Almost exclusively blakcs

Female

3rd/4th decades

Most common sites: buccal mucosa, lips, palate, gingiva, alveolar mucosa

Most solitary; but bilateral or multifocal involvement has been reported

asymptomatic; but pain, burning, pruritus been reported

Smooth, flat, or slightly raised

Dark brown to black

Rapid increase in size

Numerous benign dendritic melanocytes (norm confined to basal layer of epi) present throughout lesional epi

Basal melanocytes also increased in number

Spongiosis (intercellular edema) & acanthosis (thickening of spinous cell layer)

May be accompanied by inflammation in CT

Must be biospied to rule our melanoma, etc.

Then no further treatment necessary

(Both spontaneous regression after incisional biopsy, and recurrence or development of more lesions have been reported rarely)

Malformations of skin or mucosa which occur congenitally or developmentally and which represent proliferations of nevus cells

Melanocytic nevus cells located superficially are relatively uniform, round to ovoid w/ centrally located basophilic nuclei, varying amounts of eosinophilic cytoplasm and varying amounts of intracytoplasmic melanin

Deeper cells, more elongated and spindle-shaped they become, looking more like fibroblasts and Schwann cells, w/ little melanin

Begin as junctional --> compound --> intradermal

Deeper the nevus cells, less prominent melanin production

Begin to dev on skin in childhood, most appearing by 35

F>M

Caucasians>Asians or Black

Most above waist, head and neck

Nevus on skin usually begin as flat, well-circumscribed brown to black macule, usually <6mm diam (junctional)

Can progress to slightly elevated soft papule w/ relatively smooth surface, tan to brown (less pigment) -- (compound)

Progress to rough, papillomatous, sometimes w/ hair, less pigment (intradermal)

Many involute and disappear in latera adulthood

Intraoral nevi much less common than skin

Found on palate, mucobuccal fold, gingiva

Same appearance and evolutionary dev as skin but do not have papillary phase

2/3 in F' 20% non-pigmented av age 35 y/o

Most common IO nevi: intramucosal, blue

Most common on dorsa of hands and feet, scalp and face as macular or dome-shapde blue or blue-black lesion <1 cm in diam

Intraorally almost always on palate

Elongated, slender melanocytes w/ branching dendritic extensions and melanin globules, deep in dermis or lamina propria and parallel to surface

Solitary acquired nevi on skin if long history of presence unchanged, a well-circumscribed lesion & homogenous appearance, don't need to be treated

Departure from above mandates removal and submission for histopathologic exam to rule our melanoma

Any solitary pigmented lesion of oral mucosa should have excisional biopsy and hist exam

Benign but morphologically altered tissue that has a greater than normal risk of malignant transformation

Microscopic reflection: epithelial dysplasia

Chronic reflection: leukoplakia, erythroplakia

Definition of epithelial dysplasia

Enlarged nuclei & cells, large & prominent nucleoli, increased nuclear-to-cytoplasmic ratio, hyperchromatic nuclei, pleomorphic nuclei & cells, dyskeratosis & individual cell keratinization, increased mitotic activity, abnormal mitotic figures

Bulbous or teardrop-shaped rete ridges

Loss of polarity

Keratin or epithelial pearls

Loss of typical epithelial cell cohesiveness

Excessive tissue or other material overlying a normal fibrovascular base (thickening of surface epi, excessive keratin, candida, fibrin)

Normal surface mucosa overlying a hypovascular CT base (scar)

White patch or plaque that cannot be characterized clinically or pathologically as any other disease

(Clinical term which denotes clinical appearance and excludes specific conditions but is not a diagnostic term in and of itself, it implies neither malignancy or benignity - but it does imply increased risk)

Excludes linea alba, leukoedema, lichen planus, candidiasis, frictional keratosis, etc.