benign lesions also showed these patterns. Thus, the vascular pattern may simply reflect the size of the lesion and therefore its usefulness in diagnosing gallbladder lesions may be limited. Nevertheless, contrast-enhanced US is clearly superior to the other techniques in discriminating biliary sludge from other lesions.

Contrast-enhanced Ultrasound as a Predictor of Treatment Efficacy within 2 Weeks after Transarterial Chemoembolization of Hepatocellular Carcinoma

PURPOSE

To determine whether contrast-enhanced ultrasound (CEUS) can aid in assessing treatment efficacy within the first 2 weeks after transarterial chemoembolization for hepatocellular carcinoma.

MATERIALS AND METHODS

Contrast-enhanced ultrasound was performed to detect residual tumor blood flow after 42 transarterial chemoembolization procedures in 33 patients who had hepatocellular carcinomas, and the results were compared with final tumor outcome. Twenty-nine CEUS studies were performed within 2 weeks after treatment and the remainder within 1 month. Phase-inversion low-mechanical-index real-time and intermittent imaging were performed after the intravenous injection of 0.5-2 mL US contrast medium by experienced radiologists blind to all other imaging findings.

RESULTS

Nine tumors did not reach final outcome--patients were lost to follow-up or died without autopsy (n = 6) or tumors were retreated before final outcome was established (n = 3). Of the remaining 33 tumors, outcome was established by histology (n = 9), angiography (n = 14), tumor growth (n = 2), or by computed tomography and/or magnetic resonance imaging performed more than 6 months after treatment (n = 8). Twenty-three tumors were studied by CEUS within 2 weeks and 10 within 1 month after treatment. Of these 33 tumors, there were no false-negative results and one false-positive result. The only error occurred when the CEUS study was performed within 1 day after treatment.

CONCLUSIONS

Residual tumor blood flow on CEUS performed at 2 or more days after transarterial chemoembolization may be predictive of tumor outcome that currently requires 3 months to be reliably detected by computed tomography and/or magnetic resonance imaging.

Prospective study of differential diagnosis of hepatic tumors by pattern-based classification of contrast-enhanced sonography

AIM: To prospectively evaluate the usefulness of a pattern-based classification of contrast-enhanced sonographic findings for differential diagnosis of hepatic tumors.

METHODS: We evaluated the enhancement pattern of the contrast-enhanced sonography images in 586 patients with 586 hepatic lesions, consisting of 383 hepatocellular carcinomas, 89 metastases, and 114 hemangiomas. After injecting a galactose-palmitic acid contrast agent, lesions were scanned by contrast-enhanced harmonic gray-scale sonography in three phases: arterial, portal, and late. The enhancement patterns of the initial 303 lesions were classified retrospectively, and multiple logistic regression analysis was used to identify enhancement patterns that allowed differentiation between hepatic tumors. We then used the pattern-based classification of enhancement we had retrospectively devised to prospectively diagnose 283 liver tumors.

RESULTS: Seven enhancement patterns were found to be significant predictors of different hepatic tumors. The presence of homogeneous or heterogeneous enhancement both in the arterial and portal phase was the typical enhancement pattern for hepatocellular carcinoma, while the presence of peritumoral vessels in the arterial phase and ring enhancement or a perfusion defect in the portal phase was the typical enhancement pattern for metastases, and the presence of peripheral nodular enhancement both in the arterial and portal phase was the typical enhancement pattern for hemangioma. The sensitivity, specificity, and accuracy of prospective diagnosis based on the combinations of enhancement patterns, respectively, were 93.2%, 96.2%, and 94.0% for hepatocellular carcinoma, 87.9%, 99.6%, and 98.2% for metastasis, and 95.6%, 94.1%, and 94.3% for hemangioma.

CONCLUSION: The pattern-based classification of the contrast-enhanced sonographic findings is useful for differentiating among hepatic tumors.

Real-time blood-pool images of contrast enhanced ultrasound with Definity in the detection of tumour nodules in the liver

Lower mechanical index (MI) technique with newer microbubble agents has been introduced into clinical practice as a newer ultrasound (US) imaging. However, the efficacy in detecting tumour nodules has not been proven scientifically. The aim of this study was to elucidate the efficacy of a blood-pool image of real-time contrast-enhanced US under low MI in detecting liver tumours. 15 rabbits with VX-2 tumour were used; the number of implantations was none in two rabbits, one in four, two in five and three in four. US equipment was APLIO (Toshiba) with linear probe (3.5/7.0 MHz). The number, location and size of tumour nodules were examined by non-contrast tissue harmonic imaging (NC-US) or contrast-enhanced pulse subtraction harmonic imaging (C-US) under extra-low MI (MI 0.065) with the injection of Definity (30 microl kg(-1)). The number of tumour nodules detected by both NC-US and C-US were consistent with the histopathological results in five rabbits - two with none, two with one nodule and one with two nodules. In the other 10 rabbits, C-US showed all the implanted tumours and small daughter nodules around them that were confirmed by histopathology. However, NC-US failed to demonstrate two implanted nodules and all the daughter nodules. On the basis of the histopathological results, detectability of implanted tumour was not significantly different between NC-US (24/26, 92.3%) and C-US (26/26, 100%). However C-US was superior to NC-US in delineating the nodules and in detecting small daughter nodules. The sizes of the implanted tumour nodules measured by histopathology correlated closely with those measured by C-US. Real-time blood-pool images by pulse subtraction harmonic imaging under extra-low MI with Definity will contribute to the improvement of the ultrasound delineation and detection of liver tumours.

Advanced dynamic flow imaging with contrast-enhanced ultrasonography for the evaluation of tumor vascularity in liver tumors

To examine the usefulness of advanced dynamic flow imaging in diagnosing hepatic tumor and in assessing therapeutic effects in patients with hepatocellular carcinoma (HCC) and metastatic hepatic tumor, we performed contrast-enhanced ultrasonography (US) with Levovist, a microbubble contrast agent. Twenty-two patients of 35 HCC nodules infected with hepatitis C virus (HCV) and six patients with metastatic liver nodules were studied. They were diagnosed as having HCC or metastasis with helical dynamic computed tomography (CT) and/or celiac angiography. Tumor vascularities in the early arterial and postvascular phases were assessed by real-time scanning of advanced dynamic flow imaging and intermittent interval-delay scanning of contrast pulse subtraction imaging with a wide-band power Doppler technology. All patients showed hypervascular enhancement of HCC on contrast-enhanced US and/or dynamic CT. The advanced dynamic flow could be obtained as vascular and perfusion images of hepatic tumors. Tumor vascularities, including tumor vessels and parenchymal flow, were able to demonstrate in 27 of 29 nodules including 17 patients with 27 HCC nodules and 2 patients with 2 metastatic nodules before radiofrequency ablation (RFA) treatment by the advanced dynamic flow on contrast-enhanced harmonic US. Two nodules gave insufficient dynamic flow which were located approximately 12 cm in depth from the body surface. The advanced dynamic flow, which was done 7-10 days after RFA, indicated disappearance of the tumor vessels in 27 of visible 27 nodules. The study on early phase of helical dynamic CT revealed the same results as noted in early vascular phase of dynamic flow US. No major complication of RFA procedure was noted. The results indicated that contrast-enhanced advanced dynamic flow imaging on US clearly depicted intratumoral vascularity in real time and thus it is useful to diagnose and assess therapeutic efficacy in patients with HCC and metastatic liver tumor.

Treatment of hepatocellular carcinoma with percutaneous radiofrequency ablation: usefulness of contrast harmonic sonography for lesions poorly defined with B-mode sonography

OBJECTIVE

The purpose of this study was to assess the usefulness of contrast harmonic sonography guidance in percutaneous radiofrequency ablation of hepatocellular carcinomas that could not be adequately depicted by B-mode sonography. SUBJECTS AND METHODS. Twenty-one patients with 21 hepatocellular carcinomas prospectively underwent radiofrequency ablation treatment with contrast harmonic sonography as guidance. Twenty-five patients with 25 hepatocellular carcinomas were retrospectively selected as the historical control group under the same conditions as the study group; the control group patients were treated under B-mode sonography guidance.

RESULTS

Twenty (95.2%) of the 21 patients were successfully treated during a single treatment session, and the remaining patient (4.8%) required two treatment sessions with contrast harmonic guidance. On the other hand, only eight (32%) of the 25 control subjects were successfully treated during a single treatment session using B-mode sonographic guidance without contrast imaging. The difference between these two groups was statistically significant (p = 0.002).

CONCLUSION

Contrast harmonic sonography helps in the placement of radiofrequency ablation electrodes in hypervascular hepatocellular carcinomas that cannot be adequately depicted by B-mode sonography.

Role of additional angiography and chemoembolization in patients with hepatocellular carcinoma who achieved complete necrosis following transarterial chemoembolization

BACKGROUND AND AIMS

Although transarterial chemoembolization (TACE) has been reported to have antitumor effects in patients with hepatocellular carcinoma (HCC), optimal time schedules and follow-up methods have not yet been determined. We therefore prospectively analyzed the effects of additional angiography and chemoembolization on HCC recurrence and survival in patients who underwent TACE and achieved complete necrosis (CN).

METHODS

A total of 68 patients who achieved CN after TACE, as assessed using dynamic computed tomography (CT), were randomized into two groups. Patients in the CT group (n = 34) were followed using dynamic CT every 3 months without any further intervention, whereas patients in the angiography group (n = 34) received additional angiography 1 month after achievement of CN. We compared overall survival and disease-free survival between the two groups and analyzed the benefit of additional angiography.

RESULTS

The cumulative recurrence rate did not differ between the angiography and CT groups (55%vs 48% at 12 months and 66%vs 67% at 24 months, P = 0.92). The overall survival rates at 12 and 24 months were 88% and 84% in the angiography group, and 88% and 70% in the CT group, respectively (P = 0.57). Of the 34 patients in the angiography group, 27 (79%) suffered from adverse reactions of additional angiography and subsequent chemoembolization, seven (20.6%) experienced serum bilirubin increases of >/=1 mg/dL over baseline, and two (5.9%) developed renal impairment.

CONCLUSION

Additional angiography and chemoembolization did not reduce tumor recurrence or improve patient survival in HCC patients who achieved CN, as assessed using dynamic CT, following TACE.

Surgical management of hepatic malignancy

Over the past twenty-five years, hepatic resection has evolved from a high risk, resource-intensive procedure with limited application to a safe and commonly performed operation with broad indications. This period has seen dramatic improvements in perioperative outcome, including reductions in mortality, blood loss, transfusion rates, and hospital stay. These improved perioperative results are largely responsible for the emergence of hepatic resection as a viable and effective treatment option for selected patients with 1 degree and 2 degrees hepatobiliary malignancy. Continued advances in imaging technology, along with a heightened awareness of the clinical and tumor-related variables that dictate outcome, have allowed better preoperative assessment of disease extent and improved patient selection. Advances in other areas, such as minimally invasive and ablative techniques, have increased the treatment options and have had some impact on the approach to patients with malignant hepatobiliary disease; however, resection remains the most effective therapy. Although the long term results after resection are better than with other modalities, recurrence rates remain high, and further improvements in survival will require more effective systemic agents. As better adjuvant and neo-adjuvant therapies emerge, the results of resection are likely to improve and the indications for its application perhaps will extend to patients currently considered to have unresectable disease.

Differential diagnosis of hepatic tumors by using contrast enhancement patterns at US

PURPOSE

To assess the accuracy of pattern-based classification of contrast material-enhanced wideband harmonic gray-scale ultrasonographic (US) images in the differential diagnosis of hepatic tumors.

MATERIALS AND METHODS

A total of 183 hepatic lesions in 183 patients were studied; lesions included 116 hepatocellular carcinomas, 42 liver metastases, and 25 liver hemangiomas. After injection of a galactose-palmitic acid contrast agent, lesions were scanned with contrast-enhanced wideband harmonic gray-scale US in the arterial, portal venous, and late venous phases. The enhancement patterns were classified, and multiple logistic regression analysis was used to identify diagnostic patterns that enabled differentiation between hepatic tumors.

RESULTS

Five enhancement patterns were found to be significant in predicting different hepatic tumors. In hepatocellular carcinomas, the presence of intratumoral vessels in the arterial phase and homogeneous or heterogeneous enhancement in the portal phase were the most typical patterns. In metastases, the absence of intratumoral vessels in the arterial phase and ring enhancement or a perfusion defect in the portal phase were the most typical patterns. In hemangiomas, the absence of intratumoral vessels in the arterial phase and peripheral nodular enhancement in the portal phase were the most typical patterns. The sensitivity, specificity, and accuracy of diagnosis based on combinations of enhancement patterns were, respectively, 94.8%, 94.0%, and 94.5% for hepatocellular carcinoma; 90.5%, 94.3%, and 93.4% for metastasis; and 88.0%, 99.4%, and 97.8% for hemangioma.

CONCLUSION

Contrast-enhanced wideband harmonic gray-scale US is a useful tool for differentiating among the hepatic tumors studied.

Extra-low acoustic power harmonic images of the liver with perflutren: novel imaging for real-time observation of liver perfusion

OBJECTIVE

The features of images below the extra-low mechanical index level were studied to elucidate a suitable mechanical index level for observing real-time and continuous harmonic images of rabbit livers with VX-2 tumors with the use of perflutren.

METHODS

Eight New Zealand White rabbits, 2 with healthy livers and 6 with VX-2 tumors, were examined by harmonic imaging (1.85 and 3.7 MHz) at a frame rate of 17 Hz under various mechanical index levels.

RESULTS

Real-time enhanced images of the liver were observed continuously in all rabbits. Vascular images were more clearly visualized at the low mechanical index level (mechanical index, 0.18) than at any other level. However, predominant enhanced images of the whole liver were observed only at the extra-low mechanical index level (mechanical index, 0.06). In VX-2 tumors, tumor vessels were shown more clearly at a low acoustic power level than at an extra-low level. The histologically proved area of viable tumor was enhanced as a stain in the tumor nodule at an extra-low mechanical index level.

CONCLUSIONS

Harmonic imaging under extra-low mechanical index levels with perflutren could provide real-time and continuous enhanced images of the liver, which would contribute to improvement of the diagnostic ability of contrast-enhanced sonography in liver diseases.

Therapeutic response evaluation of malignant hepatic masses treated by interventional procedures with contrast-enhanced agent detection imaging

OBJECTIVE

To assess the usefulness of microbubble contrast-enhanced agent detection imaging in evaluating the therapeutic response of malignant hepatic masses to treatment with interventional procedures.

METHODS

Fifty-eight patients with 68 hepatocellular carcinomas and 6 metastases who were treated with interventional procedures were evaluated with SH U 508A-enhanced agent detection imaging and helical computed tomography. Helical computed tomography was also performed to help establish the outcome of therapy with unenhanced computed tomography 2 weeks after transcatheter arterial chemoembolization and with dynamic contrast-enhanced computed tomography 1 day after radio frequency ablation or percutaneous ethanol injection. The studies were reviewed separately and randomly, and the sensitivity and specificity of agent detection imaging for detection of viable tumor residue were determined by follow-up imaging performed at least 3 months later.

RESULTS

Follow-up computed tomography or magnetic resonance imaging revealed complete tumor responses in 44 (59.5%) of 74 cases after the therapeutic procedures. The sensitivity of agent detection imaging was 94.7% after transcatheter arterial chemoembolization and 72.7% after radio frequency ablation and percutaneous ethanol injection. The specificity of agent detection imaging for the detection of residual tumors was 80% after transcatheter arterial chemoembolization and 79.2% after radio frequency ablation and percutaneous ethanol injection. The false-positive rate for agent detection imaging in cases of radio frequency ablation or percutaneous ethanol injection was 20.8% (5 of 24), resulting from reactive hyperemia or vascularity within the safety margin. In the assessment of the therapeutic effects, the concordance of contrast-enhanced agent detection imaging with helical computed tomography was statistically significant after transcatheter arterial chemoembolization (P < .00001) and radio frequency ablation or percutaneous ethanol injection (P < .02).

CONCLUSIONS

Contrast-enhanced agent detection imaging proved useful and as effective as helical computed tomography for evaluating the therapeutic effects of interventional therapeutic procedures for malignant hepatic masses.

Contrast-enhanced harmonic gray-scale sonographic-histologic correlation of the therapeutic effects of transcatheter arterial chemoembolization in patients with hepatocellular carcinoma

OBJECTIVE

We evaluated the usefulness of contrast-enhanced harmonic wideband gray-scale sonography in the assessment of the therapeutic effects of transcatheter arterial chemoembolization in patients with hepatocellular carcinoma and compared the performance of this imaging modality with the histologic findings for the patients.

SUBJECTS AND METHODS

Twenty-nine patients with 29 hepatocellular carcinoma lesions were examined. Tumor vascularity was evaluated before and 7 days after transcatheter arterial chemoembolization with contrast-enhanced harmonic wideband gray-scale sonography performed after injection of the contrast agent Levovist. Several biopsy specimens were obtained from the evaluated lesions, and the histologic findings were compared with the results of contrast-enhanced sonography.

RESULTS

Contrast-enhanced harmonic wideband gray-scale sonography performed after transcatheter arterial chemoembolization showed tumor vascularity in 16 of the 29 lesions, but none in the other 13 lesions. At histologic examination, 13 of the 16 lesions with tumor vascularity had residual tumor revealed, and the 13 lesions without tumor vascularity were found to have no histologically evident tumor residue, although three of these lesions showed tumor progression detected on CT during a 9- to 12-month follow-up period. Contrast-enhanced harmonic wideband gray-scale sonographic images were compared with the histologic findings as the gold standard, and the sensitivity and specificity of these images for discerning viable and nonviable hepatocellular carcinoma after transcatheter arterial chemoembolization were 100% and 81%, respectively.

CONCLUSION

Contrast-enhanced harmonic wideband gray-scale sonography is potentially useful for evaluating the therapeutic effects of transcatheter arterial chemoembolization on hepatocellular carcinoma.

Radiofrequency ablation of hepatocellular carcinoma: therapeutic response using contrast-enhanced coded phase-inversion harmonic sonography

OBJECTIVE

This study was performed to evaluate the usefulness of contrast-enhanced coded phase-inversion harmonic sonography in assessing the therapeutic response of percutaneous radiofrequency ablation in patients with hepatocellular carcinoma.

SUBJECTS AND METHODS

Sixty-seven patients with a total of 107 examinations on 91 hepatocellular carcinoma nodules underwent coded harmonic angio, a technique of coded phase-inversion harmonic sonography, using the IV microbubble contrast agent Levovist before and after percutaneous radiofrequency ablation. The intratumoral blood vessels and tumor parenchymal stain were detected in the early arterial phase and the late vascular phase, respectively. The results of contrast-enhanced imaging with coded harmonic angio were compared with those of three-phase dynamic CT.

RESULTS

Before treatment, all examined 107 hepatocellular carcinoma nodules were found to be hypervascular on contrast-enhanced imaging with coded harmonic angio. After radiofrequency ablation, contrast-enhanced coded harmonic angio detected persistent signal enhancement in 41 examined nodules (38.3%), whereas this technique showed no intratumoral enhancement in the remaining 66 (61.7%) examined nodules. Compared with dynamic CT, the sensitivity, specificity, and diagnostic accuracy of contrast-enhanced coded harmonic angio were 95.3%, 100%, and 98.1%, respectively. With contrast-enhanced coded harmonic angio, we found that it was difficult to identify the safety margin that can be detected on dynamic CT.

CONCLUSION

Contrast-enhanced imaging with coded harmonic angio may provide an alternative approach that has high diagnostic agreement with dynamic CT in assessing the therapeutic effect of radiofrequency ablation in hypervascular hepatocellular carcinomas, in spite of having limitations in identifying the safety margin.

Contrast enhancement patterns of hepatic tumours during the vascular phase using coded harmonic imaging and Levovist to differentiate hepatocellular carcinoma from other focal lesions

The purpose of the study was to assess contrast enhancement patterns of hepatic tumours during the vascular phase using contrast-enhanced ultrasound and Levovist to differentiate hepatocellular carcinoma from other hepatic tumours. 89 hepatic tumours in 82 consecutive patients were evaluated using coded harmonic ultrasound imaging. The procedure used a phase inversion harmonic technique and coded technology. We observed images for 2 min from the beginning of the administration as the vascular phase using continuous transmission and intermittent transmissions of 1 s or 2 s. The contrast agent Levovist was administered intravenously as a bolus infusion of 2.5 g. Tumour vessels with flow spreading into the tumour and/or homogeneously stained hyperechoic images were observed in 34 of the 41 hepatocellular carcinomas (sensitivity, 82.9%; specificity, 93.8%). Peripheral enhancements were characteristic of intrahepatic cholangiocarcinoma and metastatic hepatic tumours (sensitivity, 60.0% and 83.3%; specificity, 65.5% and 76.4%, respectively). Pooling at the periphery or throughout the tumour was apparent only in haemangioma (sensitivity, 76.5%; specificity, 100%). A tortuous feeding artery and spoke-like vascularization were evident only in the two focal nodular hyperplasias. Contrast-enhanced ultrasound using coded harmonic ultrasound imaging and Levovist provided detailed information about tumour vascularity and contrast enhancement patterns in hepatic tumours.

Transcatheter arterial chemoembolization of hepatocellular carcinoma: usefulness of coded phase-inversion harmonic sonography

OBJECTIVE

The purpose of our study was to assess the value of coded phase-inversion harmonic sonography performed approximately 1 week after the patients had undergone transcatheter arterial chemoembolization with iodized oil for hepatocellular carcinoma.

SUBJECTS AND METHODS

We studied 40 patients with 44 nodules measuring 1.5-11.0 cm in diameter (mean +/- SD, 3.9 +/- 2.0 cm) who underwent transcatheter arterial chemoembolization. Coded phase-inversion harmonic sonography, a technique based on a combination of phase-inversion harmonics and coded technology, was performed with a contrast agent approximately 1 week after chemoembolization. The results were compared with those obtained using dynamic CT (n = 44 lesions) and dynamic MR imaging (n = 20 lesions). We also evaluated the recurrence of hepatocellular carcinoma during clinical follow-up in 17 patients who did not undergo additional local therapy.

RESULTS

The detection rates of intratumoral vascularity of coded phase-inversion harmonic sonography, dynamic CT, and dynamic MR imaging were, respectively, 38 (86%) of 44 lesions, 19 (43%) of 44 lesions, and 10 (50%) of 20 lesions. Of 19 nodules of hepatocellular carcinoma treated only by transcatheter arterial chemoembolization, 17 nodules showed enhancement on coded phase-inversion harmonic sonography, suggesting incomplete responses. In all 17 nodules, apparent recurrence was noted on dynamic CT during clinical follow-up, even in nodules that had been observed to be completely filled with iodized oil 1 week after the chemoembolization.

CONCLUSION

We found coded phase-inversion harmonic sonography to be highly sensitive and accurate for evaluating the treatment response in patients with hepatocellular carcinoma even shortly after treatment. Consequently, it allows early recognition of the need for additional local ablation therapy and estimation of the risk of hepatocellular carcinoma recurrence.

Percutaneous ablation therapy guided by contrast-enhanced sonography for patients with hepatocellular carcinoma

OBJECTIVE

The newly developed contrast-enhanced harmonic gray-scale sonography technique enables us to improve the real-time detectability of viable tumor tissue in hepatocellular carcinoma lesions. We evaluated the usefulness of real-time percutaneous ablation therapy under guidance with this method for patients with hepatocellular carcinoma that is not depicted on conventional sonography.

SUBJECTS AND METHODS

We examined 30 patients with 56 hepatocellular carcinomas using real-time contrast-enhanced harmonic gray-scale sonography after injection of a galactose-palmitic acid contrast agent and compared the results with the findings of contrast-enhanced helical CT. We performed percutaneous ablation therapy guided by this modality for treatment of viable hepatocellular carcinoma lesions that could not be detected using conventional sonography.

RESULTS

High detection rates of viable hepatocellular carcinoma lesions were obtained using real-time contrast-enhanced harmonic gray-scale sonography (52/56 lesions, 93%); these rates were comparable to those of helical CT (54/56 lesions, 96%). Nine (90%) of the 10 lesions that were not detected on conventional sonography but were depicted on real-time contrast-enhanced harmonic gray-scale sonography (incomplete local treatment, n = 4; small new lesion, n = 6) were successfully treated with percutaneous ablation therapy guided by this method.

CONCLUSION

Real-time contrast-enhanced harmonic gray-scale sonography improved the sensitivity for the detection of viable hepatocellular carcinoma lesions. Percutaneous ablation therapy guided by this modality may be useful in patients with hypervascular hepatocellular carcinoma lesions that cannot be detected using conventional sonography.

Imaging evaluation of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common causes of cancer death worldwide. Numerous surgical and nonsurgical treatment options are available for treating patients with HCC. Successful long-term outcome is dependent on early detection and accurate delineation of the number and location of tumor nodules. Noninvasive imaging modalities, including ultrasound, computed tomography, magnetic resonance imaging, and positron emission tomography, are commonly used in the initial evaluation of these patients. Herein, the authors present the different manifestations of HCC with these imaging modalities and the role of imaging in the follow-up of patients after nonsurgical treatment.

Contrast-enhanced sonography of small pancreatic mass lesions

OBJECTIVE

To evaluate the usefulness of contrast-enhanced wideband harmonic gray scale sonography in assessing the vascularity of small pancreatic mass lesions.

METHODS

Twenty-five patients with 25 pancreatic mass lesions (20 pancreatic carcinomas, 1 islet cell tumor, 1 malignant lymphoma, and 3 focal inflammatory pancreatic masses due to chronic pancreatitis) were examined. All patients held their breath for 20 to 50 seconds after injection of a contrast agent while the vascularity of the tumor was observed on contrast-enhanced wideband harmonic gray scale sonography (early phase). We then monitored the tumor enhancement 60 to 120 seconds after the injection while the patients held their breath for a few seconds (delayed phase).

RESULTS

All 20 (100%) of the pancreatic carcinomas showed no contrast enhancement in the early phase. Fifteen (75%) of the 20 pancreatic carcinomas also showed no contrast enhancement in the delayed phase. The remaining 5 (25%) pancreatic carcinomas showed mild enhancement in the peripheral regions of the tumor in the delayed phase. The other pancreatic masses showed mild or pronounced enhancement throughout the entire lesions in both the early and delayed phases.

CONCLUSIONS

Contrast-enhanced wideband harmonic gray scale sonography is a useful tool for differentiating pancreatic carcinomas from focal inflammatory pancreatic masses or hypervascular pancreatic tumors.

Essential techniques for successful radio-frequency thermal ablation of malignant hepatic tumors

Radio-frequency thermal ablation is one of the most promising minimally invasive techniques for the treatment of nonresectable hepatic tumors. Essential technical tips to successful radio-frequency ablation therapy were collected from five international experts. They were organized into five categories: understanding the mechanisms and principles of radio-frequency ablation, modulation of tissue physiologic characteristics to increase tumor destruction, strategies of overlapping ablations, strategies to improve ablation according to tumor location, and imaging strategies after ablation to ensure adequate therapy. Established factors for optimal ablation, as well as emerging technical tips, are addressed with illustrations in each section. These essential tips will be very helpful for physicians performing radio-frequency ablation of hepatic tumors.

Management of hepatocellular carcinoma: advances in diagnosis, treatment and prevention

Since the major causes of hepatocellular carcinoma are hepatitis viruses, the difference and similarity of clinical features in relation to the causative virus may indicate that persistent inflammation of the liver is a major role in hepatocellular carcinoma development in both HBV and HCV infection. However, there is a variety of molecular products of virus-inducing mutagenesis, especially in HBV. An advance in the diagnosis of hepatocellular carcinoma is imaging modality to detect hemodynamics of hepatocellular carcinoma with noninvasive methods of ultrasonography and tumor markers. Chemoprevention using synthetic retinoid is another important issue for the prevention of hepatocellular carcinoma development, as well as viral eradication and suppression of inflammation in the liver using interferon and other drugs.