Detection Of Small Hepatocellular Carcinoma Research Articles

Early detection of hypervascularization in hepatocellular carcinoma (≤2 cm) on hepatic arterial phase with virtual monochromatic imaging: Comparison with low-tube voltage CT.

This study aims to assess the diagnostic value of virtual monochromatic image (VMI) at low keV energy for early detection of small hepatocellular carcinoma (HCC) in hepatic arterial phase compared with low-tube voltage (80 kVp) CT generated from dual-energy CT (DE-CT). A total of 107 patients with 114 hypervascular HCCs (≤2 cm) underwent DE-CT, 140 kVp, blended 120 kVp, and 80 kVp images were generated, as well as 40 and 50 keV. CT numbers of HCCs and the standard deviation as image noise on psoas muscle were measured. The contrast-to-noise ratios (CNR) of HCC were compared among all techniques. Overall image quality and sensitivity for detecting HCC hypervascularity were qualitatively assessed by three readers. The mean CT numbers, CNR, and image noise were highest at 40 keV followed by 50 keV, 80 kVp, blended 120 kVp, and 140 kVp. Significant differences were found in all evaluating endpoints except for mean image noise of 50 keV and 80 kVp. Image quality of 40 keV was the lowest, but still it was considered acceptable for diagnostic purposes. The mean sensitivity for detecting lesion hypervascularity with 40 keV (92%) and 50 keV (84%) was higher than those with 80 kVp (56%). Low keV energy images were superior to 80 kVp in detecting hypervascularization of early HCC.

Feasibility of automatic detection of small hepatocellular carcinoma (≤2 cm) in cirrhotic liver based on pattern matching and deep learning

Background and objective. Early detection of hepatocellular carcinoma (HCC) is crucial for clinical management. Current studies have reported large HCC detections using automatic algorithms, but there is a lack of research on automatic detection of small HCCs (sHCCs). This study is to investigate the feasibility of automatic detection of sHCC (≤2 cm) based on pattern matching and deep learning (PM-DL) model. Materials and methods. A retrospective study included 5376 image sets from 56 cirrhosis patients (28 sHCC patients with 32 pathologically confirmed lesions and 28 non-HCC cirrhosis patients) in the training-validation cohort to build and validate the model through five-fold cross-validation. In addition, an external test cohort including 6144 image sets from 64 cirrhosis patients (32 sHCC patients with 38 lesions and 32 non-HCC cirrhosis patients) was applied to further verify the generalization ability of the model. The proposed PM-DL model consisted of three main steps: 3D co-registration and liver segmentation, screening of suspicious lesions on diffusion-weighted imaging images based on pattern matching algorithm, and identification/segmentation of sHCC lesions on dynamic contrast-enhanced images with convolutional neural network. Results. The PM-DL model achieved a sensitivity of 89.74% and a positive predictive value of 85.00% in the external test cohort for per-lesion analysis. No significant difference was observed in volumes (P = 0.13) and the largest sizes (P = 0.89) between manually delineated and segmented lesions. The DICE coefficient reached 0.77 ± 0.16. Similar performances were identified in the validation cohort. Moreover, the PM-DL model outperformed Liver Imaging Reporting and Data System (LI-RADS) in sensitivity (probable HCCs: LR-5 or LR-4, P = 0.18; definite HCCs: LR-5, P < 0.001), with a similar high specificity for per-patient analysis. Conclusion. The PM-DL model may be feasible for accurate automatic detection of sHCC in cirrhotic liver.

Clinical and contrast-enhanced image features in the prediction model for the detection of small hepatocellular carcinomas.

Purpose: To identify novel radiological features and clinical characteristics to improve diagnostic criteria for early detection of small hepatocellular carcinoma (HCC).Patients and Methods: We retrospectively recruited asymptomatic patients with no history of HCC but a high risk of HCC in whom a new, solitary, well-defined, solid nodule between 10 and 20 mm was detected through a screening ultrasound. We retrospectively collected all clinical data, and patients were examined using dynamic contrast-enhanced computed tomography or magnetic resonance imaging; subsequently, fine-needle biopsy was performed. A multivariate analysis of the predictors of small HCCs was performed by fitting a multiple logistic regression model with the stepwise variable selection method.Results: In total, 392 and 347 patients with a small liver nodule received a final pathologic confirmation of HCC and non-HCC, respectively. The estimated odds ratios and 95% confidence intervals of tumor size > 12.45 mm, age > 56.61 years, liver cirrhosis, hepatitis C virus (HCV) carrier status, ln alpha-fetoprotein (AFP) > 1.954, arterial phase enhancement, and portal or venous phase washout appearance without arterial phase enhancement were 2.0735 (1.4746-2.9155), 1.8878 (1.2949-2.7521), 1.6927 (1.1294-2.5369), 1.6186 (1.0347-2.5321), 2.0297 (1.3342-3.0876), 3.7451 (2.3845-5.8821), and 2.0327 (1.3500-3.0608), respectively. The area under the receiver operating characteristic curves for the diagnosis of small HCCs was 0.79 for arterial phase enhancement and 0.75 for portal or venous phase washout appearance without arterial phase enhancement.Conclusion: Clinical and contrast-enhanced image features are valuable in the prediction model for the detection and early diagnosis of small HCCs in patients with a high risk of HCC. In addition to negative portal or venous washout and negative arterial enhancement in images, age > 56.61 years, tumor size > 12.45 mm, HCV carrier status, and ln(AFP) > 1.954, are useful indicators for the early detection of small HCCs.

Combining the Arterial Phase of Contrast-Enhanced Ultrasonography, Gadoxetic Acid-Enhanced Magnetic Resonance Imaging and Diffusion-Weighted Imaging in the Diagnosis of Hepatic Nodules ≤20 mm in Patients with Cirrhosis

Contrast-enhanced ultrasonography (CEUS) and gadoxetic acid-enhanced magnetic resonance imaging (EOB-MRI) were compared with respect to diagnostic efficacy in the detection of small hepatocellular carcinoma. A new diagnostic strategy that combines the arterial phase of CEUS, the hepatobiliary phase of EOB-MRI and diffusion-weighted MR imaging (DWI) is described. One hundred sixteen nodules were enrolled to validate the performance of the strategy. For lesions ≤20 mm in size, the areas under the receiver operating characteristic curves (Az) of CEUS and EOB-MRI were 0.930 (95% confidence interval [CI]: 0.867–0.969) and 0.920 (95% CI: 0.855–0.962) (p = 0.796), respectively. The Az value of the new diagnostic strategy was 0.985 (95% CI: 0.942–0.999) (vs. CEUS, p = 0.026; vs. EOB-MRI, p = 0.014). The sensitivity, specificity and diagnostic accuracy of the new strategy were 95.5% (95% CI: 88.9%–98.8%), 96.3% (95% CI: 81.0%–99.9%) and 95.7% (95% CI: 91.9%–99.4%), respectively. The new diagnostic strategy based on the arterial phase of CEUS, hepatobiliary phase of EOB-MRI and DWI represents an appealing solution for distinguishing small hepatocellular carcinomas from benign lesions, especially when the nodules present atypical enhancement patterns.

Gadoxetic acid-enhanced magnetic resonance imaging for the detection of small hepatocellular carcinoma (≤ 2.0 cm) in patients with chronic liver disease: A meta-analysis

Gadoxetic acid-enhanced magnetic resonance imaging for the detection of small hepatocellular carcinoma (≤ 2.0 cm) in patients with chronic liver disease: A meta-analysis

The Diagnostic Performance of Dynamic Contrast-enhanced MR Imaging for Detection of Small Hepatocellular Carcinoma Measuring Up to 2 cm: A Meta-Analysis.

To determine the performance of dynamic contrast material-enhanced magnetic resonance (MR) imaging in the diagnosis of small (≤2-cm) hepatocellular carcinoma (HCC) and to identify factors that influence this performance. Medline and Embase databases were searched for studies performed from January 2000 to March 2014 in which the performance of MR imaging was reported for the detection of HCC up to 2 cm on either a lesion- or patient-based level, with sufficient data to construct 2 × 2 contingency tables. Diagnostic performance was quantitatively pooled for all studies by using a bivariate random-effects model with exploration involving subgroup analysis, meta-regression, and determination of study heterogeneity. Twenty-two studies with 1387 small HCC lesions in 1908 patients met inclusion criteria. Heterogeneity was higher for sensitivity (range, 30%-99%) than specificity (range, 61%-100%). Overall sensitivity was 78% (95% confidence interval [CI]: 68%, 85%; I(2) = 89%), and overall specificity was 92% (95% CI: 88%, 95%; I(2) = 69%). The primary potential source of bias was use of explant as the reference standard in only 13% of studies, although lower sensitivity in such studies was not significant (59% vs 80%, P = .165). Sensitivities were significantly higher for studies that originated from Asia compared with those that originated elsewhere (89% vs 71%, P = .028), those performed with hepatobiliary phase imaging compared with those without (87% vs 65%, respectively; P = .004), and those in which gadoxetate disodium was used versus an extracellular agent (92% vs 67%, P ≤ .001). Specificity was not significantly different between subgroups (P ≥ .122). At pairwise meta-regression analysis with either study origin from Asia or performance of hepatobiliary phase imaging, only gadoxetate disodium contrast agent showed significant independent association with higher sensitivity (P = .002-.007). Results of this meta-analysis suggest that dynamic contrast-enhanced MR imaging has moderate sensitivity and excellent specificity in the detection of HCC up to 2 cm. Gadoxetate disodium contrast agent showed the strongest association with increased sensitivity.

Detection of small hepatocellular carcinoma using gadoxetic acid‐enhanced MRI: Is the addition of diffusion‐weighted MRI at 3.0T beneficial?

To determine whether adding diffusion-weighted imaging (DWI) to gadoxetic acid-enhanced 3.0T magnetic resonance imaging (MRI) can improve the detection of hepatocellular carcinoma (HCC), particularly for small lesions (≤2 cm) in patients with liver cirrhosis. Data of patients diagnosed with focal liver lesions who had undergone gadoxetic acid-enhanced 3.0T MRI and DWI were retrospectively reviewed. Two radiologists (the observers) reviewed independently MRI images in two reading sessions, that is, gadoxetic acid-enhanced images alone and the combination of DWI (b values: 0 and 600 s/mm(2) ) and gadoxetic acid-enhanced images. They assigned to each lesion a confidence level based on a five-point scale. The area under the receiver operating characteristic curve (AUROC), sensitivity and positive predictive value (PPV) for the detection of HCC were calculated. Both observers found the AUROC of the gadoxetic acid-enhanced images was slightly higher than that of the combined DWI and gadoxetic acid-enhanced MRI images in the detection of HCC (observer 1: 0.947 ± 0.030 vs 0.896 ± 0.042, Z = 1.478, P = 0.139; observer 2: 0.917 ± 0.038 vs 0.868 ± 0.048, Z = 1.296, P = 0.195). The sensitivity for the gadoxetic acid set alone was slightly higher than that for the combined set for observer 1 (97% vs 84%) and slightly lower for observer 2 (74% vs 82%). The PPVs were slightly higher for the gadoxetic acid set alone than for the combined set for both observers (observer 1, 89% vs 80%; observer 2, 93% vs 78%); however, none of the differences were statistically significant (P > 0.05). There is no benefit in adding DWI to gadoxetic acid-enhanced MRI for the detection of HCC at 3.0T.

Detection of small (≤2 cm) HCC in cirrhotic patients: added value of diffusion MR-imaging

To evaluate the usefulness of the diffusion-weighted sequence in the detection of small (≤2 cm) hepatocellular carcinoma (HCC) in patients with cirrhosis. Seventy cirrhotic patients with 93 HCCs underwent MR-Imaging at 1.5 T. MR acquisitions comprised unenhanced T1- and T2-weighted images and post-contrast Gd-BOPTA-enhanced T1W GRE-3D images acquired after approximately 25, 60, 180 s (dynamic phases) and 90 min (hepatobiliary phase). DWI was performed by a SSEPI sequence (b values 0, 50, 400, 800 s/mm(2)). Quantitative analysis was performed to establish significant difference of ADC values of benign lesions compared with that of HCC. Sensitivity, specificity, positive and negative predictive values and diagnostic accuracy of two different protocols with and without diffusion MRI sequence were also calculated and compared each other. A good inverse correlation was found between reference standard and ADC values (ρ = -0.688). The mean ADC value of HCC was significantly lower than the mean value of benign focal liver lesions (p < 0.0001). No significant difference was reported in term of sensitivity, specificity, PPV, NPV and diagnostic accuracy between the two datasets. A trend to a better sensitivity was found when DWI images were considered. The adjunction of DWI does not significantly improve the diagnostic accuracy in the detection of small HCC.

Small Hepatocellular Carcinomas: Improved Sensitivity by Combining Gadoxetic Acid–enhanced and Diffusion-weighted MR Imaging Patterns

To determine if the combination of gadoxetic acid-enhanced magnetic resonance (MR) imaging and diffusion-weighted (DW) imaging helps to increase accuracy and sensitivity in the diagnosis of small hepatocellular carcinomas (HCCs) compared with those achieved by using each MR imaging technique alone. The institutional review board approved this retrospective study and waived the requirement for informed consent. The study included 130 patients (95 men, 35 women) with 179 surgically confirmed small HCCs (≤2.0 cm) and 130 patients with cirrhosis (90 men, 40 women) without HCC who underwent gadoxetic acid-enhanced MR imaging and DW imaging at 3.0 T between May 2009 and July 2010. Three sets of images were analyzed independently by three observers to detect HCC: a gadoxetic acid set (unenhanced, early dynamic, and hepatobiliary phases), a DW imaging set, and a combined set. Data were analyzed by using alternative-free response receiver operating characteristic analysis. Diagnostic accuracy (area under the receiver operating characteristic curve [A(z)]), sensitivity, specificity, and positive predictive value were calculated. The mean A(z) values for the combined set (0.952) were significantly higher than those for the gadoxetic acid set (A(z) = 0.902) or the DW imaging set alone (A(z) = 0.871) (P ≤ .008). On a per-lesion basis, observers showed higher sensitivity in their analyses of the combined set (range, 91.1%-93.3% [163-167 of 179]) than in those of the gadoxetic acid set (range, 80.5%-82.1% [144-147 of 179]) or the DW imaging set alone (range, 77.7%-79.9% [139-143 of 179]) (P ≤ .003). Positive predictive values and specificity for all observers were equivalent for the three imaging sets. The combination of gadoxetic acid-enhanced MR imaging and DW imaging yielded better diagnostic accuracy and sensitivity in the detection of small HCCs than each MR imaging technique alone.

Spectral CT in patients with small HCC: investigation of image quality and diagnostic accuracy

To assess image quality and diagnostic accuracy of monochromatic imaging from spectral CT in patients with small HCC (≤3cm). Twenty-seven patients with 31 HCC underwent spectral CT to generate conventional 140-kVp polychromatic images (group A) and monochromatic images with energy levels from 40 to 140keV (group B) during the late arterial phase (LAP) and the portal venous phase (PVP). Two-sample t tests compared the tumour-to-liver contrast-to-noise ratio (CNR) and mean image noise. Lesion detection for LAP, reader confidence and readers' subjective evaluations of image quality were recorded. Highest CNRs in group B were distributed at 40, 50 and 70keV. Higher CNR values and lesion conspicuity scores (LCS) were obtained in group B than in group A (CNR 3.36 ± 2.07 vs. 1.47 ± 0.89 in LAP; 2.29 ± 2.26 vs. 1.58 ± 1.75 in PVP; LCS 2.82, 2.84, 2.63 and 2.53 at 40-70keV, respectively, vs. 1.95) (P < 0.001). Lowest image noise for group B was at 70keV, resulting in higher image quality than that in group A (4.70 vs. 4.07; P < 0.001). Monochromatic energy levels of 40-70keV can increase detectability in small HCC and this increase might not result in image quality degradation. • Spectral computed tomography may help the detection of small hepatocellular carcinoma. • Monochromatic energy levels of 40-70keV increase the sensitivity for detection. • Prospective study showed that monochromatic imaging provides greater diagnostic confidence. • Monochromatic energy level of 70keV improves the overall image quality.

Ultrasonographic surveillance of hepatocellular carcinoma in cirrhosis: A randomized trial comparing 3- and 6-month periodicities

Detection of small hepatocellular carcinoma (HCC) eligible for curative treatment is increased by surveillance, but its optimal periodicity is still debated. Thus, this randomized trial compared two ultrasonographic (US) periodicities: 3 months versus 6 months. A multicenter randomized trial was conducted in France and Belgium (43 sites). Patients with histologically proven compensated cirrhosis were randomized into two groups: US every 6 months (Gr6M) or 3 months (Gr3M). For each focal lesion detected, diagnostic procedures were performed according to European Association for the Study of the Liver guidelines. Cumulative incidence of events was estimated, then compared using Gray's test. The prevalence of HCC ≤30 mm in diameter was the main endpoint. A sample size of 1,200 patients was required. A total of 1,278 patients were randomized (Gr3M, n = 640; Gr6M, n = 638; alcohol 39.2%, hepatitis C virus 44.1%, hepatitis B virus 12.5%). At least one focal lesion was detected in 358 patients (28%) but HCC was confirmed in only 123 (9.6%) (uninodular 58.5%, ≤30 mm in diameter 74%). Focal-lesion incidence was not different between Gr3M and Gr6M groups (2-year estimates, 20.4% versus 13.2%, P = 0.067) but incidence of lesions ≤10 mm was increased (41% in Gr3M versus 28% in Gr6M, P = 0.002). No difference in either HCC incidence (P = 0.13) or in prevalence of tumors ≤30 mm in diameter (79% versus 70%, P = 0.30) was observed between the randomized groups. US surveillance, performed every 3 months, detects more small focal lesions than US every 6 months, but does not improve detection of small HCC, probably because of limitations in recall procedures.

Characteristics and prognosis of patients with hepatocellular carcinoma after the year 2000 in Japan

The survival rate of patients with hepatocellular carcinoma (HCC) improved through the 1990s in Japan, primarily due to advances in the detection of small HCC under the establishment of surveillance systems. We investigated how the characteristics of patients with HCC changed and whether this trend is continuing after the year 2000. The characteristics and survival rates of patients with initial HCC (not a recurrence) who were diagnosed after the year 2000 until 2008 were analyzed and compared with those of patients in whom HCC was diagnosed in the 1990s or before. In comparison to 8 years before the year 2000, the percentage of patients with better liver function at diagnosis of HCC increased after the year 2000, whereas the size of maximal HCC tumors did not change in comparison to patients before the year 2000. The survival rate of patients continued increasing after the year 2000. The prognosis of patients with HCC continues to improve after the year 2000. This is not due to further improvements in the detection of small-sized HCC; the detection of small HCC had reached a plateau in the 1990s. Rather, this improvement appears to be due in part from the continued increase in the distribution of patients with better liver function at diagnosis.

Detection of Small Hepatocellular Carcinoma: Intraindividual Comparison of Gadoxetic Acid-Enhanced MRI at 3.0 and 1.5 T: Erratum

Detection of Small Hepatocellular Carcinoma: Intraindividual Comparison of Gadoxetic Acid-Enhanced MRI at 3.0 and 1.5 T: Erratum

Tumor size as a prognostic factor in resected small hepatocellular carcinoma: A controversy revisited

The widespread use of screening programs has resulted in an increase in detection of small hepatocellular carcinoma (HCC). Surgical resection generally leads to favorable outcomes in this group of patients; however, the prognostic significance of tumor size and the optimal cutoff point in resected specimens of small HCC have not been well defined. The aim of current study is to evaluate the prognostic significance of tumor size in small resected HCC. Patients who underwent surgical resection for small HCC at the Changhua Christian Hospital during January 2001 to June 2007 were enrolled. Small HCC was defined as a single HCC nodule with maximum diameter ≤ 5 cm. Cox regression hazard ratios for cancer-specific death were calculated to survey the prognostic significance of tumor size. We then determined the optimal cut-point for tumor size that could be used to stratify patients into 5-year disease-free survival (DFS) and cancer-specific survival (CSS) groups. A total of 140 patients who underwent resection of small HCC were enrolled. The mean tumor size was 2.9 cm (range 0.9-5.0) and the mean follow-up period was 43.4 months. The 5-year DFS and CSS rates were 46.6% and 81.6%, respectively. Cox regression analysis revealed that tumor size (hazard ratio = 2.973, 95% confidence interval: 1.073-8.239, P = 0.036) was an independent prognostic factor. Our analysis showed that a tumor size of 3 cm was the cut-point that could dichotomize patients into statistically different 5-year DFS and CSS risk groups. Tumor size is an independent prognostic factor in resected small HCC and the prognostic significance of tumor size may vary according to different cut-off points.

Abstract No. 280: Detection of small hepatocellular carcinoma during transarterial chemoembolization: Comparison between C-arm CT and digital subtraction angiography

Abstract No. 280: Detection of small hepatocellular carcinoma during transarterial chemoembolization: Comparison between C-arm CT and digital subtraction angiography

Effectiveness of temporal and dynamic subtraction images of the liver for detection of small HCC on abdominal CT images: comparison of 3D nonlinear image-warping and 3D global-matching techniques

Misregistration errors occur at the periphery of the hepatic region due to respiratory- and interval-related changes in hepatic shape. To reduce these misregistration errors, we developed a temporal and dynamic subtraction technique to enhance small hepatocellular carcinoma (HCC) by using a 3D nonlinear image-warping technique. The study population consisted of 21 patients with HCC. We registered the present and previous arterial-phase CT images or the present nonenhanced and arterial-phase CT images obtained in the same position by 3D global-matching plus 3D nonlinear image-warping. Temporal subtraction images were obtained by subtraction of the previous arterial-phase CT image from the warped present arterial-phase CT image. Dynamic subtraction images were obtained by subtraction of the present nonenhanced CT image from the warped present arterial-phase CT image. When we used this new technique, the number of good or excellent cases increased from 14.2% (3/21 cases) to 71.4% (15/21 cases) on temporal subtraction images. With this technique, subjective rating scores for image quality improved in 57.1% of cases (12/21 cases) on temporal subtraction images and 81.0% of cases (17/21 cases) on dynamic subtraction images. The results indicated that the new subtraction images were greatly improved by use of the 3D nonlinear image-warping technique.

Detection of Small Hepatocellular Carcinoma

To investigate whether gadoxetic acid-enhanced magnetic resonance imaging (MRI) has the diagnostic capability and sensitivity comparable to the combination of gadopentetate dimeglumine-enhanced MRI and superparamagnetic iron oxide-enhanced MRI (double-contrast MRI) in the detection of small hepatocellular carcinomas (HCCs). Forty-one patients with 56 HCCs (size range, 0.5-2.0 cm) who underwent gadoxetic acid-enhanced MRI and double-contrast MRI with a mean interval of 4 days (range, 3-9 days) were included in this study. HCCs were diagnosed by histology (n = 25) and imaging findings (n = 31). Two observers independently reviewed the gadoxetic acid set (unenhanced, early dynamic, and hepatocyte phase images) and the double-contrast MRI set, at an initial reading session, and then reached consensus. Diagnostic accuracy and sensitivity were evaluated using the alternative-free response receiver operator characteristic method. Diagnostic accuracy (AZ) and sensitivity were similar for both image sets (0.955, 83.9% for gadoxetic acid set; 0.952, 80.4% for double-contrast MRI set) (P > 0.05). There were 5 and 3 HCCs that were verified only on the gadoxetic acid set and double-contrast MRI set, respectively. All 9 HCCs that were not verified on the gadoxetic acid set were assigned a low confidence rating of 1 or 2. However, 3 of the 11 HCCs, which were not verified on double-contrast MRI, were not seen even upon retrospective review. Gadoxetic acid-enhanced MRI can replace double-contrast MRI for the detection of HCCs. Because all HCCs were delineated on gadoxetic acid-enhanced MRI, even with a low confidence rating, and 3 HCCs were not seen on double-contrast MRI, gadoxetic acid-enhanced MRI could be more advantageous than double-contrast MRI for HCC work-up.

Diagnostic efficacy of gadoxetic acid-enhanced MRI in the detection of hepatocellular carcinomas: comparison with gadopentetate dimeglumine

This study compared the efficacy of gadoxetic acid-enhanced MRI and gadopentetate dimeglumine-enhanced MRI in the detection of small hepatocellular carcinoma (HCC). Both MRI techniques were performed on 43 patients with a total of 59 HCCs (size range, 0.5-2.0 cm), with a mean interval between the two MRI studies of 3 days (range, 2-7 days). Two observers reviewed both data sets in consensus. Diagnostic accuracy and sensitivity were evaluated using the alternative-free response receiver operator characteristic (ROC) method. The gadoxetic acid set showed a trend toward increased area under the ROC curve (Az value = 0.958) compared with the gadopentetate dimeglumine set (Az value = 0.927), but the difference was not significant (p = 0.362). The sensitivity of the gadoxetic acid set (n = 51, 86.4%) was significantly higher than that of the gadopentetate dimeglumine set (n = 38, 64.4%) (p = 0.0001). Gadoxetic acid-enhanced MRI is a more sensitive diagnostic tool for detection of HCC than gadopentetate dimeglumine-enhanced MRI.

Comparison of Diffusion-Weighted with T2-weighted Imaging for Detection of Small Hepatocellular Carcinoma in Cirrhosis: Preliminary Quantitative Study at 3-T

To compare diffusion-weighted (DW) with standard T2-weighted imaging for quantitative evaluation of small hepatocellular carcinoma (HCC) in cirrhosis. Fourteen patients (all men; mean age, 58.6 years; age range, 45-69 years) with 22 small HCCs (<3 cm and >1 cm in diameter) in cirrhosis were included in the study. DW imaging with breath-hold single-shot echo planar imaging (b = 0, 800 seconds/mm(2)) and T2-weighted imaging with respiratory triggering fat-suppressed fast spin-echo sequence were performed on a 3-T magnetic resonance unit using an eight-channel torso phased-array coil. The signal intensity (SI) of HCC and liver were measured at workstation. Contrast-to-noise ratio (CNR), contrast ratio (CR, SI(lesion)/SI(liver)), and apparent diffusion coefficient (ADC) values were calculated. CNRs and CRs obtained with DW and T2-weighted images, and ADCs of HCC and liver were compared using nonparametric tests. Two lesions were excluded because of artifacts on DW images. Thus 20 lesions were analyzed. The CNRs obtained with T2-weighted images (27.12 + or - 21.12) were significantly higher (P = .02) than those with DW images (17.52 + or - 13.50). There were no significant difference between the CRs obtained with T2-weighted images (1.83 + or - 0.56) and DW images (2.01 + or - 0.67). There were no significant difference between the mean ADCs of HCC (1.22 x 10(-3) mm(2)/second + or - 0.24) and the cirrhotic liver (1.17 x 10(-3) mm(2)/second + or - 0.17), either. DW imaging with high b value was not superior to standard T2-weighted imaging in terms of lesion conspicuity of small HCC in cirrhosis.

Added value of breathhold diffusion‐weighted MRI in detection of small hepatocellular carcinoma lesions compared with dynamic contrast‐enhanced MRI alone using receiver operating characteristic curve analysis

To evaluate the added value of single-breathhold diffusion-weighted MRI (DWI) in detection of small hepatocellular carcinoma (HCC) lesions (< or =2 cm) in patients with chronic liver disease, by comparing the detection sensitivity of combined DWI/conventional dynamic contrast-enhanced (DCE)-MRI to that of conventional DCE-MRI alone. A total of 37 patients with chronic liver diseases underwent abdominal MRI at 1.5T, including T1-weighted imaging (T1WI), T2-weighted imaging (T2WI), and 2D conventional DCE. For each patient study, axial DWI was performed with a single-shot echo-planar imaging (EPI) sequence using a modified sensitivity-encoding (mSENSE) technique with b-value of 500 seconds/mm(2). A total of 20-24 slices were obtained during a 15-17-second breathhold. Two observers independently interpreted the combined DWI/conventional DCE-MRI images and the conventional DCE-MRI images alone in random order. For all small HCC lesions, the diagnostic performance using each imaging set was evaluated by receiver operating characteristic (ROC) curve analysis. Sensitivity and positive predictive values were also calculated and analyzed. A total of 47 small HCCs were confirmed as final result. The area under the ROC curve (Az) of combined DWI/conventional DCE-MRI images (observer 1, 0.922; observer 2, 0.918) were statistically higher than those of conventional DCE-MRI alone (observer 1, 0.809; observer 2, 0.778) for all small HCC lesions (P < 0.01). The lesion detection sensitivities using the combined technique for both observers were significantly higher than those using conventional DCE-MRI alone (P < 0.01). The sensitivity values for two observers using the combined technique were 97.87% and those using conventional DCE-MRI alone were 85.11% to 82.98%. The positive predictive values for two observers using the combined imaging technique (97.87%) were slightly higher than those using conventional DCE-MRI alone (92.86-93.02%), but there was no significant difference between the two imaging sets. Combined use of breathhold DWI with conventional DCE-MRI helped to provide higher sensitivities than conventional DCE-MRI alone in the detection of small HCC lesions in patients with chronic liver disease.