Squamous Papilloma-let's learn all you need to know

Squamous papilloma is the fourth most common oral mucosal mass
It is associated with papilloma virus ( Papilloma virus commonly causes skin warts)
Commonly caused by Human papilloma virus (HPV) types 6 and 11
Although all HPV lesions are infective, the squamous papilloma appears to have an extremely low virulence and infectivity & is not very contagious
Squamous papilloma may be clinically and microscopically indistinguishable from verruca vulgaris/common wart (the virus-induced focal papillary hyperplasia of the epidermis)

Exophytic growth made up of numerous, small finger like projections which result in a lesion with a roughened, verrucous or ‘cauliflower like’ surface
Nearly always a well circumscribed pedunculated tumor, occasionally sessile
Painless
Usually white but sometimes pink in color
COMMON SITE INTRAORALLY – tongue, lips, buccal mucosa, gingiva and palate, particularly area adjacent to the uvula
Majority of papillomas are only a few millimeters in diameter, but sometimes measure several centimeters
Occur at any age and are seen even in young children
COMMON WART/VERRUCA VULGARIS – Frequent tumor of the skin analogous to the oral papilloma. Uncommon on oral mucous membranes but extremely common on the skin. The associated viruses in verruca are the subtypes HPV-2, HPV-4 and HPV-40. Clinically it looks similar to oral papilloma, is contagious and capable of spreading to other parts of an affected person’s skin or membranes by way of autoinoculation. Lesions that are histologically identical to the verruca vulgaris of the skin are frequently found on the lips and occasionally intraorally. These are often seen in patients with verrucae on the hands or fingers, and the oral lesions appear to arise through autoinoculation by finger sucking or fingernail biting
Cowden’s syndrome – Papilloma like or papillomatous lesions as well as ‘pebbly’ lesions and fibromas of various sites in the oral cavity are recognized as one of the many manifestations of this syndrome.

Characteristic
Consists of many long, thin, finger-like projections extending above the surface of the mucosa, each made up of a continuous layer of stratified squamous epithelium and containing a thin, central connective tissue core which supports the nutrient blood vessels
Some papillomas exhibit hyperkeratosis, although this finding is probably secondary to the location of the lesion and the amount of trauma or frictional irritation to which it has been subjected
Essential feature is a proliferation of the spinous cells in a papillary pattern; the connective tissue present is supportive stroma only and is not considered a part of the neoplastic element
Occasional papillomas demonstrate pronounced basilar hyperplasia and mild mitotic activity which should not be mistaken for mild epithelial dysplasia
Koilocytes (HPV altered epithelial cells with perinuclear clear spaces and nuclear pyknosis) may or may not be found in the superficial layers of the epithelium
The presence of chronic inflammatory cells may be variably noted in the connective tissue