[New knowledge on the diagnosis of oral leukoplakia]

There have been many discussions and debates in the literature over appropriate criteria for diagnosing oral leukoplakia and for predicting its prognosis.

In general, two clinical variants of leukoplakia are being recognised: the homogeneous and non-homogeneous type. Clinical subdivisions of leukoplakia in these two types can be used for cases in which no biopsy is available.

A 2-4 week interval to observe a possible regression or disappearance of a white lesion, after elimination of possible causative factors, seems to be a fully acceptable period of time before taking a biopsy. Taking a biopsy in homogeneous leukoplakia and especially non-homogeneous leukoplakia should be a standard rule. It is recommended that the histologic report should include a statement on absence or presence of epithelial dysplasia and an assessment of its severity. This recommendation was made in order to provide a classification and staging system reflecting the size and histopathologic findings.