Abstract: The present invention pertains to novel diagnostic procedures for the prognosis, diagnosis and monitoring of liver diseases such as hepatocellular carcinoma (HCC). The present invention provides sphingolipids and especially long chain ceramides as significant and highly prognostic serum biomarkers in HCC compared to liver cirrhosis. Therefore the invention in particular provides a method for detecting the presence or absence of a HCC in a liver cirrhosis patient using the disclosed biomarkers. Also provided is a method for monitoring the treatment success of a HCC treatment by monitoring the disclosed serum biomarkers. Finally the invention pertains to diagnostic kits for performing the disclosed methods of the invention.