II. Epidemiology

  1. Onset after age 6-12 months, and forming new nevi until age 50 years, when they begin the recede
  2. Common Incidence in Caucasian skin
    1. Typical Caucasian adults have 20 nevi (some adults may have 40-50)
    2. Most concentrated on sun exposed areas
  3. Less numerous in pigmented skin (e.g. Black)

III. Physiology

  1. Melanocytes
    1. Melanin producing cells in the Stratum Basale (bottom layer) of the Epidermis
    2. Contributes to overall skin, hair, eye pigmentation
  2. Nevus Cells
    1. A type of Melanocyte that is larger and is without Dendrites
    2. Nevus cells form nests at the dermal-epidermal junction
  3. Nevus cells mature from Type A to Type C cells and migrate downward from Epidermis to Dermis
    1. Type A Nevus Cell: Epitheloid (epidermal)
    2. Type B Nevus Cell: Lymphocytoid
    3. Type C Nevus Cell: Neuroid (dermal)

IV. Classification: Nevi

  1. Over decades, moles descend into the Dermis and progress from Junctional Nevi to Compound Nevi and then to dermal nevi
  2. Junctional Melanocytic Nevus
    1. Flat to slightly elevated nevi with sharp borderss, and typically hairless
    2. Uniformly tan, brown or black nevi starting at 1-2 mm and expanding to 4-6 mm
    3. Localized at the dermoepidermal junction
  3. Compound Melanocytic Nevus
    1. Slightly elevated to dome shaped Papule
    2. Flesh or brown colored nevi
    3. May have hypopigmented surrounding ring known as Halo Nevus
    4. Start at the dermal-epidermal junction and extend into the Dermis
  4. Dermal Melanocytic Nevus
    1. Dome shaped nevi which may have a verrucous, pedunculated or polypoid surface
      1. Elevation off skin predisposes to local Trauma, irritation and bleeding
      2. Distinguish from nodular Melanoma which may have a similar appearance
    2. Nevi may be flesh colored or pink to brown or black, diameter may approach 1 cm
    3. Localized to the Dermis
    4. Degeneration into Melanoma is rare

V. Signs

  1. General characteristics
    1. Small (< 1 cm)
    2. Sharply circumscribed
    3. Soft, round or oval Macules or dome shaped Papules
  2. Junctional Nevus Characteristics
    1. Minimally raised Papule or flat Macule
    2. Smooth regular borders
    3. Tan, brown or dark brown color
    4. Distribution
      1. Palms and soles
      2. Trunk
      3. Face
      4. Upper extremities
      5. Lower extremities
  3. Dermal Nevus
    1. Skin-colored, tan or brown colored Papules
    2. Round, dome-shaped, well circumscribed Papules
    3. Distribution
      1. Most common: Face and neck
      2. Other locations: Trunk, extremities

VI. Differential Diagnosis

  1. Junctional Nevus larger than 1 cm
    1. Congenital Nevus
    2. Dysplastic Nevus
  2. Dermal Nevus
    1. Basal Cell Carcinoma
    2. Dysplastic Nevus

VII. Management

VIII. References

  1. Habif (2003) Clinical Dermatology, 4th ed.. Mosby, p. 773-813

Images: Related links to external sites (from Bing)

Related Studies

Ontology: Nevus (C0027960)

Definition (MEDLINEPLUS)

Moles are growths on the skin. They happen when pigment cells in the skin, called melanocytes, grow in clusters. Moles are very common. Most people have between 10 and 40 moles. A person may develop new moles from time to time, usually until about age 40. In older people, they tend to fade away.

Moles are usually pink, tan or brown. They can be flat or raised. They are usually round or oval and no larger than a pencil eraser.

About one out of every ten people has at least one unusual (or atypical) mole that looks different from an ordinary mole. They are called dysplastic nevi. They may be more likely than ordinary moles to develop into melanoma, a type of skin cancer. You should have a health care professional check your moles if they look unusual, grow larger, change in color or outline, or in any other way.

NIH: National Cancer Institute

Definition (CSP) circumscribed stable malformation of the skin and occasionally of the oral mucosa, which is not due to external causes.
Definition (MSH) A circumscribed stable malformation of the skin and occasionally of the oral mucosa, which is not due to external causes and therefore presumed to be of hereditary origin.
Concepts Neoplastic Process (T191)
MSH D009506
ICD10 D22
SnomedCT 247456007, 189051001, 109265005, 51697005, 21119008
English Mole, Nevi, NAEVUS, NEVUS, Mole, Skin, Skin Mole, Moles, Skin, Skin Moles, nevus NOS, Nevus [Disease/Finding], mole, nevi, Moles, Nevus (disorder), Skin mole, nevus, Naevus, NOS, Nevus, NOS, Skin mole, NOS, Nevus, naevus, Naevus, Mole of skin
French NAEVUS, Grain de beauté, Grains de beauté, Naevus
Dutch naevus, huidmoedervlek, Naevus
German Naevus, Hautmal, MUTTERMAL, Muttermal, Nävus
Italian Mola cutanea, Nevo
Portuguese Nevo cutâneo, Nevo Epidérmico, NEVUS, Sinais da Pele, Sinal da Pele, Manchas da Pele, Pintas da Pele, Nevo
Spanish Lunar, Nevo Epidérmico, NEVUS, Señal de la Piel, Señales de la Piel, nevus, nevo (trastorno), nevo, Lunares de la Piel, Nevus, Manchas de la Piel, Nevo
Japanese 色素性母斑, シキソセイボハン, ボハン, 母斑
Swedish Leverfläck
Czech névus, Névus, Kožní mateřské znaménko, mateřské znaménko, névy
Finnish Luomi
Croatian MADEŽ
Polish Znamię
Hungarian Naevus, Bőr molája
Norwegian Nevus, Føflekker

Ontology: Melanocytic nevus (C0027962)

Definition (MSH) A nevus containing melanin. The term is usually restricted to nevocytic nevi (round or oval collections of melanin-containing nevus cells occurring at the dermoepidermal junction of the skin or in the dermis proper) or moles, but may be applied to other pigmented nevi.
Definition (NCI) A neoplasm composed of melanocytes that usually appears as a dark spot on the skin.
Definition (NCI_NCI-GLOSS) A benign (not cancer) growth on the skin that is formed by a cluster of melanocytes (cells that make a substance called melanin, which gives color to skin and eyes). A mole is usually dark and may be raised from the skin.
Concepts Neoplastic Process (T191)
MSH D009508
ICD10 D22.9 , D22, M8720/0
SnomedCT 21119008, 190213002, 189051001, 189096008, 400096001
English Nevus, Pigmented, Nevi, Melanocytic, Nevi, Pigmented, Nevus, Melanocytic, Melanocytic Nevi, Pigmented Nevi, NAEVI MELANOCYTIC, NAEVI PIGMENTED, NEVI MELANOCYTIC, NEVI PIGMENTED, Pigmented Nevus, Melanocytic naevi, unspecif, Melanocytic naevi, unspecified, Melanocytic nevi, unspecif, Melanocytic nevi, unspecified, [X]Melanocytic naevi, unspecif, [X]Melanocytic naevi, unspecified, [X]Melanocytic nevi, unspecif, [X]Melanocytic nevi, unspecified, Melanocytic naevi, Nevi melanocytic, Nevi pigmented, [M]Pigmented naevus NOS, [M]Pigmented nevus NOS, Pigmented naevus NOS, Pigmented nevus NOS, Pigmented nevus, no ICD-O subtype, Naevi melanocytic, Nevus melanotic, Melanocytic nevi, Nevus, Pigmented [Disease/Finding], melanocytic naevus, pigmented nevi, melanocytic nevi, melanocytic nevus, pigmented mole, Naevus;pigmented, melanocytic naevi, mole, moles, Pigmented Moles, [X]Melanocytic nevi, unspecified (disorder), [X]Melanocytic naevi, unspecified (disorder), Naevus melanotic, Pigmented nevus, no International Classification of Diseases for Oncology subtype (morphologic abnormality), Pigmented nevus, no International Classification of Diseases for Oncology subtype, Pigmented nevus, no ICD-O subtype (morphologic abnormality), Pigmented nevus, Mole, Nevus, Melanocytic naevus, Naevus, Pigmented naevus, Melanocytic nevus (disorder), Pigmented nevus, NOS, Melanocytic nevus, Pigmented nevus (morphologic abnormality), Melanocytic Nevus, Melanotic Nevus, Mole of Skin, pigmented nevus, Nevus;pigmented, pigmented naevus, Naevi pigmented, Nervus pigmented
French NAEVUS PIGMENTAIRE, Nerf pigmenté, Naevus mélanique, MELANOME BENIGNE, Naevus mélanocytique, Naevus pigmentaire, Naevus mélanocytaire, Naevus pigmentaires
Portuguese NEVO PIGMENTADO, NEVO MELANOCITICO, Nevo pigmentar, Nevo pigmentado, Nevo melanótico, Nevo melanocítico, Nevo Melanocítico, Nevo Pigmentado
Spanish nevo pigmentado, no clasificado como subtipo en CIE-O, Nevus pigmentado, nevo pigmentado (anomalía morfológica), NEVUS MELANOCITICO, NEVUS PIGMENTADO, Nevus melanótico, Nevus melanocítico, Nevus pigmentario, nevus melanocítico, no especificado, nevo melanocítico, no especificado, nevo melanocítico, no especificado (trastorno), nevo pigmentado, no clasificado como subtipo en CIE-O (anomalía morfológica), nevo melanocítico (trastorno), nevo melanocítico, nevo pigmentado, nevus melanocítico, nevo, nevus, Nevo Melanocítico, Nevo Pigmentado
Dutch gepigmenteerde naevi, melanocytische naevi, gepigmenteerde naevus, Melanocytaire naevi, niet gespecificeerd, melanocytische naevus, Melanocytaire naevi, Gepigmenteerde naevus, Halonaevus, Melanocytaire naevus, Naevus, gepigmenteerde
German Pigmentnaevus, Naevi pigmentiert, pigmentierter Naevus, melanozytische Naevi, Nevus melanotisch, Naevis pigmentiert, LEBERFLECKEN, Melanozytennaevus, nicht naeher bezeichnet, Melanozytennaevus, NAEVI PIGMENTIERT, melanozytischer Naevus, Naevus pigmentosus, Halonävus, Melanozytennävus, Nävus, melanozytärer, Pigmentnävus, Sutton-Nävus
Japanese メラノサイト性母斑, メラノサイトセイボハン, シキソセイボハン, 黒色細胞母斑, 母斑-色素性, コクショクボハン, 黒色母斑, 母斑細胞母斑, 色素性母斑, 色素細胞母斑, 母斑-黒色細胞
Swedish Pigmentnevus
Czech névus pigmentový, Névy melanocytické, Melanocytický névus, Névy pigmentové, Névus pigmentový, Névus melanocytický, Pigmentový névus
Finnish Pigmenttiluomi
Italian Nevi melanocitici, Nevo ad alone, Nevo melanocitico, Nevi ad alone, Nevi pigmentati, Nevo pigmentato
Korean 색소 세포성 모반, 상세불명의 색소 세포성 모반
Polish Znamię barwnikowe
Hungarian Pigmentált nervus, Melanocytás naevus, Festékes anyajegy, Festékes naevus, Pigmentált naevus, Melanocytás anyajegy, Pigmentsejtes anyajegy, Melanoticus naevus
Norwegian Pigmentert nevus

Ontology: Nevus, Intradermal (C0206737)

Definition (NCI) A nevus characterized by the proliferation of nevus cells in the dermis without involvement of the dermal-epidermal junction.
Definition (MSH) A nevus in which nests of melanocytes are found in the dermis, but not at the epidermal-dermal junction. Benign pigmented nevi in adults are most commonly intradermal. (Stedman, 25th ed)
Concepts Neoplastic Process (T191)
MSH D018330
ICD10 M8750/0
SnomedCT 112681002, 302838006
English Nevi, Intradermal, Nevus, Intradermal, Intradermal Nevi, Nevus, Intradermal [Disease/Finding], dermal nevus, intradermal nevus, Naevus;intradermal, intradermal nevi, intradermal melanocytic nevus, Intradermal nevus, Dermal nevus, Cellular naevus, Cellular nevus, Dermal cellular naevus, Dermal cellular nevus, Dermal naevus, IDN - Intradermal naevus, IDN - Intradermal nevus, Intradermal melanocytic naevus, Intradermal melanocytic nevus, Intradermal naevus, Dermal cellular nevus (disorder), Intradermal nevus (morphologic abnormality), Intradermal Nevus, Dermal Nevus, Nevus;intradermal, intradermal naevus
Dutch intradermale naevus, Intradermale naevus, Naevus, intradermale
French Naevus intra-dermal, Naevus intradermique, Naevus intradermiques
German intradermaler Naevus, Intradermalnaevus, Nävus, intradermaler
Portuguese Nevo intradermal, Nevo interdermal, Nevo Intradérmico
Spanish Nevus intradérmico, nevo celular dérmico (trastorno), nevo celular dérmico, nevo dérmico, nevo intradérmico (anomalía morfológica), nevo intradérmico, Nevo Intradérmico
Swedish Nevus, intradermal
Japanese シンピナイボハン, 母斑-真皮内, 休止性母斑, 真皮内母斑
Czech névus intradermální, Intradermální névus
Finnish Verinahkaluomi
Italian Nevi intradermici, Nevo intradermico
Polish Znamię barwnikowe śródskórne
Hungarian Intradermalis naevus, Naevus intradermalis
Norwegian Intradermal nevus

Ontology: Compound nevus of skin (C0259781)

Definition (NCI_NCI-GLOSS) A type of mole formed by groups of nevus cells found in the epidermis and dermis (the two main layers of tissue that make up the skin).
Definition (NCI) A nevus composed of neoplastic melanocytes that infiltrate both the epidermis and the dermis.
Concepts Neoplastic Process (T191)
ICD10 M8760/0
SnomedCT 49409001, 254805008
Dutch compound naevus
French Naevus mixte
German Compound-Naevus
Italian Nevo composto
Portuguese Nevo composto
Spanish Nevus compuesto, nevo compuesto (anomalía morfológica), nevo compuesto, nevo cutáneo compuesto (trastorno), nevo cutáneo compuesto, nevo dermoepidérmico
Japanese 複合母斑, フクゴウボハン
English compound nevus, compound nevus (diagnosis), nevus compound, Naevus;compound, Compound nevus, Dermal and epidermal nevus, Compound naevus, Compound naevus of skin, Compound nevus of skin, Dermal and epidermal naevus, Compound nevus (morphologic abnormality), Compound nevus of skin (disorder), Compound Nevus of Skin, Compound Nevus of the Skin, Compound Nevus, Nevus;compound, compound naevus
Czech Smíšený névus
Hungarian Vegyület naevus, Vegyület anyajegy

Ontology: Junctional nevus (C0334433)

Definition (NCI_NCI-GLOSS) A type of nevus (mole) found at the junction (border) between the epidermis (outer) and the dermis (inner) layers of the skin. These moles may be colored and slightly raised.
Definition (NCI) A nevus characterized by the presence of an intraepidermal proliferation of nevus cells. The nevus cells form multiple nests in the dermal-epidermal junction. It presents as a small, slightly raised, pigmented skin lesion.
Concepts Neoplastic Process (T191)
ICD10 M8740/0
SnomedCT 254802006, 30494009
English Junction melanocyt naevus skin, Junction melanocyt nevus skin, Junctional naevus NOS, Junctional nevus NOS, junction nevus, Naevus;junctional, junctional melanocytic nevus, junctional nevus, Intra-epidermal naevus of skin, Intra-epidermal nevus of skin, Intraepidermal naevus, Intraepidermal nevus, Junction naevus, Junction nevus, Junctional melanocytic naevus, Junctional melanocytic naevus of skin, Junctional melanocytic nevus, Junctional melanocytic nevus of skin, Junctional melanocytoma, Junctional naevus, Junctional nevus, Junctional melanocytic nevus of skin (disorder), Junctional nevus (morphologic abnormality), Junctional nevus, NOS, Intraepidermal Nevus of Skin, Intraepidermal Nevus of the Skin, Intraepidermal Nevus, Junction Nevus, Junctional Melanocytic Nevus, Junctional Melanocytoma, Junctional Nevus of Skin, Junctional Nevus of the Skin, Junctional Nevus, Junctional Skin Nevus, Nevus;junctional, junctional naevus
Dutch junction naevus
French Naevus jonctionnel, Naevus de la zone de jonction
German junktionaler Naevus, Junktionsnaevus
Italian Nevo giunzionale
Portuguese Nevo de junção, Nevo da junção dermoepidérmica
Spanish Nevus juncional, Nevus de transición, melanocitoma de la unión dermoepidérmica, nevo de la unión dermoepidérmica (anomalía morfológica), nevo de la unión dermoepidérmica, nevo de la unión, nevo intraepidérmico de la piel, nevo intraepidérmico, nevo melanocítico de la unión dermoepidérmica de la piel (trastorno), nevo melanocítico de la unión dermoepidérmica de la piel
Japanese 接合部母斑, セツゴウブボハン
Czech Junkční névus
Hungarian Junctionalis nevus, Junctionalis naevus