These are sebaceous glands and other dermal adnexal structures found within the mouth. These are normally found in 80% of oral cavities of adults. Usually their numbers are very small. When present in large numbers it will be seen as streaks of individual glands along the interface between the skin of the lip and the vermilion border. The term Fox fordyce disease has been used to describe this condition. Fordyce first described this condition in 1896.
These granules appear whitish (rice like) / yellowish white. Usually they are asymptomatic papules size ranging from 1 - 3 mm in their greatest dimension. These granules remain almost static throughout life. Mucosa around these granules is normal.
Common sites involved:
1. Buccal mucosa (often bilateral)
2. Vermilion border of upper lip
3. Retromolar area of mandible
4. Tonsil (rare)
Sometimes rarely several adjacent glands may coalesce to form large cauliflower like masses (akin to sebaceous hyperplasia of skin). This condition may get labelled as sebaceous adenoma. Sebaceous carcinoma have been reported from these granules (very very rare).
These granules are usually not biopsied at all as they can be diagnosed just by inspection. Pathologist may encounter these granules incidentally in mucosal biopsies of buccal / labial areas. Histologically, these granules are similar to normal sebaceous glands of skin minus hair follicles. These glands conspicuously lack ductal communication with the surface of the mucosa. These glands lie in a submucosal plane, causing elevation of oral mucosa. Under microscope individual sebaceous cells are large with a central dark nuclei surrounded by abundant foamy cytoplasm. These glands may be surrounded by chronic inflammatory cells occasionally because of local trauma (teeth bite).
When large numbers of these glands coalesce, they form elevated benign masses known as sebaceous hyperplasia. When these masses get filled with keratin then they form pseudocysts which must be differentiated from dermoid cyst.
No active management is necessary other than for cosmetic reasons when present in the vermilion border of lip. If there is rapid increase in size or rare threat of neoplastic transformation surgical removal should be resorted to.