P109 Frontal fibrosing alopecia: characterizing clinical classifications and their treatment response

Abstract

Frontal fibrosing alopecia (FFA) is a primary lymphocytic cicatricial alopecia that is characterized by progressive recession of the frontotemporal hairline resulting in a scarred and atrophic band. Despite its increasing incidence, its aetiology remains unclear. Three clinical patterns have been proposed to classify patients with FFA: pattern I is the linear pattern, pattern II diffuse or zigzag band, and pattern III the pseudofringe sign pattern. This study was designed to analyse the differences in classifications and evolution of patients with FFA, and assess treatment requirements and response. This retrospective cohort study was conducted at a UK tertiary hair clinic from February to December 2025 (data collection ongoing). Patients aged ≥ 18 years with a clinical or histopathological diagnosis of FFA were included. Demographics, FFA classification, age of onset, recorded measurements, biopsy findings, eyebrow involvement, symptoms, dermoscopic signs, time to achieve disease stability and treatments required were recorded. We identified 17 patients with a diagnosis of FFA, with 9 (53%) having biopsy confirmation. The average age of patients was 60 years (range 31–79), with the average age of onset being 50 years (range 28–72). Patients waited on average 5 years before being diagnosed with FFA (range 0–12). Eight patients (47%) achieved disease stability, requiring an average of 6 years (range 1–17). Thirteen patients (76%) had pattern I, two patients (12%) had pattern II and one patient had pattern III (one patient was not coded). There was no significant difference for mean age of onset between pattern I and pattern II/III (52 years vs. 44 years, P > 0.05), or in initial eyebrow involvement (P > 0.05). However, there was a significant difference in patients with pattern I being treated with systemics (hydroxychloroquine or methotrexate) compared with pattern II or III (13 vs. 0, P = 0.001). Our retrospective cohort study helps confirm the different FFA clinical classifications and provides insights into their clinical signs and treatment response.