Diagnosis of hepatic neoplasms using CT arterial portography and CT hepatic arteriography

The Added Diagnostic Value of Transcatheter CT Hepatic Arteriography for Intraprocedural Detection of Previously Unknown Colorectal Liver Metastases During Percutaneous Ablation and Impact on the Definitive Treatment Plan

PURPOSE

This study assessed the diagnostic value of CT hepatic arteriography (CTHA) for the intraprocedural detection of previously unknown colorectal liver metastases (CRLM) and the impact on the definitive treatment plan.

MATERIALS AND METHODS

All patients treated with CTHA-guided percutaneous ablation for CRLM between January 2012 and March 2022 were identified from the Amsterdam Colorectal Liver Met Registry (AmCORE). Radiology reports of the ablative procedure and follow-up imaging were reviewed to see if (a) previously unknown CRLM were detected intra-procedurally and if (b) new CRLM, potentially missed on CTHA, appeared within 6 months following the procedure; three abdominal radiologists re-reviewed the baseline CTHA scans of these patients with early recurrence. To ratify immediate ablations of concomitantly detected CRLM, the upper limit of false positives was predefined at 10%.

RESULTS

One hundred and fifty-two patients were included. With CTHA, a total of 17 additional tumours in 15 patients were diagnosed and treated immediately, two representing disappeared tumours following systemic chemotherapy. Compared to the conventional contrast-enhanced (ce)CT, ceMRI and 18F-FDG PET-CT, adding CTHA was superior for the detection of CRLM (P < .001). Within 12 months of follow-up 121, new CRLM appeared in 49/152 patients (32.2%); retrospective blinded assessment revealed 56 to already be visible on the baseline CTHA scan (46%); four lesions without substrate on follow-up scans were considered false positives (n = 4/60; 7%). Arterial ring enhancement was the most frequently reported imaging characteristic (n = 45/60; 75%).

CONCLUSION

The subsequent use of CTHA has added value for the detection of previously unknown and vanished CRLM. Taking into account the low number of false positives (7%) and the favourable safety profile of percutaneous ablation, we believe that immediate ablation of typical ring-enhancing supplementary tumours is justified and sufficiently validated.

LEVEL OF EVIDENCE

Level 3; individual cross-sectional study with consistently applied reference standard and blinding.

The diagnostic value of dual-phase cone-beam CT during hepatic arteriography in transarterial chemoembolization for hepatocellular carcinoma

To evaluate the diagnostic value of dual-phase cone beam CT during hepatic arteriography (CBCTHA) for hepatocellular carcinoma (HCC).Thirty seven patients with unresectable HCC underwent the dual-phase CBCTHA prior to transarterial chemoembolization (TACE). Three blinded observers independently reviewed and compared the first phase CBCTHA images alone and the dual phase CBCTHA images. Diagnostic accuracy was evaluated by the alternative free-response receiver operating characteristic method (Area under the curve: Az value). Sensitivities were analyzed with the paired t test. The analysis was performed for overall HCCs, HCCs up to 1 cm and those larger than 1 cm.For all HCCs and HCCs up to 1 cm, Az value and sensitivity showed no significant difference between the first-phase CBCTHA alone and the dual-phase CBCTHA (Az: 0.81 vs 0.88, P = .07, 0.79 and 0.85, P = .14, sensitivity: 0.61 and 0.73, P = .11, 0.41 and 0.52, P = .33, respectively). For HCCs larger than 1 cm, the mean Az value and sensitivity for the dual-phase CBCTHA were significantly higher than those for the first phase CBCTHA alone (Az: 0.96 vs 0.92, P = .008, sensitivity: 0.85 vs 0.75, P = .013, respectively).The diagnostic accuracy of the dual-phase CBCTHA was superior to that of the first phase CBCTHA alone in the diagnosis of HCC larger than 1 cm.

Treatment of a non-typical hepatic pseudolesion complicated by greatly elevated alpha fetoprotein: case report and literature review

Background

Hepatic pseudolesions detected by helical computed tomography (CT) are not rare, but it is difficult to make a final diagnosis when the hepatic lesion is complicated by the presence of greatly elevated alpha fetoprotein (AFP). Clinical treatment of non-typical hepatic pseudolesions complicated by greatly elevated AFP should confirm the diagnosis and minimize trauma.

Case presentation

Non-invasive procedures including ultrasonography, CT, and micro-invasive digital subtraction angiography could not safely differentiate this lesion from a malignant focus when it was complicated by greatly elevated AFP. Laparoscopic hepatectomy was performed, and pathological analysis showed chronic hepatitis, nodular regenerative hyperplasia, focal nodular hyperplasia of the liver, and mild vascular malformation. The tissue was HbsAg(−), HbcAg(−), and AFP(+).

Conclusion

Heightened awareness of hepatic pseudolesion complicated by primarily elevated AFP will help physicians avoid unnecessary invasive procedures. Hepatic biopsy is inevitable because of greatly elevated AFP. For suspected hepatic pseudolesion with elevated AFP, needle-core biopsy and follow-up surveillance instead of hepatectomy are recommended to find the source of AFP and make a final diagnosis of pseudolesion.

Hypovascular nodules in patients with chronic liver disease: risk factors for development of hypervascular hepatocellular carcinoma

PURPOSE

To identify patient characteristics and magnetic resonance (MR) imaging findings associated with subsequent hypervascularization in hypovascular nodules that show hypointensity on hepatobiliary phase gadoxetic acid-enhanced MR images in patients with chronic liver diseases.

MATERIALS AND METHODS

Institutional review board approval was obtained, and informed consent was waived. At multiple follow-up gadoxetic acid-enhanced MR imaging examinations of 68 patients, 160 hypovascular nodules were retrospectively reviewed. A Cox regression model for hypervascularization was developed to explore the association of baseline characteristics, including patient factors (Child-Pugh classification, etiology of liver disease, history of local therapy for hepatocellular carcinoma [HCC], and coexistence of hypervascular HCC) and MR imaging findings (fat content, signal intensity on T2-weighted images, and nodule size). In addition, the growth rate was calculated as the reciprocal of tumor volume doubling time to investigate its relationship with subsequent hypervascularization by using receiver operating characteristic and Kaplan-Meier analyses.

RESULTS

The prevalence of subsequent hypervascularization was 31% (50 of 160 nodules). Independent Cox multivariable predictors of increased risk of hypervascularization were hyperintensity on T2-weighted images (hazard ratio [HR] = 8.7; 95% confidence interval [CI]: 3.6, 20.8), previous local therapy for hypervascular HCC (HR = 5.0; 95% CI: 1.8, 13.6), Child-Pugh B cirrhosis (HR = 3.6; 95% CI: 1.4, 9.5) and coexistence of hypervascular HCC (HR = 2.0; 95% CI: 1.0, 3.8). The mean growth rate was significantly higher in nodules that showed subsequent hypervascularization than in those without hypervascularization. Kaplan-Meier analysis based on the receiver operating characteristic cutoff level (1.8 × 10(-3)/day [tumor volume doubling time, 542 days]) showed that nodules with a higher growth rate had a significantly higher incidence of hypervascularization (P = 5.2 × 10(-8), log-rank test).

CONCLUSION

Hyperintensity on T2-weighted images is an independent and strong risk factor at baseline for subsequent hypervascularization in hypovascular nodules in patients with chronic liver disease. Tumor volume doubling time of less than 542 days was associated with a high rate of subsequent hypervascularization.

Diagnostic accuracy of C-arm CT during selective transcatheter angiography for hepatocellular carcinoma: comparison with intravenous contrast-enhanced, biphasic, dynamic MDCT

PURPOSE

This study was aimed to compare the accuracy, sensitivity, and positive predictive value of C-arm CT (CACT) during selective transcatheter angiography with those of multidetector CT (MDCT) in the detection of hepatocellular carcinoma (HCC).

MATERIAL AND METHODS

In this prospective study, 30 patients (mean age, 73 years) with unresectable HCC were examined with CACT before chemoembolisation. Images of a combination of CACT during arterial portography (CACTAP) and dual-phase CACT during hepatic arteriography (CACTHA) was obtained and images of intravenous contrast-enhanced, biphasic, dynamic, MDCT was also obtained beforehand. Three blinded observers independently reviewed CACT and MDCT. Diagnostic accuracy was evaluated by the alternative free-response receiver operating characteristic (AFROC) method. Sensitivities and positive predictive values (PPV) were analyzed with the paired t-test.

RESULTS

In the mean area under the AFROC curve (Az), there was no significant difference between MDCT and CACT (MDCT, mean Az value, 0.83; CACT, 0.85, respectively) (P = 0.32). There was also no significant difference between the two techniques in sensitivity (MDCT, mean 0.65; CACT, 0.60) and PPV (MDCT, mean 0.98; CACT, 0.97) (P = 0.40, P = 0.68, respectively).

CONCLUSION

The diagnostic accuracy of CACT was equivalent to that of biphasic CT in the diagnosis of HCC.

KEY POINTS

C-arm CT helps detection of hepatocellular carcinoma (HCC) during interventional (TACE) treatment. C-arm CT for HCC seemed just as accurate as biphasic CT. TACE can be performed with greater confidence using C-arm CT.

Utility of C-arm CT in patients with hepatocellular carcinoma undergoing transhepatic arterial chemoembolization

PURPOSE

To evaluate the utility of C-arm computed tomography (CT) on treatment algorithms in patients undergoing transhepatic arterial chemoembolization for hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

From March 2008 to July 2008, 84 consecutive patients with HCC underwent 100 consecutive transhepatic arterial chemoembolizations with iodized oil. Unenhanced and iodinated contrast medium-enhanced C-arm CT with planar and three-dimensional imaging were performed in addition to conventional digital subtraction angiography (DSA) in all patients. The effect on diagnosis and treatment was determined by testing the hypotheses that C-arm CT, in comparison to DSA, provides (a) improved lesion detection, (b) expedient identification and mapping of arterial supply to a tumor, (c) improved characterization of a lesion to allow confident differentiation of HCC from pseudolesions such as arterioportal shunts, and (d) an improved evaluation of treatment completeness. The effect of C-arm CT was analyzed on the basis of information provided with C-arm CT that was not provided or readily apparent at DSA.

RESULTS

C-arm CT was technically successful in 93 of the 100 procedures (93%). C-arm CT provided information not apparent or discernible at DSA in 30 of the 84 patients (36%) and resulted in a change in diagnosis, treatment planning, or treatment delivery in 24 (28%). The additional information included, amongst others, visualization of additional or angiographically occult tumors in 13 of the 84 patients (15%) and identification of incomplete treatment in six (7.1%).

CONCLUSIONS

C-arm CT is a useful collaborative tool in patients undergoing transhepatic arterial chemoembolization and can affect patient care in more than one-fourth of patients.

CT Scan and MRI in the Differentiation of Liver Tumors

Computed tomography (CT) and magnetic resonance imaging (MRI) are useful for detection and characterization of liver tumors, and widely used in clinical practice. By using dynamic CT and MRI with extracellular contrast material or MRI with liver-specific contrast material, we can investigate the morphological, hemodynamical and functional nature of focal hepatic lesions. Tumors often show characteristic findings on CT and MRI. Thus, we can correctly establish a diagnosis of liver tumors based on those findings. In this article, we describe the role of CT scan and MRI in the differentiation of liver tumors as well as presenting some typical CT and MR images.