Meta-analysis: surveillance with ultrasound for early-stage hepatocellular carcinoma in patients with cirrhosis

Background A majority of studies investigating the accuracy of ultrasound for detecting hepatocellular carcinoma (HCC) do not reflect how this test is used for surveillance vs. diagnosis. Aim To determine the performance characteristics of surveillance with ultrasound for the detection of HCC, particularly early HCC as defined by the Milan criteria. Methods A systematic literature review using the MEDLINE and SCOPUS databases yielded six studies that evaluated the accuracy of ultrasound for HCC at any stage and 13 studies that were specific to early HCC. Results Surveillance ultrasound detected the majority of tumours before they presented clinically, with a pooled sensitivity of 94%. However, ultrasound was less effective for detecting early HCC with a sensitivity of 63%. Alpha-fetoprotein provided no additional benefit to ultrasound. Meta-regression analysis demonstrated a significantly higher sensitivity for early HCC with ultrasound every 6 months than with annual surveillance. Current studies have limitations such as verification bias and are of suboptimal quality. Conclusions Surveillance with ultrasound demonstrates limited sensitivity for early HCC, although this may be improved by testing at 6-month intervals. Currently available evidence evaluating surveillance ultrasound has significant limitations and future studies are necessary to determine optimal surveillance methods for early HCC.