Screening for hepatocellular carcinoma in acute intermittent porphyria: a 15-year follow-up in northern Sweden

Abstract

To evaluate the benefit of screening for hepatocellular carcinoma (HCC) in gene carriers of acute intermittent porphyria (AIP) and estimate the annual incidence of HCC in this group. All AIP gene carriers aged ≥55 years from the northernmost county in Sweden, Norrbotten, were invited for screening in this prospective study every 1-1.5 years during the period 1994-2009. We registered all HCC cases amongst AIP gene carriers in the northern region of Sweden (four counties). We compared gene carriers with repeated screening intervals of <2 years (Group A) with controls (Group B; i.e. gene carriers who had never been screened, those screened for the first time or screened at intervals of >2 years, or dropouts). The screening included radiological examination of the liver and relevant laboratory tests. A total of 62 AIP subjects participated in the study, comprising 33% of the total AIP population aged >55 years in the northern region of Sweden. HCC was diagnosed in 22 AIP subjects (12 men and 10 women), mean age 69 (59-82) years. Amongst these subjects, 73% had experienced prior AIP attacks. The incidence rate ratio for HCC was 64 (52 in men and 93 in women). There were no cases of hepatitis B/C or alcohol abuse. Liver cirrhosis was rare. Liver resection could be performed in most subjects in Group A. Fourteen patients died of HCC, one in Group A and 13 in Group B. Compared with those who were not screened regularly, screening was associated with improved 3-year and 5-year survival (P = 0.005 and 0.038). Screening for HCC in carriers of AIP enables early diagnosis and a choice of potentially curative treatments with improved prognosis. We recommend annual screening using liver imaging for AIP gene carriers >50 years of age.