The left lateral border of the tongue mucosa was biopsied under local anesthesia. An elongated piece of about 8 X 4 X 4 mm in greatest dimensions was removed and submitted for microscopic examination. The area healed within a short period of time. Based on the results of the incisional biopsy, the patient was advised to completely stop the use of the Nicorette gum and switch to a cutaneous nicotine patch.

Incisional Biopsy

Histologic examination reveals a hemisected piece of soft tissue composed of keratinized surface epithelium with underlying fibrous connective tissue (Figure 5). The surface epithelium is covered by a thick layer of parakeratin which is superficially infiltrated by bacterial colonies (Figures 5 & 6). The spinous layer is of increased thickness and shows evidence of reactive atypia in the form of cells with large nuclei and prominent nucleoli (Figure 6). The connective tissue is infiltrated by a few lymphocytes, plasma cells & occasional neutrophils.

Figure 5 Low power (x40) H & E histology shows a fragment of oral mucosa with a thick keratin layer covered by bacterial colonies. The spinous layer is of increased thickness. The connective tissue is infiltrated by lymphocytes and plasma cells.

Figure 6 Higher power (x100) H & E histology of the surface epithelium and keratin layer with bacterial colonies.