Finasteride is of uncertain utility in treating frontal fibrosing alopecia

Frontal fibrosierende Alopezie – Fallbeispiele und Review

Die frontal fibrosierende Alopezie (FFA) ist eine vernarbende Alopezie, welche klinisch durch Regression des frontotemporalen Haaransatzes, disseminiert verbleibende Haare (lonely hairs) und Verlust der Brauen gekennzeichnet ist. Meist sind postmenopausale, seltener auch jüngere Frauen betroffen und gelegentlich auch Männer. Der Verlauf ist variabel, oft sehr langsam und unbeachtet. Auch Spontanremissionen sind häufig. Daher lässt sich die Inzidenz nur schätzen, jedoch ist sie wahrscheinlich zunehmend. Es werden dafür Umweltfaktoren, Sonnencremes, aber auch eine optimierte Awareness und Diagnostik diskutiert. Allerdings blieb die Pathogenese der lymphozytären Follikulitis bisher noch ungeklärt. Klinisch ist die Haut im betroffenen bandförmigen Bereich atroph und weißlich. In floriden Bereichen sind follikuläre Erytheme und Keratosen typisch. Nicht selten sind kleine, wenig erythematöse Papeln an Stirn und Wangen assoziiert („facial papules“). Evidenzbasierte Therapien existieren nicht. Lokal werden Steroide, Calcineurin-Inhibitoren oder Minoxidil angewendet, systemisch 5α-Reduktase-Hemmer, Hydroxychloroquin und Doxycyclin.

Frontal fibrosing alopecia shows robust T helper 1 and Janus kinase 3 skewing

BACKGROUND

Frontal fibrosing alopecia (FFA) is a scarring alopecia with unclear pathogenesis and a progressive course. The disease has a major impact on patients' quality of life and there is a lack of effective treatment to halt disease progression.

METHODS

We profiled lesional and nonlesional scalp biopsies collected in 2017 from patients with FFA (n = 12) compared with scalp biopsies from patients with alopecia areata (AA) (n = 8) and controls (n = 8) to evaluate gene and protein expression, including the primary outcome (CXCL9). We determined significant differences between biomarkers using a two-sided Student's t-test adjusting P-values by false discovery rate.

RESULTS

Significant increases were seen in CD8+ cytotoxic T cells, CD11c+ dendritic cells, CD103+ and CD69+ tissue-resident memory T cells in FFA and AA vs. control scalp (P < 0·05), with corresponding significantly upregulated granzyme B mRNA, particularly in FFA (P < 0·01). In AA, cellular infiltrates were primarily concentrated at the bulb, while in FFA these were mainly localized at the bulge. FFA demonstrated significant upregulation of T helper 1/intereferon (IFN) (IFN-γ, CXCL9/CXCL10), the Janus kinase/signal transducers and activators of transcription (JAK-STAT) pathway (STAT1, JAK3) and fibrosis-related products (vimentin, fibronectin; P < 0·05), with no concomitant downregulation of hair keratins and the T-regulatory marker, forkhead box P3, which were decreased in AA. The stem cell markers CD200 and K15 demonstrated significantly reduced expression only in FFA (P < 0·05).

CONCLUSIONS

These data suggest that follicular damage and loss of stem cells in FFA may be mediated through immune attack in the bulge region, with secondary fibrosis and reduced but still detectable stem cells. JAK/STAT-targeting treatments may be able to prevent permanent follicular destruction and fibrosis in early disease stages.

Frontal Fibrosing Alopecia: An Update on Pathogenesis, Diagnosis, and Treatment

Frontal fibrosing alopecia (FFA), first described by Kossard in the early 1990s, is a form of primary lymphocytic cicatricial alopecia characterized by selective involvement of the frontotemporal hairline and eyebrows. Since the original description, an increasing number of cases have been reported worldwide and the clinical aspects of the disease have been better characterized. However, the pathogenesis is still unknown and several hypotheses have been made about possible triggering factors, including hormones, neurogenic inflammation, smoking, UV filters, and ingredients in leave-on facial products. A genetic basis has also been hypothesized as the disease can occur in siblings and members of the same family. Besides its pathogenesis, research is also focused on treatment; FFA is a chronic condition and at present there is no validated or approved treatment for this disorder. Commonly prescribed topical treatments include corticosteroids, minoxidil, and calcineurin inhibitors. Systemic treatments include 5α-reductase inhibitors, hydroxychloroquine, and retinoids. Intralesional triamcinolone acetonide is also utilized, especially for the eyebrows. Other possible treatments include pioglitazone, naltrexone, tofacitinib, and lasers.

New Treatments for Hair Loss

The treatment of hair loss is an important part of clinical dermatology given the prevalence of the problem and great impact on patients' quality of life. Many new treatments have been introduced in recent years. This review summarizes the main ones in 4 groups: a) For androgenetic alopecia, we discuss new excipients for oral minoxidil, dutasteride, and finasteride as well as new forms of topical application; prostaglandin agonists and antagonists; low-level laser therapy; and regenerative medicine with Wnt signaling activators and stem cell therapy. b) For alopecia areata, Janus kinase inhibitors are reviewed. c) For frontal fibrosing alopecia, we discuss the use of antiandrogens and, for some patients, pioglitazone. d) Finally, we mention new robotic devices for hair transplant procedures and techniques for optimal follicular unit extraction.