BI06 Short sharp shock or slow burn: clinician perspectives on treatment of actinic keratoses with 5-fluorouracil 5% cream monotherapy vs. 5-fluorouracil/calcipotriol ointment combination therapy
Authors: Junejo Muhammad Hyder , Carucci Margherita , Hurt Chris , Adams Richard , Matin Rubeta , Proby Charlotte , Harwood Catherine 
Published: June 2023

Abstract
Actinic keratoses (AK) are common in immunocompromised patients and associated with increased risk of cutaneous squamous cell carcinoma (cSCC). The current standard of care is 5-fluorouracil cream 5% (5-FU) monotherapy for 4 weeks. In recent years, 5-FU cream and calcipotriol ointment (5-FU-Cal) combination AK therapy for 4–6 days has emerged as potentially more effective and better tolerated, although the original randomized controlled trial (RCT) excluded immunosuppressed patients. Previously, we shared immunosuppressed patients’ real-world perspectives of using 5-FU monotherapy vs. 5-FU-Cal combination therapy (Junejo MH, Demirel S, Matin R et al. Short shock or slow burn? Patient perspectives on treatment of actinic keratoses with 5-fluorouracil 5% cream monotherapy versus 5-fluorouracil plus calcipotriol combination therapy. Clin Exp Dermatol 2023; 48:31–2). The majority (81%) found 5-FU-Cal to be more effective than 5-FU monotherapy. Despite 47% reporting worse local skin reactions (LSRs), most preferred the 5-FU-Cal combination. We now report results from a clinician survey on the use of 5-FU monotherapy vs. 5-FU-Cal combination therapy for the treatment of AK. An online survey was sent to 200 UK consultant dermatologists. Fifty-seven (28.5%) completed the survey, all of whom reported using 5-FU monotherapy for treating AK in patients with prior cSCC; 43 (75%) reported this to be their preferred treatment. Most clinicians (n = 40; 70%) were aware of 5-FU-Cal combination therapy, although only 24 (42%) reported using it to treat AK in patients with prior cSCC. Of these, 18 (75%) used combination treatment for AK as part of field change, 14 (58%) used it for the treatment of patches of more than five AK and 13 (54%) used it for grouped AK. Very few (n = 4; 17%) used combination therapy for treatment of cSCC in situ (n = 4), single AK (n = 3) or superficial basal cell carcinoma (n = 1). Of 24 clinicians using 5-FU-Cal, the majority felt that patients developed LSRs often (n = 11; 46%) or always (n = 7; 29%); fewer felt that LSRs occurred sometimes (n = 5; 21%) or rarely (n = 1; 4%). Clinicians using combination therapy primarily felt the LSRs were moderate but not severe enough to require supplementary treatment or discontinuation (n = 17; 71%). Half (n = 12; 50%) of those using combination therapy felt patients did not signal a preference between 5-FU monotherapy vs. 5-FU-Cal combination therapy. Two-thirds (n = 38/57; 67%) of clinicians reported an interest in participating in a RCT comparing 5-FU vs. 5-FU-Cal vs. sunscreen alone for the treatment of AK in patients with prior cSCC. This is the first evaluation of clinician perspectives on the use of the newly emerging 5-FU-Cal therapy for AK. These data provide a rationale for the inclusion of combination 5-FU-Cal therapy in future studies using topical AK treatments for cSCC prevention in the UK.