The diagnostic and economic impact of contrast imaging techniques in the diagnosis of small hepatocellular carcinoma in cirrhosis

BACKGROUND: Contrast-enhanced ultrasound (CE-US), contrast CT scan and gadolinium dynamic MRI are recommended for the characterisation of liver nodules detected during surveillance of patients with cirrhosis with US. AIM: To assess the sensitivity, specificity, diagnostic accuracy and economic impact of all possible sequential combinations of contrast imaging techniques in patients with cirrhosis with 1-2 cm liver nodules undergoing US surveillance. PATIENTS/METHODS: 64 patients with 67 de novo liver nodules (55 with a size of 1-2 cm) were consecutively examined by CE-US, CT, MRI, and a fine-needle biopsy (FNB) as diagnostic standard. Undiagnosed nodules were re-biopsied; non-malignant nodules underwent enhanced imaging follow-up. The typical radiological feature of hepatocellular carcinoma (HCC) was arterial phase hypervascularisation followed by portal/venous phase washout. RESULTS: HCC was diagnosed in 44 (66%) nodules (2, <1 cm; 34, 1-2 cm; 8, >2 cm). The sensitivity of CE-US, CT and MRI for 1-2 cm HCC was 26, 44 and 44%, with 100% specificity, the typical vascular pattern of HCC being identified in 22 (65%) by a single technique versus 12 (35%) by at least two techniques carried out at the same time point (p=0.028). Compared with the cheapest dual examination (CE-US+CT), the cheapest single technique of stepwise imaging diagnosis of HCC was equally expensive (euro 26 440 vs euro 28 667), but led to a 23% reduction of FNB procedures (p=0.031). CONCLUSIONS: In patients with cirrhosis with a 1-2 cm nodule detected during surveillance, a single imaging technique showing a typical contrast pattern confidently permits the diagnosis of HCC, thereby reducing the need for FNB examinations.