INTRODUCTION
Frontal brosing alopecia (FFA) is a lymphocyte-mediated primary cicatricial alopecia predominantly affecting the frontal hairline. It was first described by Kossard in 1994. The clinical characteristic of FFA is a progressive and symmetrical recession of the frontotemporal hairline.1 In most patients, the disease is accompanied by the loss of eyebrow hair. Some patients also lose body hair and show facial papules.2,3 Although the disease typically affects postmenopausal women, there were also described certain cases where it was observed in younger women and men.4,5 FFA is a disease entity with many unknowns, including its exact pathogenesis or most efficacious treatment. The course of the disease is usually progressive. On average, the frontotemporal hairline recedes by 0.4 - 1.7 mm per month.3 Hair loss is permanent and irreversible. Lonely hairs, surrounded by areas of fibrosis, are present in most patients. FFA is a lymphocyte-mediated primary cicatricial alopecia. It shares histopathological features with lichen planopilaris (LPP) and presents with reduction in the number of hair follicles, perifollicular lymphocytic inflammatory infiltrate, and fibrosis.6,7 FFA is currently recognized as a subtype of lichen planopilaris. Treatment strategies for LPP depend on disease severity, patient age, and preferences, as well as physician experience.8-10 As for all types of cicatricial alopecia, the key objective of treatment is to alleviate symptoms and halt the scarring process. First-line treatments for LPP include ultrapotent topical corticosteroids or intralesional corticosteroids injections.9,11-13 Other suggested treatment modalities include the oral administration of prednisone, cyclosporine, mycophenolate mofetil, azathioprine, hydroxychloroquine, thalidomide, tetracycline, and griseofulvin.8,9,11,12,14 Some authors suggest the use of retinoids in treating patients with LPP who showed no or only partial response to at least first-line or second-line drugs.8,13 Although the mechanism of action of retinoids is not yet clearly understood, it may involve either the normalization of the hair follicular keratinocyte antigen expression and the suppression of inflammatory cellular infiltration.15 Literature describes some cases where acitretin, isotretinoin, and etretinate were used in LPP,9,11,13,16 but not in FFA.
METHODS
The aim of this retrospective study was to assess the efficacy of systemic retinoids in FFA treatment. It was carried out in the form of a retrospective analysis (2007-2017) and approved locally by the Institutional Review Board. The inclusion criteria for participation in the study were as follows: the diagnosis of FFA and the completion of training on retinoid or finasteride treatment. The diagnosis was based on clinical evaluation, trichoscopy and, in doubtful cases, on pathology evaluation. Twenty-nine patients were treated with 20 mg isotretinoin daily. Eleven patients