BI31 Hereditary haemochromatosis: a risk factor for nonmelanoma skin cancer?

Abstract

Abstract Hereditary haemochromatosis (HH) is an autosomal recessive disease resulting in excessive levels of iron. In a recent study, in a US population of 448 patients diagnosed with HH, a positive association between HH and nonmelanoma skin cancers (NMSCs) was observed (Pan CX, Yang K, Lau CB et al. Non-melanoma skin cancer in patients with hereditary hemochromatosis: a case–control study. J Am Acad Dermatol 2023; 88:692–4). The authors also reported that, among those who required more frequent venesection, the risk of basal cell carcinoma (BCC) was particularly elevated. In terms of the possible pathomechanism, the authors noted that oxidative stress represents a key component in the pathogenesis of both HH and BCC. Ireland has the highest prevalence of HH in the world, with research suggesting approximately 1 in 83 people is predisposed. For this reason, a study was undertaken to determine if a similar association could be observed in an Irish population. A single-centre retrospective cross-sectional analysis was undertaken on a database of patients with haemochromatosis attending the venesection department of a tertiary referral centre over 25 years (1997–2022). All histologically diagnosed NMSCs within this patient group were then recorded. Ethical approval was granted by the local hospital ethics committee. There were a total 1480 patients in the database, 65% Male (n = 956). Five were excluded due to insufficient data. Thus, 1475 patients were analysed, 64% male (n = 949). The mean current age was 60 years (range: 19–100). Only 52/1475 patients (3.5%) had a histologically diagnosed NMSC, 52% male (n = 27). HH genetic mutation: C282Y homozygous (n = 29); H63D homozygous (n = 5); C282Y/H63D compound heterozygous (n = 11); and data not recorded (n = 7). Mean ferritin at HH diagnosis 575 (range: 0–8413). Forty-three patients were diagnosed with a BCC, 58% male (n = 25), with a total of 94 BCCs. Mean age was 67 years at first NMSC diagnosis. Histological classification: nodular (n = 48); superficial (n = 19); unclassified (n = 18); infiltrative (n = 5); micronodular (n = 3); and basosquamous (n = 1). Eleven patients were diagnosed with a squamous cell carcinoma (SCC), with a total of 21 SCCs. This study had limitations. It was a single-centre, retrospective study analysing only histologically confirmed NMSCs. It is acknowledged that a small proportion of NMSCs may be diagnosed clinically, specifically superficial BCCs without histological confirmation. Only records with histology available in our institution were recorded, and it is possible that NMSCs were excised in other institutions, potentially leading to an under-representation of NMSC incidence. The proportion of patients diagnosed with NMSCs in this cohort was relatively low, in contrast to the findings reported by Pan et al. This study indicates that HH is unlikely to represent an independent risk factor.