Most patients with hepatocellular carcinoma (HCC) also have cirrhosis, an independent cause of death. We considered an alternative definition of tumor-related death in patients with HCC and attempted to validate our definition. Two hundred thirty-seven HCC patients were diagnosed, followed, and died over a 12-year period and were evaluated every 2 months, including their last 6 months of life. We defined death by cancer if there was, in the last 6 months of life, a CT scan increase of >25% in the sum of tumor index lesions' cross-sectional areas or new onset of, or increase in, either vascular invasion or metastatic disease (Group 1). Patients with stable cancer were considered to have died from any other cause (Group 2). We found that 135 (57%) patients died from cancer progression (Group 1), whereas 102 (43%) patients did not (Group 2). There was a statistically significant difference between Group 1 and Group 2 patients in percentage with bilobar disease (P = 0.03), more than one tumor (P = 0.01), an increase in AFP (P = 0.04), vascular invasion (P = 0.001), and the presence of metastases (P = 0.01). We conclude that 57% of patients with unresectable HCC died as a direct result of cancer progression, but 43% did not. The latter died from complications of their cirrhosis, including sepsis, GI bleeds, and renal failure.