Oral and Genital Lichen Planus: A Comprehensive Review of Co-Manifestation

Abstract Lichen planus (LP) is a chronic immune-mediated inflammatory disease affecting skin, mucosa, nails, and hair. Oral lichen planus (OLP) affects 1–3% of adults aged 30–60 years and exhibits a female predominance. Genital lichen planus (GLP) often co-occurs with OLP but is underdiagnosed due to asymptomatic or subtle presentation. Studies indicate that 19–57% of OLP patients—with up to 92% asymptomatic genital involvement—have GLP. Erosive variants pose a 1–4% risk of malignant transformation. The disease is driven by CD8⁺ T-cell–mediated basal keratinocyte apoptosis, involving genetic predisposition (e.g., HLA‑DQB1*0201), infections (HCV, HPV), stress, and medications. Diagnosis requires thorough mucosal examination and histopathological confirmation. First-line management includes topical corticosteroids; systemic immunomodulators and emerging therapies such as JAK inhibitors are increasingly used. Multidisciplinary care with biannual-to-annual monitoring is essential given functional morbidity and cancer risk.