Diagnostic per-patient accuracy of an abbreviated hepatobiliary phase gadoxetic acid-enhanced MRI for hepatocellular carcinoma surveillance

Diagnostic per-lesion performance of a simulated gadoxetate disodium-enhanced abbreviated MRI protocol for hepatocellular carcinoma screening

AIM

To evaluate the diagnostic per-lesion performance of a simulated gadoxetate disodium-enhanced abbreviated MRI (AMRI) in cirrhotic and chronic hepatitis B (CHB) patients for hepatocellular carcinoma (HCC) screening.

MATERIALS AND METHODS

Seventy-nine consecutive patients at risk for HCC due to cirrhosis and/or CHB were included in this retrospective study. For each patient, the first gadoxetate disodium-enhanced MRI between 2008 through 2014 was analysed. Two independent readers read an anonymised abbreviated image set comprising axial T1-weighted (W) images with fat saturation in the hepatobiliary phase, 20 minutes or more after gadoxetate injection, and axial T2W single-shot fast spin echo images. Each observation >10 mm was scored as negative or suspicious for HCC. Inter-reader agreement was assessed. A composite reference standard was used to determine the per-lesion diagnostic performance for each reader.

RESULTS

Inter-reader agreement was substantial (κ = 0.75). The final reference standard showed 27 HCCs in 13 patients (median 21 mm, range 11-100 mm). The two readers each correctly scored 23 as suspicious for HCC (sensitivity = 85.2%), scored a total of 27 and 32 observations as suspicious for HCC (positive predictive value [PPV] = 85.2% and 71.9%), and scored 83 and 78 observations or complete examinations as negative for HCC (negative predictive value [NPV] = 95.2% and 94.9%).

CONCLUSIONS

The AMRI protocol provides higher per-lesion sensitivity and NPV than reported values for ultrasound, the current recommended technique for screening, and similar per-lesion sensitivity and PPV to reported values for complete dynamic contrast-enhanced MRI.

Cost-Effectiveness of Risk Score-Stratified Hepatocellular Carcinoma Screening in Patients with Cirrhosis

OBJECTIVES

Hepatocellular carcinoma (HCC) surveillance with biannual ultrasound is currently recommended for all patients with cirrhosis. However, clinical implementation of this "one-size-fits-all" approach is challenging as evidenced by its low application rate. We aimed to evaluate the cost-effectiveness of risk-stratified HCC surveillance strategies in patients with cirrhosis.

METHODS

A Markov decision-analytic modeling was performed to simulate a cohort of 50-year-old subjects with compensated cirrhosis. Risk-stratified HCC surveillance strategies was implemented, in which patients were stratified into high-, intermediate-, or low-risk groups by HCC risk biomarker-based scores and assigned to surveillance modalities tailored to HCC risk (2 non-risk-stratified and 14 risk-stratified strategies) and compared with non-stratified biannual ultrasound.

RESULTS

Quality-adjusted life expectancy gains for biannual ultrasound in all patients and risk-stratified strategies compared with no surveillance were 1.3 and 0.9-2.1 years, respectively. Compared with the current standard of biannual ultrasound in all cirrhosis patients, risk-stratified strategies applying magnetic resonance imaging (MRI) and/or ultrasound only in high- and intermediate-risk patients, without screening in low-risk patients, were cost-effective. Abbreviated MRI (AMRI) for high- and intermediate-risk patients had the lowest incremental cost-effectiveness ratio (ICER) of $2,100 per quality-adjusted life year gained. AMRI in intermediate- and high-risk patients had ICERs <$3,000 across a wide range of HCC incidences.

CONCLUSIONS

Risk-stratified HCC surveillance strategies targeting high- and intermediate-risk patients with cirrhosis are cost-effective and outperform the currently recommended non-stratified biannual ultrasound in all patients with cirrhosis.

Should AFP (or any biomarkers) be used for HCC surveillance?

A PURPOSE OF REVIEW

To address the controversy around the use of biomarkers for hepatocellular carcinoma (HCC) surveillance in individuals with cirrhosis or chronic hepatitis B who are at risk for development of liver cancer.

B RECENT FINDINGS

Recent studies suggest that surveillance for hepatocellular carcinoma is beneficial, even after adjustment for lead time and other biases. Alpha fetoprotein (AFP) is complementary to ultrasound (US) in surveillance, particularly in obese patients and patients with infiltrative tumors. US and AFP are both associated with harms to patients from false positive over-diagnosis, with US appearing to cause greater harms. Including patient demographic characteristics and additional biomarkers into diagnostic models is beneficial. Recent studies emphasize the advantage of time trends in biomarkers over single cross-sectional measurements.

C SUMMARY

AFP and other biomarkers are complementary to US in surveillance for HCC, especially when applied in models including patient variables and incorporating time trends in biomarker levels. With advances in genetic and molecular analysis of tumors, we may be poised at the cusp of a revolution in HCC surveillance.

Tailored algorithms for hepatocellular carcinoma surveillance: Is one-size-fits-all strategy outdated?

PURPOSE OF REVIEW

Current clinical practice guidelines recommend regular hepatocellular carcinoma (HCC) surveillance with biannual ultrasound with or without serum alpha-fetoprotein uniformly applied to all patients with cirrhosis. However, clinical implementation of this one-size-fits-all strategy has been challenging as evidenced by very low application rate below 20% due to various reasons, including suboptimal performance of the surveillance modalities.

RECENT FINDINGS

Newly emerging imaging techniques such as abbreviated MRI (AMRI) and molecular HCC risk biomarkers have increasingly become available for clinical evaluation and implementation. These technologies may have a potential to reshape HCC surveillance by enabling tailored strategies. This would involve performing optimized surveillance tests according to individual HCC risk, and allocating limited medical resources for HCC surveillance based on cost-effectiveness.

SUMMARY

Tailored HCC surveillance could lead to achievement of precision HCC care and substantial improvement of the current dismal patient prognosis.

Whole-body MRI in children: Would a 3D STIR sequence alone be sufficient for investigating common paediatric conditions? A comparative study

OBJECTIVES

To test the performance of a single 3D IR T2-Weighted sequence compared to a Whole-body MRI protocol including DWI, T1-Weighted and STIR 3D IR (3S) in a pediatric population.

METHODS

Two radiologists (15 and 30 years of experience),reviewed WBMRIs: first the STIR alone and 2 weeks later the 3S protocol. The indications were variable. Only positive findings were explicitly reported. A third reader compared the results to gold standard (GS) exams specific for the pathology. Agreement between the two readers, sensitivity and positive predictive value of STIR were calculated.

RESULTS

fifty-four WBMRIs were included (16 suspected child abuse, 8 chronic recurrent multifocal osteomyelitis (CRMO), 11 lymphomas, 4 osteosarcomas, 9 neuroblastomas, 6 histiocytosis). The mean age was 6 years 10 months, range: 1 month to 15 years. Agreement between readers was of 0.87 [0.82-0.91] for 3D STIR, and 0.89 [0.83-0.93] for the 3S protocol. For reader 1 sensitivity of 3D STIR was 81.6% and of 3S 81.0%. For reader 2 it was 74.1% for 3D STIR and 74.7% for 3S. For both readers and for both protocols, the positive predictive value (PPV) depended on the type of disease (for example 100% histocytosis and osteosarcomas, >90% for child abuse, >85% CRMO but <70% for lymphoma and neuroblastoma).

CONCLUSIONS

Sensitivities were not different between the 2 protocols, for each reader and were different between the 2 readers for each protocol.

Combined Application of Gadoxetic Acid Disodium-Enhanced Magnetic Resonance Imaging (MRI) and Diffusion-Weighted Imaging (DWI) in the Diagnosis of Chronic Liver Disease-Induced Hepatocellular Carcinoma: A Meta-Analysis

Objective

Gadoxetic acid disodium (Gd-EOB-DTPA) is a magnetic resonance imaging (MRI) contrast agent to target the liver cells with normal function. In clinical practice, the Gd-EOB-DTPA produces high quality hepatocyte specific image 20 minutes after intravenous injection, so DWI sequence is often performed after the conventional dynamic scanning. However, there are still some disputes about whether DWI sequence will provide more effective diagnostic information in clinical practice. This study aimed to explore the diagnostic value of combining Gd-EOB-DTPA-enhanced MRI and DWI in the detection of hepatocellular carcinoma (HCC) in patients with chronic liver disease.

Methods

A systematic literature search was performed in the PubMed and Cochrane library database up to March 2015. The quality assessment of diagnostic accuracy studies (QUADAS) was used to evaluate the quality of studies. Heterogeneous test on the included literature was performed by using the software Review Manager 5.3. The MetaDiSc 1.4 software was used to calculate the pooled sensitivity, specificity, positive likelihood ratio and negative likelihood ratio; meanwhile the summary receiver operating characteristics (SROC) curve was drawn to compare the diagnostic performance.

Results

A total of 13 literatures were included in this study. In 8 literatures regarding HCC diagnosis based on Gd-EOB-DTPA-enhanced MRI, the pooled sensitivity: 0.90 (95% confidence interval (CI): 0.88–0.93); specificity: 0.89 (95% CI: 0.85–0.92); positive likelihood ratio: 8.60 (95% CI: 6.20–11.92); negative likelihood ratio: 0.10 (95% CI: 0.08–0.14) were obtained. The area under curve (AUC) and Q values were 0.96 and 0.90, respectively. In 5 literatures relating to HCC diagnosis by combination of Gd-EOB-DTPA-enhanced MRI and DWI sequence, the pooled sensitivity: 0.88 (95% CI: 0.85–0.91), specificity: 0.96 (0.94–0.97), positive likelihood ratio: 19.63 (12.77–30.16), negative likelihood ratio: 0.10 (0.07–0.14) were obtained. The AUC value was 0.9833 and Q value was 0.9436. The AUC value of comprehensive evaluation method was significantly higher than that of Gd-EOB-DTPA-enhanced MRI alone(P<0.05).

Conclusion

Combination of Gd-EOB-DTPA-enhanced MRI and DWI sequence significantly improves in both the diagnostic accuracy and specificity of chronic liver disease-associated HCC.