EASL and AASLD recommendations for the diagnosis of HCC to the test of daily practice.

AIMS: To evaluate the diagnostic performance of CT, MRI and CEUS alone and in combination, for the diagnosis of HCC between 10 and 30 mm, in a large population of cirrhotic patients. PATIENTS AND METHODS: In a multicentre prospective trial, 442 patients have been enrolled. Within a month, CEUS, CT and MRI were performed for all patients. A composite algorithm was defined to obtain the more accurate gold standard. RESULTS: A total of 544 nodules in 381 patients have been retained for the performance analysis. Eighty-two percent of the patients were male, mean age was 62 years. For the 10-20 mm nodules (n=342), the sensitivity (Se) and specificity (Sp) for the diagnosis of HCC were, respectively, 70.6% and 83.2% for MRI, 67.9% and 76.8% for CT and 39.6% and 92.9% for CEUS. For the 20-30 mm nodules (n=202), the Se and Sp were, respectively, 72.3% and 89.4% for MRI, 71.6% and 93.6% for CT and 52.9% and 91.5% for CEUS. THE BEST COMBINATION FOR THE 10-20 MM NODULES WAS MRI + CT (SE: 55.1%, SP: 100.0%).: After a first inconclusive technique, CEUS as second image technique allowed the highest specificity with only a slight drop of sensitivity for 10-20 mm nodules and the highest sensitivity and specificity for 20-30 mm nodules. CONCLUSION: This large multicentre study validates the EASL/AASLD recommendations in daily practice. Specificity using CT or MRI in 10-20 mm HCC was low, but we do not recommend combined imaging at first as sensitivity would be very low. The best sequential approach combined MRI and CEUS.

Detection of arterial phase hyperenhancement of small hepatocellular carcinoma with MRI: Comparison between single arterial and multi-arterial phases and between extracellular and hepatospecific contrast agents.

PURPOSE: The purpose of this study was to compare the detection rate of arterial phase hyperenhancement (APHE) in small hepatocellular carcinoma (HCC) between single arterial phase (single-AP) and triple hepatic arterial (triple-AP) phase MRI and between extracellular (ECA) and hepato-specific (HBA) contrast agents. MATERIALS AND METHODS: A total of 109 cirrhotic patients with 136 HCCs from seven centers were included. There were 93 men and 16 women, with a mean age of 64.0 ± 8.9 (standard deviation) years (range: 42-82 years). Each patient underwent both ECA-MRI and HBA (gadoxetic acid)-MRI examination within one month of each other. Each MRI examination was retrospectively reviewed by two readers blinded to the second MRI examination. The sensitivities of triple- and single-AP for the detection of APHE were compared, and each phase of the triple-AP sequence was compared with the other two. RESULTS: No differences in APHE detection were found between single-AP (97.2%; 69/71) and triple-AP (98.5%; 64/65) (P > 0.99) at ECA-MRI. No differences in APHE detection were found between single-AP (93%; 66/71) and triple-AP (100%; 65/65) at HBA-MRI (P = 0.12). Patient age, size of the nodules, use of automatic triggering, type of contrast agent, and type of sequence were not significantly associated with APHE detection. The reader was the single variable significantly associated with APHE detection. For triple-AP, best APHE detection rate was found for early and middle-AP images compared to late-AP images (P = 0.001 and P = 0.003). All APHEs were detected with the combination of early-AP and middle-AP images, except one that was detected on late-AP images by one reader. CONCLUSION: Our study suggests that both single- and triple-AP can be used in liver MRI for the detection of small HCC especially when using ECA. Early AP and middle-AP are the most efficient phases and should be preferred for detecting APHE, regardless of the contrast agent used.

A proposal for a useful algorithm to diagnose small hepatocellular carcinoma on MRI.

OBJECTIVE: To assess MRI features for the diagnosis of small hepatocellular carcinomas (HCCs) and especially for nodules not showing both of the typical hallmarks. PATIENTS AND METHODS: Three hundred and sixty-four cirrhotic patients underwent liver MRI for 10-30 mm nodules suggestive of HCC. The diagnostic performances of MRI features [T1, T2; diffusion-weighted (DW) imaging signal, enhancement, capsule, fat content] were tested, both individually and in association with both typical hallmarks and as substitutions for one hallmark. The diagnostic reference was obtained using a multifactorial algorithm ensuring high specificity (Sp). RESULTS: Four hundred and ninety-three nodules were analyzed. No alternative features, associations or substitutions outperformed the typical hallmarks for the diagnosis of HCC. For 10-20 mm nodules not displaying one of the typical hallmarks, hyperintensity on DW images was the most accurate substitutive sign, providing a sensitivity of 71.4% and Sp of 75% for nodules without arterial enhancement and sensitivity = 65.2% and Sp = 66% for nodules without washout on the portal or delayed phases. A new diagnostic algorithm, including typical hallmarks as a first step then the best-performing substitutive signs (capsule presence or DW hyperintensity) in combination with the nonmissing typical hallmark as a second step, enabled the correct classification of 77.7% of all nodules, regardless of size. CONCLUSION: Using MRI, the typical hallmarks remain the best criteria for the diagnosis of small HCCs. However, by incorporating other MRI features, it is possible to build a simple algorithm enabling the noninvasive diagnosis of HCCs displaying both or only one of the typical hallmarks.