Shammah - induced oral leukoplakia-like lesions

A Shammah-induced oral leukoplakia-like lesion is described in a 44-year-ol d Algerian patient, who used this specific chewing tobacco since 33 years. The extended white lesion was located to the right mandibular vestibule and had a homogeneous appearance. Shammah is a chewing tobacco consisting of p owdered tobacco leaves with carbonate of lime and other substances. It has been associated with oral cancer in Saudi Arabia. Histologically, acanthosi s, hyperortho- and parakeratosis were seen. The spinous cell layer showed l arge pale staining epithelial cells with pycnotic nuclei. Atypia was not ob served, however, an increase in mitotic activity was apparent. The subepith elial infiltrate was mild. Electron microscopy showed changes in the basal membrane with interruptions, duplications and triplications. Follow-up of t he patient for 2 years revealed that, whenever, the patient changed the loc ation of application, the white lesion regressed or disappeared within 4-6 weeks. Due to the composition of Shammah, the lesion induced has features o f a mucosal burn. In contrast to other smokeless tobacco variants, Shammah seems to cause changes which, according to the small number of reports, may transform into oral cancer. As such, Shammah-induced oral leukoplakia-like lesions may be considered precancerous. (C) 2001 Elsevier Science Ltd. All rights reserved.