Natural History of Incidental Enhancing Nodules on Cone-Beam Computed Tomography during Transarterial Therapy of Hepatocellular Carcinoma.

ABSTRACT

PURPOSE: To evaluate the natural history of incidental enhancing nodules (IENs) on contrast-enhanced cone-beam computed tomography (CT) during transarterial treatment of hepatocellular carcinoma (HCC). MATERIAL AND METHODS: A single-center retrospective analysis of 100 patients with HCC who underwent contrast-enhanced cone-beam CT prior to transarterial treatment from August 2015 to June 2019 was performed. Inclusion criteria were patients with segmental distribution sublobar HCC, contrast-enhanced cone-beam CT of the target lesion and nontarget liver parenchyma, and follow-up cross-sectional imaging. Patients with IENs ≥3 mm that did not meet imaging criteria for HCC were analyzed. Exclusion criteria included biphenotypic tumors and IEN present inside the treated area of the liver. RESULTS: Fifty-six patients demonstrated 154 IENs on contrast-enhanced cone-beam CT, of which 13 IENs (8.5%) progressed to HCC. The mean primary tumor size was 29 mm (range 10.2-189 mm). Ten patients had ≥4 IENs, and 46 patients had 1-3 IENs. The mean IEN size was 6.8 mm (range 3.0-16.3 mm). The median follow-up interval after contrast-enhanced cone-beam CT was 282 days (interquartile range 143-522). Increased alpha-fetoprotein before treatment (≥15.5 ng/mL, P = .035), having ≥4 IENs (P = .020), and hepatitis C virus (P = .015) were significantly correlated with IEN progression to HCC. No statistically significant differences were identified in baseline neutrophil-to-lymphocyte ratio, targeted HCC characteristics (size, macrovascular invasion, infiltrative pattern, enhancement pattern, and satellite lesions), and IEN size between those with IEN progression to HCC and those without. CONCLUSIONS: Most IENs of ≥3 mm on contrast-enhanced cone-beam CT in patients with segmental distribution sublobar HCC do not progress to HCC. Patients with segmental distribution sublobar HCC with ≥4 IENs, alpha-fetoprotein elevation (≥15.5 ng/mL), or hepatitis C virus have an increased risk of IEN progression to HCC.