Endoscopic ultrasound (EUS) and EUS-guided fine-needle aspiration (FNA) of liver lesions

Background: Endoscopic ultrasonography (EUS) is not traditionally thought to be clinically applicable in liver imaging. EUS-guided fine-needle aspiration of the liver has not been well described. Methods: A prospective study was conducted ire which 574 consecutive patients with a history or suspicion of gastrointestinal or pulmonary malignant tumor undergoing upper EUS examinations underwent EUS evaluation of the liver. Fourteen (2.4%) patients were found to have focal liver lesions and underwent EUS-guided fine-needle aspiration. Results: The median largest diameter of the liver lesions was 1.1 cm (range 0.8 to 5.2 cm). The mean number of passes was 2.0 (range 1 to 5 passes). All fine-needle passes yielded an adequate specimen. One of the 14 patients underwent EUS-guided fine-needle aspiration of 2 liver lesions. Fourteen of the 15 liver lesions sampled by means of EUS-guided fine-needle aspiration were malignant and one was benign. Before EUS, computed tomography (CT) depicted liver lesions in only 3 of 14 (21%) patients. Seven of 14 patients had a known cancer diagnosis. For the other 7, the initial diagnosis of cancer was made by means of EUS-guided fine-needle aspiration of the liver. There were no immediate or late complications. Conclusions: EUS can detect small focal liver lesions that are not detected at CT. Findings of EUS-guided fine-needle aspiration can confirm a cytologic diagnosis of liver metastasis and establish a definitive M stage that may change clinical management.