Aim: To assess the diagnostic performance of Contrast Enhanced Ultrasound (CEUS) for focal liver lesions in a large monocentric study.
Methods: In a retrospective study performed in the Gastroenterology and Hepatology Department, Timișoara, between 09.2009-12.2012, we characterized 504 FLLs (mean diameter 4.5±2.9 cm) in 427 patients (mean age 59.6±12 years, 246 males, 181 females) through CEUS. In each patient a
reference method was available: either contrast enhanced computed tomography (CE-CT), or contrast enhanced magnetic resonance imaging (CE-MRI) or biopsy. A CEUS examination was considered conclusive if the FLL respected the typical enhancement pattern described in the European Federation of Societies for Ultrasound in Medicine and Biology (EFSUMB) guidelines regarding CEUS.
Results: We evaluated 195 (38.7%) FLLs in patients with chronic hepatopathies, and 309 (61.3%) in patients without known liver disease. From all 504 FLLs, CEUS established the malignant or benign character of a lesion in 454 (90.1%) cases.
Of these, 180 (37.5%) were benign, and 274 (54.4%) presented "wash-out" in the late phase (being labeled as malignant). In 50 (8.1%) cases, CEUS was inconclusive, the final diagnosis being made using reference methods. Using “gold-standard” methods, 192 (38.1%) were diagnosed as benign lesions, the other 312 (61.9%) as malignant lesions. CEUS sensitivity, specificity and accuracy for differentiation between benign and malignant lesions were 0.83, 0.86 and 0.85 respectively. For hepatocellular carcinoma, CEUS had 0.66, 0.98 and 0.86 diagnosis sensitivity, specificity and accuracy; for the diagnosis of liver metastases 0.86, 0.99 and 0.94 sensitivity, specificity and accuracy. CEUS diagnostic sensitivity, specificity and accuracy for hepatic hemangioma and FNH were 0.79, 0.99, 0.95. and 0.54, 0.98, 0.95 respectively.
Conclusion: CEUS is a good imaging method for the diagnosis of FLLs, being able to differentiate between benign and malignant lesions with high sensitivity, specificity and accuracy, and to correctly diagnose the FLL’s pathological type.
