Retrospective analysis of current guidelines for hepatocellular carcinoma diagnosis on gadoxetic acid-enhanced MRI in at-risk patients.

Objective: To evaluate and compare the diagnostic performance of the updated HCC guidelines using gadoxetic acid-enhanced MRI.

Methods: In this study, patients at risk of HCC who underwent gadoxetic acid-enhanced MRI following US/CT surveillance were retrospectively recruited from 3 centers. Three radiologists independently evaluated hepatic nodule imaging features relevant to the diagnostic criteria outlined in each guideline. Per-lesion sensitivity, specificity, and accuracy were compared between guidelines using logistic regression with a generalized estimating equation. Inter-observer agreements on imaging features were determined using Fless κ statistics.

Results: Altogether, 447 nodules (310 HCCs, 20 combined hepatocellular-cholangiocarcinomas, 2 cholangiocarcinomas, and 115 benign entities) measuring 1-3 cm from 386 patients were assessed. The KLCA-NCC and APASL guidelines showed the highest sensitivity (82.3-90.6%, p < .001) and accuracy (83.9-88.6%) among the five guidelines. The OPTN/UNOS guideline showed the highest specificity (94.9-97.1%), followed by the AASLD/LI-RADS, EASL, KLCA-NCC, and APASL guidelines, with significant difference only with the APASL guideline. The diagnostic performance of the updated AASLD/LI-RADS and EASL guidelines and of the KLCA-NCC and APASL guidelines was comparable (p > .05). Inter-observer agreement was substantial to almost perfect (κ = 0.73-0.87).

Conclusions: For the diagnosis of HCC using gadoxetic acid-enhanced MRI, the KLCA-NCC and APASL guidelines showed the highest sensitivity and accuracy. The OPTN/UNOS guideline showed the highest specificity. Acknowledging their relative strengths and weaknesses could help adapt the diagnostic criteria according to the clinical context.

Key Points: • APASL and KLCA-NCC provided significantly the highest sensitivity and accuracy, followed by AASLD/LI-RADS and EASL in an endemic area for hepatitis B. • OPTN/UNOS showed the highest specificity, followed by AASLD/LI-RADS, EASL, KLCA-NCC, and APASL guidelines, with significant difference only with APASL. • Broadened definition of arterial hyperenhancement, washout, and the size of the lesion eligible to apply diagnostic criteria may improve the diagnostic performance for HCC in an endemic area for hepatitis B.