Hepatocellular carcinoma is a threat always looming within the cirrhotic liver. Although the differential for a liver mass theoretically can be relatively broad, application of a little clinical or imaging data can narrow the differential considerably.
For a patient with chronic hepatitis B or C, or with cirrhosis, suspicious enhancing masses have to be be considered hepatocellular carcinoma, unless there is convincing evidence otherwise. The LI-RADS classification was developed to help stratify what qualifies as "suspicious", but as long as you don't grab on to one aspect of a mass (e.g. a central "scar") and consider the mass in the context of the whole patient, you should be ok.
There are multiple different treatment options for HCC, which is one reason why risk stratifying them and describing them carefully is useful for the clinical team. Because this HCC was significantly exophytic, it was resected, but not all HCCs can be dealt with as straightforwardly.