Potentially malignant disorders

There is range of potentially malignant disorders known. This article focuses on the most important – erythroplakia (erythroplasia), leukoplakia, and lichenoid lesions. Others such as actinic cheilitis, submucous fibrosis, Fanconi anaemia (syndrome) (table 1) are less common in the UK. The risk of malignant transformation in the potentially malignant disorders is approximately as shown in box 1.

Potentially malignant lesions are initially usually symptomless, so any symptoms should raise the index of suspicion of malignant change.

Erythroplakia

Erythroplakia (erythroplasia) is a rare red patch, usually related to tobacco and alcohol use, and seen in the middle aged and the older patient. Defined as a “fiery red patch that cannot be characterised clinically or pathologically as any other definable disease”, the clinical appearance is often of a flat or even depressed erythematous area of mucosa (fig 1). It is usually a solitary lesion. In some, there is a mixture of red and white changes - when the lesion is categorised as ‘erythroleukoplakia’, ‘non- homogeneous’ or ‘speckled’ leukoplakia. Histopathologically, erythroplakia typically shows at least moderate or severe dysplasia. Epithelial dysplasia is in general regarded as the most important indicator of malignant potential.