Melanoma

by | Nov 26, 2017

General overview of important facts to remember about melanoma

 

Types of Melanoma

  • Lentigo maligna (hutchison melanotic freckle) (8%)
  • Superficial spreading melanoma (70%)
  • Nodular melanoma (20%)
  • Acral lentiginous melanoma (2%)
  • Desmoplastic melanoma
  • Small melanoma
  • Amelanotic melanoma

Pigmented Skin Lesions

  • Melanoma Pathology
  • 30% arise in existing moles
  • 70% arise in normal skin

Risk Factors for Melanoma

  • History of previous melanoma (5x)
  • Male
  • More than 50 moles
  • Family history
  • History of many sunburns
  • Sunsensitive skin/fair complexions
  • Tanning treatments

Red Flags for Melanoma

  • New or changing lesion
  • Rapidly growing nodule
  • Non healing lump or ulcer
  • Ugly duckling syndrome
  • Lesion that concerns patient
  • Dermoscpic changes on follow up
  • Poor dermoscope/clincial correlation

Features of Melanoma

  • ABCDEFG (elevated, firm, growing)
  • Change
  • Bleeding
  • Itching
  • Change in size
  • Change in shape
  • Change in colour
  • Change in surface
  • Change in borded
  • Lymphadenopathy

Differentials of melanoma

  • Haemangioma
  • Dermatofibroma
  • Pigmented Seb K
  • Pigmented BCC
  • Junctional naevi
  • Compound naevi
  • Blue naevi
  • Dysplastic naevi
  • Lentiges

Determinants of Prognosis of Melanoma

  • Thickness (Breslow)
  • Level or depth
  • Site (worse on head and neck)
  • Sex (worse for men)
  • Age

Clark Levels of Melanoma

  • Clark 1, 0
  • Clark 2 , < 0.75mm, 95% 5 year survival
  • Clark 3 – 0.76-1.5 – 70-98% survival
  • Clark 4, 1.51 – 4.0 – 55-85% 5 year survival
  • Clark 5, > 4.0mm, 30-60% 5 year survival

Margins of Melanoma Excision

  • Suspected melanoma = 2mm
  • Mel in situ  = 5mm
  • <1mm thick = 1cm
  • 1-4mm thick = 1-2cm

Follow Up of Melanoma

  • <1mm = 6 monthly for 2 years
  • 1-2mm 4 monthly for 2 years, 6 monthly for 2 years, yearly for 10 years
  • 2mm regular specalist and GP reiew for 10 years
  • Yearly CXR

ABCDEFG Features of Melanoma

  • A – Melenoma is asymmetrical
  • B – Border is well demarcated and irregular
  • C- blue/blac or variety of colours
  • E – Elevation indicates invasion
  • F – Firm
  • G – growing

Practice Tips

  • Excise melaonma with 2mm margins
  • Wider local eccision based on breslow
  • Sentinel lymph node biopsy for tumours > 1mm