Betel chewer's mucosa--a review.

Betel chewer's mucosa (BCM) was first described and defined in 1971. Its clinical appearance is characterised by a brownish-red discolouration of the oral mucosa with an irregular epithelial surface that has a tendency to desquamate or peel off. The buccal mucosa is most frequently affected. The prevalence of BCM varies between 0.2% and 60% in different studies from South and Southeast Asia. Women are more frequently affected than men. Betel chewer's mucosa may be found together with other oral mucosal lesions such as leukoedema, leukoplakia and ulceration. The histological features are characteristic. The epithelium is often hyperplastic, and brownish amorphous material derived from the betel quid may be demonstrated not only on the epithelial surface but also intra- and inter-cellularly. Ballooning of epithelial cells may occur. The etiology is traumatic and possibly chemical. Betel chewer's mucosa is most likely not precancerous. Differential diagnoses include cheek biting, with which it has a number of similarities, and other predominantly white lesions that may have taken up stains from tobacco and other substances. The natural history of BCM should be studied in more detail and its association with other oral mucosal diseases, particularly of a precancerous nature, should be the aim of further investigations.