In 67 patients (mean age 51 years, range 26-79), at diagnosis of primary haemochromatosis (PH), grade III or IV liver iron overload was present in all cases, cirrhosis in 85%, transferrin saturation greater than 80% in 75%, serum ferritin greater than 1000 micrograms/l in 84%, and overt diabetes in 48%. Alcohol intake was greater than 150 g/day in 11 patients; six were chronic hepatitis B surface antigen (HBsAg) carriers. HLA-A3 and B7 antigens were present in 64% and 23% versus respectively 22% (p less than 0.01) and 9% (p less than 0.025) in controls. Iron overload was found in the stomach, duodenum, skin and bone marrow in 57, 43, 45 and 59% of the patients studied. Sixty-three patients were followed for 1-260 months (median 24); 43 received regular iron-depleting treatment and 20 did not because of liver failure, cancer or refusal. Cumulative survival was 79%, 67% and 61% at 1, 4 and 10 years, respectively. Ten patients died from hepatocellular carcinoma and two from extrahepatic cancer. The early high mortality rate was due to some cases of advanced disease or cancer. Cumulative survival in the regularly treated group was 95% at 1 year and 91% at 4 and 10 years, which was higher than in the untreated group.