Squamous Papilloma (papilloma)

Verruca vulgaris

Condyloma acuminatum

Papillary proliferation of surface stratified squamous epithelium which is sometimes keratinized --epithelium, thicker than normal, retains usual pattern of cellular maturation; occassionally increased basilar hyperplasia and mitotic activity but not dysplasia

Papillary projections supported by mature fibrovascular CT --may be some inflammatory infiltrate depending on trauma, etc.

Found in children mostly

In mouth on vermillion border of lip, labial mucosa, anterior tongue

Presents painless papule or nodule w/ papillary projections or rough pebbly surfaces

Pedunculated or sessile

Enlarges rapidly to max size of 5 mm; can enlarge if irritated and often multiple lesions clustered

Cutaneous pink, yellow, or white; oral almost always white

May produce cutaneous horn

Proliferation of hyperkeratotic stratified sq epi into fingerlike projections w/ CT cores, sometimes accompanied by inflammation

Elongated rete ridges tend to converge toward center of lesion producing "cupping effect"

Prominent granular cell layer (hypergranulosis) characterized by coarse, clumped keratohyaline granules

Abundant koilocytes w/ perinuclear clear spaces and small, dark (pyknotic) nuclei in superficial spinous layer

Eosinophilic intranuclear viral inclusions in granular cells

Skin: successful by topical salicylic acid, topical lactic acid or liquid nitrogen cryotherapy

Oral: surgically excised or destroyed by laser, cryotherapy or electrosurgery

Most commonly diagnosed in teenagers & young adults; wide age range

Most common locations: labial mucosa, soft palate, lingual frenum

Typically sessile, pink, well-demarcated, nontender exophytic mass w/ short, blunted surface projections

Tend to be larger than common papilloma (1-1.5 cm)

Often clustered with others

Proliferation of stratified sq epi w/ only mildly keratotic & blunted papillary projections

Often separated by keratin-filled crypts, and supported by fibrovascular CT cores

Proliferating epithelium is mature and differentiated, but spinous layer contains koilocytes

Oral lesions: conservative but complete surgical excision w/ care taken to confine associated aerosol

Anogenital lesions: treated more by topical agents

Care must be taken to avoid spreading to adj or non-adj mucosa

Prognosis generally good but anogenital lesions may be infected w/ high risk HPV types 16, 18 (not oral lesions)

Most common in whites

40-70 y/o

Slight M>F

Most common site: oral mucosal, half on gingiva and alveolar mucosa (but can be seen at any other sites)

Well-demarcated soft painless, sessile, slightly elevated mass w/ white, yellow-white or red color and papillary or roughened surface

<2 cm, never >4 cm

Resemble papilloma, condyloma, rarely early carcinoma

Papillary acanthotic surface epi covered by thickened parakeratin which fills crypts b/t papillary projections

Fibrous supporting CT deep to and b/t descending rete ridges packed w/ lipid-filled macrophages (foam cells)

Conservative surgical excision

Recurrence after excision rare & malignant transformation has not been reported

Unknown but positive correlation w/ chronic sun exposure, sometime w/ hereditary (auto dom) tendency

Mutaitons in FGFR3 may be important

Does not occur in Oral cavity itself

Begins to dev on skin of face, trunk, and extremities during 4th decade of life, increasing prevalence w/ each passing decade

Lesions usually multiple, beginning as small tan to brown macules, then enlarging and elevating

Surface may be smooth, fissured, pitted or verrucous, appearing to be stuck onto skin, usually less than 2 cm

Exophytic prolilferation of basilar epi cells w/ varying degrees of surface keratinization, acanthosis & papillomatosis

Typically entire epi hyperplasia extends upward, above normal epidermal surface rather than extending into CT

Exhibit keratin-filled invaginations that appear cystic in cross-section (horn cysts or pseudo-horn cysts)

Melanin pigmentation often prominent in basal layer of epi

Irritation may alter histologic features to make epi more squamatoid: important not to mistake for epidermoid carcinoma

Encountered at any age and either gender

Most common site: vermillion border of lower lip (33%), buccal mucosa, gingiva, palate

Usually solitary (17% multiple) well-demarcated, uniformly tan to dark-brown asymptomatic, round or oval macule 7 mm in diam or smaller; occassionally blue or black

Increase in melanin (perhaps melanocytes) in basal and parabasal layers of otherwise normal surface stratified sq epithelium

Melanin can also be found free in CT or within macrophages (melanophages)

Lesion that has been unchanged for long period of time, no treatment necessary

Oral pigmented macule of recent onset, large size, irregular pigmentation, unknown duration, or recent enlargement biopsy and histologic exam is mandatory