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Robert Cawley, D.O.

May 17, 2000 1:00 PM

Melanocytic Tumors of Skin

  1. Benign Melanocytic Tumors of Skin
    1. Lentigo
      1. melanocytic Hyperplasia along rete pegs with hyperpigmentation of basal layer
      2. Occur most commonly in young but may affect all ages.
      3. Small pigmented macules (5-10mm)
    2. Nevocellular Nevus
      1. Congenital or Acquired Neoplasm of melanocytes
      2. Well circumscribed pink-tan-brown uniformly pigmented lesions
      3. May be macular or papular
      4. Types. -
        1. Junctional
        2. Compound
        3. Dermal
      5. Subtypes:
        1. Blue nevus
        2. Spitz nevus
        3. Halo nevus
  2. Pre-Malignant Nevi
    1. "Dysplastic Nevus" DOES IT EXIST?
      1. Larger than acquired nevi
      2. Irregular contours
      3. Variable pigmentation
      4. Sporadic vs. Syndromic
        1. Heritable Melanoma syndrome
          1. Autosomal dominant inheritance
          2. Dysplastic nevi in patient with at least 2 close relatives with melanoma
          3. lifetime risk-56% (sporadic-10%)
      5. malignant transformation may occur
      6. Pathology
        1. Cytologic atypia
        2. Architectural atypia

     

     

     

     

     

     

  3. Malignant Melanocytic Tumors - Malignant Melanoma
    1. Common Tumor with increasing incidence
    2. Sunlight is of primary importance as an etiologic factor but is not required for its development.
    3. Location
      1. Men- back
      2. Women - back and legs
      3. Face
      4. Anogenital skin/ mucosa, oral mucosa, choroid of the eye, meninges, esophagus.
    4. Clinical appearance
      1. May be asymptomatic or pruritic
      2. Recent change in color, size, elevation, bleeding, ulceration, circumscription.
    5. Pathologic types
      1. Superificial spreading 50 - 75%
      2. Lentigo maligna melanoma 5 - 15%
      3. Nodular Melanoma 15 -35%
      4. Acral lentiginous 5 -10%
      5. Others
        1. In situ melanoma
        2. Desmoplastic/Neurotropic
    6. Prognostication
      1. Clarks levels I-V
      2. Breslow's Depth
      3. Vertical growth phase vs. Radial growth
      4. Mitotic rate
      5. Lymphocytic response
      6. Regression
      7. Satellite nodes
      8. Other minor
        1. Sex
        2. Location
    7. Treatment
      1. RGP: 0.5 cm margin
      2. VGP: 2.5 cm margin
      3. Lymph node dissection?
      4. Sentinel nod analysis