Complete Perilesional Ring on MRI as the indicator of pathological complete response after transarterial therapy for hepatocellular carcinoma

Motivation: Identifying pathological complete response (pCR) nodules in hepatocellular carcinoma (HCC) after transarterial therapy is crucial to avoid unnecessary hepatectomy and retain liver function. Goal(s): To improve the performance in pCR diagnosis beyond current mRECIST method, which has limited precision. Approach: This study integrated complete perilesional ring features (complete hyper- and hypo-rings) on MR with mRECIST to stratify nodules into hyper-ring, hypo-ring, and no-ring categories. Results: The ring classification refined pCR prediction, increasing the precision from 75.0% to 85.4% for hyper-ring nodules, while obtaining a lower pCR probability of 56.1% for the no-ring group, allowing more personalized treatment strategies. Impact: The ring classification provides a more specific pCR probability on the basis of mRECIST, guiding 46.1% nodules with 85.4% pCR possibility to Watch & Wait strategy, and 27.4% nodules with 56.1% pCR possibility to comprehensive treatment by liver surgeon.