Dysplasia/neoplasia surveillance in oral lichen planus patients: a description of clinical criteria adopted at a single centre and their impact on prognosis.

The concept of dysplasia/neoplasia surveillance has been applied to long-standing conditions associated with an increased risk of cancer. Although still controversial, periodic direct clinical examination as well as endoscopic techniques are currently performed in patients with inflammatory bowel diseases, Barrett's esophagus, and melanocytic skin lesions in order to detect and treat dysplastic or early malignant changes and therefore improve the patients' prognosis. It is not known if patients with oral lichen planus (OLP), a chronic inflammatory condition associated with an increased risk of cancer development, might benefit from such surveillance as well, nor how this should be performed. Here we present the clinical criteria we have adopted over a 12-year period to detect early malignant transformation of OLP, and report on their impact on the management and prognosis of patients. Overall data from 45 patients affected by 117 neoplastic events arising from OLP have been evaluated. Our dysplasia/neoplasia surveillance has led us to diagnose most episodes (94.9%; n.: 111) of OLP malignant transformation in early intraepithelial and microinvasive phases, namely stage 0 and I oral cancers (T(is) N0M0 or T1N0M0). The 5-year survival rate, where applicable, has been 96.7%. Advanced stage oral cancers have been diagnosed in six patients, three of whom have died. We suggest that the application of strict and rigorous clinical criteria in dysplasia/neoplasia surveillance could help clinicians to detect and treat early OLP malignant transformation and therefore improve long-term survival rates. Nevertheless, a small subgroup of patients has been shown not to benefit from such surveillance and to be characterized by a rapid development of advanced-stage oral carcinomas, with consequent poor prognosis.