Risk of Hepatocellular Carcinoma in Patients with Porphyria: A Systematic Review

Acute porphyrias are a group of metabolic disorders resulting in defective porphyrin synthe-sis and reduced heme production, which carries a risk of malignancy. Porphyrias are inborn defects in the heme biosynthesis pathway resulting in neurovisceral manifestations and cutaneous photosensi-tivity attacks with multi-systemic involvement. Its estimated prevalence nears 5 per 100,000 patients worldwide. Subclinical liver disease is common, which can progress into transaminitis, fibrosis, cirrhosis, and malignancy. However, data on the incidence of primary liver cancer are lacking. We aim to determine the risk of hepatocellular carcinoma (HCC) in patients with porphyria. A systematic review and pooled analysis were conducted through 2021 on studies assessing blood tests, imaging, cancer development, liver transplant, surgical resection, and outcomes in porphyria. In total, 19 studies, which included 7381 patients with porphyria (3476 females), were considered for the final review. In eight studies, alpha-fetoprotein levels were elevated between 200 and 1000 IU/mL. Of the total cohort of patients with porphyria, primary liver cancer was diagnosed in 351 patients (4.8%), of whom 243 (3.3% of the total) were found to have HCC. A subset of patients was found to have cholangiocarcinoma (n = 18; 0.3% of the total). Interestingly, advanced liver disease or cirrhosis was not a prerequisite for the formation of HCC in a small group of patients. Of the total cohort, 30 patients underwent liver resection, 48 patients underwent liver transplantation, and 327 patients died. Patients with porphyria are at risk of developing primary liver malignancy. Further studies should aim to develop diagnostic and prognostic models aimed at the early detection of HCC in porphyria.