PSMA6 and hepatocellular carcinoma: Serum levels of alpha 1-antitrypsin (alpha 1 AT) were measured by radial immunodiffusion and phenotypes were determined by electrofocusing in acrylamide gel in 39 patients with hepatocellular carcinoma (HCC) positive for serum hepatitis B surface antigen (HBsAg), 41 patients with HCC negative for serum HBsAg, and 160 age- and sex-matched hospital controls.