O05 Risk of keratinocyte carcinomas in patients with psoriasis treated with biologic therapy: analysis from the British Association of Dermatologists Biologics and Immunomodulators Register (BADBIR), on behalf of the BADBIR Study Group
Authors: Esse Shamarke , Alabas Oras , Mason Kayleigh , Ryan Sarah , Reynolds Nick J , Smith Catherine , Bunker Christopher , Griffiths Christopher , Green Adele , Warren Richard B 
Published: June 2024

Abstract
Previous literature suggests an association between the use of biologics and the development of keratinocyte carcinoma in psoriasis. Our aim was to evaluate the risks of developing basal cell carcinoma (BCC) and cutaneous squamous cell carcinoma (SCC) in patients with moderate-to-severe psoriasis treated with biologic therapy compared with those receiving nonbiologic systemic therapy. We used data from BADBIR, a multicentre register evaluating the long-term safety and effectiveness of systemic therapy for patients with moderate-to-severe psoriasis, between September 2007 and November 2023. Data are linked with additional keratinocyte carcinoma events recorded in NHS Digital. Patients (Fitzpatrick skin types I–IV) with chronic plaque psoriasis, who were biologic naive at registration to BADBIR, with no history of any cancer, and who had completed at least one follow-up visit, were eligible for study inclusion. To balance between the compared groups in their baseline characteristics, we calculated probability-weighted regression adjustment estimators with a propensity score model including age, sex, previous acitretin, previous ciclosporin, and number of courses of psoralen and ultraviolet A or narrowband ultraviolet B. These weights were therefore used in a flexible parametric survival model to estimate hazard ratios (HRs) for developing incident BCC and SCC, using imputed data. In total, there were 9303 patients (67%) registered to the biologic cohort and 4622 patients (33%) in the nonbiologic systemic cohort. The biologic cohort was older (median age 44 years, interquartile range 35–53) vs. median 42 years, interquartile range 32–53), with more men (58% vs. 56%) and comorbidities (68% vs. 61%) compared with those in the nonbiologic systemic cohort. Patients in the biologic cohort contributed 62 141 and 62 433 person-years of follow-up for the BCC and SCC analyses, respectively, while patients in the nonbiologic systemic cohort contributed 19 565 and 19 592 person-years of follow-up. In total, 119 patients (1.3%) developed first BCC and 60 patients (0.6%) developed first SCC in the biologic cohort during follow-up. In the nonbiologic systemic cohort, 28 patients (0.6%) developed first BCC, with 17 patients (0.4%) developing first SCC. These differences in risk of developing first BCC or SCC were not statistically significant between the two cohorts: for BCC, adjusted hazard ratio (aHR) 1.18, 95% confidence interval (CI) 0.71–1.95; and for SCC, aHR 0.91, 95% CI 0.41–1.73. The findings from these real-world data showed no increased risk of BCC or SCC for biologic-treated patients compared with those receiving nonbiologic systemic therapy. However, caution is needed in interpreting the current findings due to the small number of first events. This study is funded by the Psoriasis Association.