Overexpression of the aryl hydrocarbon receptor in frontal fibrosing alopecia and lichen planopilaris: a potential pathogenic role for dioxins?: an investigational study of 38 patients

Frontal fibrosing alopecia (FFA) and lichen planopilaris (LPP) are both lymphocytic cicatricial alopecias but with different clinical presentation. The recent and epidemic incidence of FFA worldwide suggests an environmental role in this disease. Dioxins are persistent organic pollutants and by-products of industrial activity with high affinity to the aryl hydrocarbon receptor (AhR).