Clinical characteristics, management, and malignancy rate of oral lichen planus: A European multicenter study.

Introduction: Oral lichen planus (OLP) is a chronic inflammatory mucocutaneous condition that includes a spectrum of oral clinical manifestations ranging from mild painless white lesions to painful erosions and ulcers. The purpose of this European multicenter study is to describe the general characteristics of OLP lesions, the clinical and histopathological diagnosis, and the management of OLP at different European Oral Medicine and Maxillofacial Surgery centers, in order to minimize selections biases and provide information about the current trends in the treatment of OLP across Europe.

Materials And Methods: Data and histopathological records of patients with OLP were retrospectively revised and only those patients that fulfilled the diagnostic criteria from the 2016 position paper by American Academy of Oral and Maxillofacial Pathology were included. The following data were recorded for each patient: gender, age, voluptuary habits, risk factors for OLP (psychological stress, medications, systemic diseases), location of OLP lesions, clinical presentation, patterns of clinical expression, symptoms, treatment, possible clinical improvement, and malignant transformation.

Results: A total of 565 OLP patients (422 females, 143 males) fulfilled the inclusion criteria. The mean age of the study population at diagnosis was 60.11 years. In 262 patients (46.4 %), just a site of OLP was identified: in 186 of these "one-site" patients, OLP was diagnosed just in buccal mucosa. The most frequently observed clinical pattern was reticular. When evaluating the treatment received, 294 patients were kept in follow up with a Wait-and-see approach. The most frequent treatment regimen was the use of topical corticosteroids (123 patients). A significant statistical association was found between the prescription of topical corticosteroids (P < .0005) or retinoids (P < .000005) and symptoms improvement. Squamous cell carcinoma associated with OLP lesions was observed during the follow-up in 9 OLP patients out of 565 (1.6 %).

Conclusions: Reticular and mixed clinical patterns are the most frequent subtypes of OLP. The use of topical corticosteroids and retinoids for the management of OLP seems to allow good improvement results of symptoms and signs. A clinical long-term follow-up is fundamental due to the chronic nature of OLP and possible malignant transformation.