Abnormal tissue

When recalling our brief discussions of the challenges in the diagnosis of (and prognosis for) lesions of the oral mucosa (lining of the mouth), it will not come as a surprise that management and treatment of these lesions is controversial. The only generally agreed action is a close observation and review scheme for these lesions when they have an appearance described as moderate or severe. To do otherwise would place an intolerable and counterproductive burden on patients and healthcare resources.

Neither clinical appearance of dysplastic lesions nor histophathology findings after an incisional (or excisional) biopsy have much predictive power as to a likely development of such mucosal lesions (it could be anything from spontaneous resolution to rapid development of an oral malignancy, and anything in between (such as simply no progression)). Many molecular biomarkers have been suggested, alongside other metrics (such as the severity of the dysplasia, and/or size and location of the lesion) in the hope to have a predictive and non-invasive tool available at the diagnostic stage. Genomics, to date, have also failed to perform a useful predictive function. For the time being, there is no such predictive tool.

This leaves patients and clinicians with a dilemma as far as treatment options are concerned, a challenge for all involved: where should the line be drawn, given that the majority of oral mucosal lesions are benign and will never progress to a malignant disease and that recurrence of many of these lesions seems to be independent of surgical removal.

Aggressive surgical removal of any such lesions is advocated by some clinicians. Other clinicians take a more conservative view and advocate more of a ‘wait and watch carefully’ policy. Any policy will include biopsies as an instrument to exclude malignancies. Laser excision has been proposed as a slightly less invasive approach, given the good healing tendencies of laser wounds. Reducing the morbidity from multiple, repeated biopsies and/or excisions of these lesions, possibly over many years, is undoubtedly an important consideration.

Apart from the debated surgical excision strategies for dysplastic oral mucosal lesions, non-surgical treatments include application of topical corticosteroids, a variety of ineffective mouth rinses, topical retinoids and even topical bleomycin. There is no convincing evidence of the efficacy of any of these ‘chemopreventive’ measures.