Lack of arterial hypervascularity at contrast-enhanced ultrasound should not define the priority for diagnostic work-up of nodules <2 cm

Background & Aims Current guidelines recommend diagnostic work-up for nodules >1cm detected during screening for hepatocellular carcinoma (HCC). This implies that patients with benign conditions may undergo unnecessary evaluation and those with small nodules may be intervened too early, leading to overdiagnosis. Since increased arterial vascularization is the hallmark of malignancy, its detection by contrast-enhanced ultrasound (CEUS) could become the signal to proceed with diagnosis confirmation. The aim was to assess if HCCs Methods We prospectively included 168 cirrhotic patients with a newly detected solitary nodule of 5–20mm by screening ultrasonography. MRI, CEUS and fine needle biopsy (FNB) were performed and if no confident diagnosis was obtained, patients were closely followed to rule out HCC. Final diagnosis was: HCC (n=119), cholangiocarcinoma (n=3), neuroendocrine tumour (n=1) and benign lesions (n=45). Results CEUS did not detect contrast hyperenhancement in the arterial phase in 55 cases (34%). Eighteen out of these 55 nodules were diagnosed as HCC. Non-CEUS hyperenhanced HCCs were more frequently well-differentiated than CEUS-hyperenhanced HCCs ( p Conclusions Absence of contrast hyperenhancement on CEUS during the arterial phase in nodules