2. NEVUS:
A benign, exophytic, usually pigmented,
congenital lesion of the skin or mucosa
composed of focal collections of rounded
melanocytes (nevus cells).
• The term nevus commonly used for
mole.
• Nevi mostly occur on skin, occasionally
occur on mucous membrane.
• Its also called birthmark.
3. Classification:
• Intradermal (mucosal)
• Junctional
• Compound
• Macular form also called Blue
nevus
• Epithelioid or Spitz
6. CLINICAL FEATURES:
• The lesion grows slowly.
• It is generally less then 1 cm in
diameter.
• Intradermal nevus occurs in young
patients and is one of common skin
lesions.
On skin it is raised or flat.
It is tan or dark brown.
It will often contain more hair than
surrounding normal skin.
7. • Intramucosal nevus occurs in oral
cavity mostly on the Hard palate or
Gingiva.
Its an asymptomatic.
Pigmented.
Brown to black.
Slighted elevated papule or flat
macule.
8. HISTOPATHOLOGY:
• It is characterized by nests, cords or
sheets of nevus cell confined to
connective tissue.
• Cells of nevus may be epithelioid,
lymphocyte like, spindle or
multinucleated types.
• Mitotic figures are usually absent.
• One of features of nevus is
presence of fibrous connective
tissue zone which separates it from
overlying epithelium.
9.
10. TREATMENT:
As a general rule all solitary
pigmented papules or nodules of
the oral cavity should be excised.
Once excised nevi do not tend to
recur.
12. CLINICAL FEATURES:
• It is benign.
• Brown to black lesion.
• Occurs primarily on the skin and
occasionally on oral mucosa.
• Within oral cavity it usually
appears as a pigmented macular
lesion on the hard palate or
gingiva.
13. HISTOPATHOLOGY:
• It is characterized by the presence of
nevus cell nests in the basilar region of
epithelium.
• No nevus cells found in surround
connective tissue.
• Careful examination is required
because similar type of focal
proliferation of melanocytes
(junctional cavity) occurs in melanoma.
• It is important to note it can transform
to malignant melanoma.
14.
15. TREATMENT:
It should be excised and submitted to
histopathological examination. Once
excised, a junctional nevus does not
tend to recur.
17. • It has the combined
characteristics of the
intramucosal nevus and
junctional nevus.
• Exhibiting nevus cells in the
basal region of the epithelium
and the adjacent connective
tissue.
18. CLINICAL FEATURES:
• Compound nevus is far more
common then other nevi.
• In oral cavity it tends to occur as
pigmented papule or macule.
• It occurs on hard palate or
gingiva.
TREATMENT:
The nevus is treated by an
excisional biopsy that serves as a
diagnostic and therapeutic
procedure.
20. CLINICAL FEATURES:
• The blue nevus in benign pigmented
lesion that presents as a dark blue
dome-shaped papule or as a flat
macule on the skin or mucosa.
• It occurs most commonly on the hard
palate.
21. HISTOPATHOLOGY:
• In blue nevus pigment-producing
cells are spindled and fusiform
dendritic cells.
• Cells are confined to the connective
tissue.
• They are separated and parallel to
the normal overlying epithelium.
• Macrophages often present among
dendritic cells.
• They have no tendency to transform
into malignant lesion.
25. • It is also called Spitz nevus and
formerly called a “benign juvenile
melanoma.
CLINICAL FEATURES:
• It presents as a solitary small pink to
reddish-brown papule.
• It occurs on skin of face and
extremities of children.
26. HISTOPATHOLOGY:
• It is usually composed of spindle
shaped and large epithelioid nevus
cells with abundant cytoplasm.
• It is relatively circumscribed nests
located at or near dermal and
epidermal interface.
• It is multinucleated.
• Its size is 5 to 6 mm in diameter.
