Presenter: Tae-Hyung Kim, MD Seoul, Korea

Presentation: Hepatobiliary Phase Hypointense Nodule without Arterial Phase Hyperenhancement on Gadoxetic Acid-Enhanced MRI: Risk of HCC Intrahepatic Distant Recurrence after Radiofrequency Ablation or Hepatectomy: A Systematic Review and Meta-Analysis; Session: SSC05-02

Author: kf/ktg

Source: RSNA 2019

Last Updated: December 1, 2019

Beware of HBP Hypointense Nodules

A meta-analysis of eight Asian studies focuses on finding markers for the intrahepatic distant recurrence (IDR) risk in patients with treated hepatocellular carcinoma. The patients had undergone either partial hepatectomy or radiofrequency ablation.

Tae-Hyung Kim and his team at Seoul National University Hospital, Korea, identified 423 publications on EMBASE and Pubmed, which had focused on gadoxetic acid and hypovascular/hypointense lesions until April 2019.

After a thorough exclusion process, only eight studies were left in their quantitative synthesis.

  • The oldest study was from 2013, the newest form 2019.
  • Five studies were from Japan, two from Korea, one was from China.
  • The overall patient number was 842.
  • 321 patients (38.1%) showed HBP hypointense nodules without arterial phase hyperenhancement (APHE) – despite their previous treatment.
  • In four studies, partial hepatectomy was the chosen treatment, the other four used radiofrequency ablation (RFA).
  • Two studies included only single preoperative HCC lesions, the other six included multiple lesions.
  • Five studies included lesions >3cm; three only lesions <3cm.
  • One Japanese study (Inoue 2017) did not include hypervascularization of preexisting nodules as IDR; all others did.

These Nodules are a Significant IDR Risk Factor

If HBP hypointense nodules without APHE were present, the overall pooled hazard ratio for intrahepatic distant recurrence was 2.44 (95%-CI: 1.99; 2.98). “This makes these nodules a significant risk factor for intrahepatic distant recurrence after treatment”, said Kim. The hazard ratio was higher for patients after RFA compared to partial hepatectomy, however, this was not statistically significant.

Kim suggests to take these results into account for modifying stratification of patient management.

Asian Population

Session chair Mustafa R. Bashir, Duke University, Durham/NC, USA, asked how the data from an Asian population – that has a lower prevalence of cirrhosis – might translate to patients in the US and Europe. Kim answered that the populations indeed are different and Asian patients tend to get HCC based on hepatitis B or C virus infections. However, as gadolinium-based MRI is reaching EASL guidelines, widespread data will become available in Europe. “We will have to do an additional study about the difference between the two population groups”, said Kim.

Treated HCC patients are at higher risk for intrahepatic distant recurrence, if gadoxetic-enhanced MRI finds nodules that are:  1. Hypointense in the hepatobiliary phase and  2. Do not show hyperenhancement in the arterial phase.