P0722 - Limited Ultrasound Visualization Is Associated with Lower Specificity During Hepatocellular Carcinoma Surveillance

Nicolas Chong, MD, Haley Schoenberger, MD, Sruthi Yekkaluri, , David T. Fetzer, MD, Nicole E. Rich, MD, MS, Takeshi Yokoo, MD, Amit G. Singal, MD, MS
University of Texas Southwestern Medical Center, Dallas, TX

Introduction: Approximately 20% of ultrasounds (US) performed for hepatocellular carcinoma (HCC) surveillance in patients with cirrhosis have limited liver visualization; however, it is unknown if this affects US diagnostic performance. We aimed to evaluate the association between US visualization and specificity in a cohort of patients with cirrhosis undergoing US-based surveillance.

Methods: We performed a retrospective cohort study of patients with cirrhosis but without HCC that underwent at least one US exam at two large health systems between 2016 and 2019. All patients were required to undergo a subsequent 4-phase CT or contrast-enhanced MRI within 12 months of the US. For each US, we recorded the LI-RADS visualization score and the presence and size of suspicious masses. Visualization score A was considered adequate, and scores B or C considered limited visualization. US with observations >1cm were considered positive exams. Absence of HCC was confirmed by subsequent CT or MRI exam without any LR-4 (probable HCC), LR-5 (definite HCC), LR-TIV (tumor-in-vein) or LR-M (probable malignancy but not HCC-specific) observations. We performed univariable and multivariable logistic regression, accounting for clustering of multiple US exams within each patient, to evaluate the association between US visualization and specificity.

Results: We identified 2052 patients with cirrhosis undergoing HCC surveillance. Median age of patients was 59.5 years, and 58.1% were male. Most patients (71.9%) had Child Pugh A cirrhosis, and the most common cirrhosis etiologies were hepatitis C (48.4%), alcohol-related (22.2%), and NAFLD (18.0%). Patients underwent a median of 3 (IQR 2 – 4) US during follow-up. Most exams were of adequate visualization, although 24.4% had limited visualization. False positive US results were observed in 89 (4.34%) patients, i.e., specificity of 95.7%. Limited visualization was significantly associated with decreased specificity in univariable (OR 0.71, 95%CI 0.61 – 0.81) and multivariable (OR 0.72, 95%CI 0.64 – 0.83) analysis after adjusting for age, sex, race, cirrhosis etiology, Child Pugh class, and BMI. Cirrhosis etiology and obesity were not associated with specificity in multivariable analysis after adjusting for US visualization.

Discussion: Limited US visualization is associated with decreased specificity and increased risk of screening-related harms, highlighting a need for alternative HCC surveillance modalities in these patients.


Disclosures:


Nicolas Chong, MD, Haley Schoenberger, MD, Sruthi Yekkaluri, , David T. Fetzer, MD, Nicole E. Rich, MD, MS, Takeshi Yokoo, MD, Amit G. Singal, MD, MS. P0722 - Limited Ultrasound Visualization Is Associated with Lower Specificity During Hepatocellular Carcinoma Surveillance, ACG 2021 Annual Scientific Meeting Abstracts. Las Vegas, Nevada: American College of Gastroenterology.