[Computerized tomography with lipiodol in hepatocarcinoma. Assessment of its diagnostic accuracy with...

To assess the diagnostic accuracy and predictive value of Lipiodol CT for hepatocellular carcinoma (HCC) before liver transplantation (OLT).

Seventy-eight cirrhotic patients awaiting OLT underwent Lipiodol CT to demonstrate the presence and extent of possible HCC. Radiologically, focal uptake areas with dense, homogeneous or "mosaic" iodized oil uptake were considered to be neoplastic nodules. All patients underwent OLT within 4 months of Lipiodol CT. Pathologic examination of the explanted livers was performed using the standard technique and, if necessary, with additional slices. Pathologic findings were compared with radiologic results to calculate the diagnostic accuracy and predictive value of Lipiodol CT in relation to both patients and lesions.

Lipiodol CT depicted 61 focal areas of iodized oil uptake in 48 patients; pathologic examinations detected 57 HCC lesions in 42 patients (diameter .8 cm, mean 2.2 cm); agreement with radiologic diagnosis was found in 35 patients only. Patient by patient, Lipiodol CT had 83.3% sensitivity, 63.8% specificity, 74.3% diagnostic accuracy, 72.9% positive predictive value (PPV), and 76.6% negative predictive value. Lesion by lesion, Lipiodol CT showed overall sensitivity and PPV of 75.4-70.5%, 74-69.8% for "small" HCCs (diameter < or = 3 cm), and 72.9-71.1% for nodules < or = 2 cm in size. Eighteen uptake areas in 13 patients were diagnosed as HCC by Lipiodol CT but the finding was not confirmed at histology: 4 were hemangiomas and 14 corresponded to cirrhotic tissue without neoplastic foci.

Our study, as the few others comparing radiologic results and pathologic findings of whole explanted liver, demonstrates that Lipiodol CT has relatively low diagnostic accuracy; particularly, specificity and PPV were limited by possible false positives, with HCC overstaging and mistakes in the indications/contraindications for OLT.