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.