Figure 2. Pathologic presentation of a biting fibroma on the lower mucosal lip of an 80-year-old woman.

Distant (A) and closer (B, C, and D) views of the microscopic features of the biting fibroma from the patient’s lower lip are shown. There is slight thickening (acanthosis) of stratified squamous epithelium (black brackets). The underlying lamina propria contains collagen that is arranged in a radiating pattern (black asterixis). Numerous vessels (black arrows), some containing red blood cells, are also present in the lamina propria (hematoxylin and eosin stain: A, ×4; B, ×10; C, ×20; and D, ×40)