Focal epithelial hyperplasia
What is focal epithelial hyperplasia?
Focal epithelial hyperplasia is a specific human papillomavirus (HPV) infection in the mouth. It is also known as Heck disease.
Who gets focal epithelial hyperplasia?
Focal epithelial hyperplasia has been reported worldwide, but is particularly common in small native communities such as among North, Central and South American Indians and Inuit. An incidence as high as 30% has been reported among Inuit and children from some communities in Venezuala. It is rare in Caucasian populations.
Risk factors for this condition include poor hygiene, poverty and communal lifestyles. Extensive lesions have been reported in association with HIV infection / AIDS.
It is most commonly seen in children and young adults. Some authors report family clustering of cases. There is no difference between the sexes.
Clinical features of focal epithelial hyperplasia
Focal epithelial hyperplasia only affects the lining of the mouth, most commonly:
- inside of the lips
- inside of the cheeks
- sides of the tongue
However, the gums and tonsil area can also be involved.
It most commonly presents as a soft smooth flat-topped slightly raised cobblestoned appearance. It is usually the same colour as the rest of the mouth, but sometimes paler. There are often multiple lesions of less than 1cm in diameter.
In general, focal epithelial hyperplasia is asymptomatic. It may present because of the appearance, a feeling of roughness or accidental biting of a lesion.
How is focal epithelial hyperplasia diagnosed?
Focal epithelial hyperplasia may be suspected clinically, particularly in high risk populations.
A biopsy from a lesion in the mouth will show diagnostic pathology – the epithelium is very thickened and raised above the surrounding mucosa with typical ‘mitosoid’ cells.
The diagnosis can be confirmed by the detection of HPV 13 or 32 DNA following PCR on a scraping taken from a lesion, or by in situ hybridization of biopsy specimens. In some cases, particularly in children, a mucosal scraping to confirm the specific HPV types, rather than a more invasive biopsy, is all that is required to confirm the diagnosis. The identification of the specific HPV type may be important in cases of suspected child sexual abuse as HPV 13 and 32 have only ever been detected in the oral mucosa.
Treatment of focal epithelial hyperplasia
This is a benign condition with no cases of oral cancer reported to have developed. It therefore usually does not require treatment unless lesions are of aesthetic concern or if accidental or deliberate biting of lesions occurs.
Treatment options then may include excisional biopsy, CO2 laser or diathermy. Successful use of topical imiquimod 5% cream has been reported. Followup is recommended in all cases.
Natural history of focal epithelial hyperplasia
The natural history of focal epithelial hyperplasia is currently unclear, although it does seem to persist for many years.
Some surveys claim there is no difference in the incidence between children or adults although the clinical appearance may be different, with adults having fewer and flatter lesions than children. Others have reported involvement only of children, and therefore a presumed resolution of the condition by adult life.