Malignant transformation of oral lichen planus. A retrospective analysis from 2003-2014: our experience.

AIM: The aim of the study is to describe both the clinical characteristics and the prevalence of Oral lichen planus (OLP) in a group of patients from a region of Southern Italy. MATERIAL AND METHODS: Among the patients who referred to outpatient visit, 96 (35 men and 61 women) received diagnosis of OLP according to Van der Meij and Van der Wall criteria. RESULTS: Nine of ninty-six cases observed developed squamous cell carcinoma (9,37%). The risk of malignant transformation was significantly higher among OLP patients who smoked (OR=2,5 P< 0,05), consumed alcohol (OR=3 P< 0,05), came from the province with a ratio province: city of 4,5:1 and had the reticular form (44.4%). DISCUSSION: Oral lichen planus (OLP) is an oral subtype of lichen planus with a prevalence in the world population estimated between 0.22% and 5% and an incidence approximately of 2.2%. The analysis of our results revealed an important information about the prevalence of malignant transformation, which is 9.37%. CONCLUSION: The transformation of the oral lichen planus may not be as rare as one would expect. The malignant transformation rates of OLP are underestimated due essentially to restrictive diagnostic criteria, inadequate follow-up periods, and/or low quality of studies. Close surveillance is mandatory to monitoring the growth and evolution of lesions in order to reduce the morbidity of OSCC. KEY WORDS: Malignant transformation, Oral lichen Planus, Squamous cell carcinoma of the oral cavity.