Sensitivity of ultrasound in detecting hepatocellular carcinoma in obese patients compared to explant pathology as the gold standard

Abstract

Background/Aims: The American Association for the Study of Liver Diseases recommends ultrasound (US) screening for hepatocellular carcinoma (HCC) among cirrhotic patients, regardless of body mass index (BMI), every 6 months. We examined US sensitivity for diagnosis of HCC in obese patients. Methods: Liver transplant patients data with HCC in explant was used (January 2012-December 2017). All patients underwent liver US within 3 months of diagnosis of HCC. Number/size of HCC lesions were extracted from radiologic and pathologic reports. Obesity was defined as BMI ≥30 kg/m2. Results: One hundred sixteen patients were included. 80% were male, with mean BMI of 31 kg/m2. The most common underlying liver disease was hepatitis C virus (62%). At the time of diagnosis, median number of HCC lesions was 2 (interquartile range [IQR], 1–3), and median size of the largest lesion was 2.5 cm (IQR, 1.75–3.9). Overall sensitivity of US study for detection of HCC was 33% (95% confidence interval [CI], 29–48%). Sensitivity was 77% (95% CI, 62–93%) in patients with BMI<30 and 21% (95% CI, 11–30%) in patients with BMI≥30 (P<0.001). Size of the largest HCC lesion (P=0.290) and number of lesions (P=0.505) were not different between groups. Computed tomography (CT) scan detected HCC in 98% of the obese patients with negative US. Conclusions: Sensitivity of US for detection of HCC is significantly lower among obese patients compared to overweight and normal weight patients. These patients may benefit from alternating between US and a different imaging modality.