Please confirm topic selection

Are you sure you want to trigger topic in your Anconeus AI algorithm?

Please confirm action

You are done for today with this topic.

Would you like to start learning session with this topic items scheduled for future?

Updated: May 3 2022

Melanoma

Images
https://upload.medbullets.com/topic/114065/images/melanoma 2.jpg
https://upload.medbullets.com/topic/114065/images/acral_lentiginous_melanoma.jpg
https://upload.medbullets.com/topic/114065/images/nodularmelanoma.jpg
https://upload.medbullets.com/topic/114065/images/lentigomaligna melanoma.jpg
  • Snapshot
    • A 46-year old woman presents to her primary care physician for a dark spot on the back of her right hand. She states that the spot first appeared about 2 years ago and has slowly been growing. It does not burn, itch, or sting. She has a history of regular suntanning and minimal sunscreen use. On exam, there is a 2-cm, asymmetric, thin, brownish-blue plaque with somewhat ill-defined borders and an irregular pattern of coloration.
  • Introduction
    • Overview
      • malignant tumor of melanocytes
        • most commonly affects the skin
          • other sites of involvement
            • brain
            • uvea
            • intestines
            • mucosa
        • melanocytes are of neural crest cell origin
        • 4 types of cutaneous invasive melanoma
          • superficial spreading (most common)
            • usually seen in sunexposed areas
          • nodular (second most common)
            • usually seen in men and often associated with ulceration
          • acral
            • most commonly seen in Asians, Hispanics, and patients from African descent
          • lentigo maligna (invasive melanoma)
            • typically seen in elderly patients
    • Epidemiology
      • incidence
        • most commonly seen between the ages of 40-60
      • risk factors
        • dysplastic nevi
        • multiple nevi
        • ultraviolet radiation exposure
        • fair-skin color
        • immunsuppresion
    • Pathophysiology
      • Clark model of pathogenesis
        • melanocytes proliferate to form a benign nevus
        • genetic mutations (e.g., BRAF) lead to the nevus to become dysplastic (pre-malignant)
          • radial growth → vertical growth
            • can eventually metastasize
          • BRAF mutation
            • seen in ~50% of patients with metastatic cutaneous melanoma
            • secondary to a valine-to-glutamic acid substitution at codone 600 (V600E)
    • Prognosis
      • prognostic favorable
        • favorable
          • localized disease with the tumor being ≤ 1 mm deep
        • negative
          • metastatic disease
  • Presentation
    • Physical exam
      • pigmented skin lesion
        • ABCDEs
          • Asymmetric
          • Border irregularity
          • Color variation
          • Diameter ≥ 6 mm
          • Evolution over time
  • Studies
    • Serum labs
      • S-100 tumor marker
    • Invasive studies
      • excisional biopsy
        • indication
          • preferred biopsy method to confirm the diagnosis
        • findings
          • atypical melanocytes and architectural disorder
            • atypical
              • larger than normal melanocytes
              • large hyperchromatic nuclei
              • irregular nuclear shape
              • abnormal chromatin pattern
            • architectural disorder
              • asymmetry
              • nests of melanocytes of varying sizes and shapes
  • Differential
    • Actinic keratosis
      • differentiating factors
        • secondary to proliferation of atypical epiderminal keratinocytes
        • lesions are small, rough papules that are erythematous or brownish
    • Basal cell carcinoma
      • differentiating factors
        • lesions are waxy, pink, and pearly
          • can have central crusting or ulceration
        • histology demonstrates palisading nuclei
  • Treatment
    • Medical
      • vemurafenib
        • indication
          • BRAF kinase inhibitor that can be considered in patients with metastatic or unresectable melanoma with BRAF V600E mutations
            • typically given with cobimetinib
        • can lead to T cell mediated destruction of malignant melanocyte
    • Surgical
      • wide local excision
        • indication
          • mainstay of treatment for primary cutaneous melanoma
  • Complications
    • Metastatic melanoma
      • lung
      • brain
      • liver
      • bone
      • intestines
Card
1 of 0
Question
1 of 6
Private Note