Letter to the editor: oral lichenoid disease. A new classification proposal.

In the last few years there has been a special interest in the definition and classification of so called “premalignant oral diseases” (1). Frequent and controversial processes such as oral lichen planus and other similar oral lesions are included in this group (2, 3). Oral lichen planus is clinically characterized by white papular lineal lesions which show a reticular pattern, associated or not with other lesions (2,3). However, this papular lesion is not a pathognomonic feature of oral lichen planus. For this reason the term of “lichenoid lesion” is used for the clinical situations where multiple, symmetric and bilateral characteristics are not found (2-4). Several authors (1-5) have pointed out the clinical and histological problems when trying to differentiate between “oral lichen planus” and “oral lichenoid lesions”. Recently, several studies (3, 6, 7) have shown the importance of a correct diagnosis of these lesions due to the great difference in the prognosis. According to this data, and with the objective of trying to clarify this pathology, I propose the following classification which I name “Oral lichenoid disease” (OLD). This disease has as a starting hypothesis: 1.The so called “oral lichen planus” represents a spectrum of different processes, the fundamental nexus of which is the clinical presence of white lineal papulae. 2.The “white lineal papulae” is a clinical aspect which represents an unspecific reaction of the oral mucosa that may have multiple etiopathogenesis and different histological patterns. 3.The correct diagnosis of any of these processes demands the knowledge of the clinical, histopathological and evolutive data. 4.Each subtype of oral lichenoid disease shows a different malignant potential.