How can liver cirrhosis and liver cancer be differenciated???

Usually: Primary liver cancer (hepatocellular carcinoma, or HCC) can usually be seen on modern ct scan, or PET-ct scan. It is usually seen as a separate mass within a nodular, shrunken liver if cirrhosis is present. Definitive diagnosis is usually made with a biopsy of the tissue, often done by an interventional radiologist. No scan however is perfect. Hope this helps.

Cirrhotic at risk: liver cancer usually happens in a cirrhotic liver. cirrhosis = scarring of the liver, cancer = uncontrolled cell growth. if you really have cirrhosis, you need to be screened for cancer regularly (can happen in 1-3% of cirrhotics per year)