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Skin Lesion History #1

PATIENT INFORMATION

Peter is a 73-year-old Caucasian male who presents to the GP with a skin lesion. You are a medical student at the GP clinic, and have been asked to see him prior to his consultation.

PMHx

Actinic keratosis, HTN

Mx

Perindopril; NKDA

CANDIDATE INSTRUCTIONS

You will have 9 minutes to perform the following:

  1. Take a focused history from Peter regarding his presenting complaint. You may ask to look at the picture of the skin lesion. (7 minutes)
  2. Answer two questions related to Peter’s presentation. (2 minutes)

TASK 1 – HISTORY (7 MINUTES)

Aboriginal/Torres Strait Islander

No

Opening statement

“Hey Doc, I seem to be getting these rashes again and I am worried I could have a melanoma like my dad!”

  • If asked to elaborate: “Well, last time I had some pre-cancerous lesions removed so I don’t know if this is cancer. What do you think?”

HOPC

  • Site: On the R) ear (point to middle of helix)
    • If asked: Unsure of other sites
  • Quality: (what does it look like/feel like/do?)
    • Appearance: Looks red
    • Height: Fairly flat
    • Texture: Feels like sandpaper – hard/scaly
    • Itch: Nil
    • Pain: Sometimes feels like it’s burning, doesn’t hurt to touch
    • Bleeding/ulceration: Nil
  • Severity: (worried about appearance?)
    • How it looks doesn’t bother me, I’m more worried it could be a cancer
  • Time course:
    • Onset: Unsure, but my wife did say something about a rash on my ear about a year ago… all I know is it wasn’t there when I last saw the dermatologist a few years ago!
    • Pattern/Progression: I don’t think it’s gotten bigger… otherwise my wife would’ve nagged me more!
    • Previous episodes: The dermatologist removed some skin from my hand and said it was pre-cancerous. He said I was at risk of skin cancer and to come back, but it’s hard since we live rurally and can’t afford it.
  • Exacerbating/relieving factors: Nil

Context/associated features

  • 2 marks for asking ≥3 context questions
  • + 3 marks for asking 3 associated features+ 2 marks for asking 2 associated features, etc.

Symptoms in BOLD indicate positive answers, other answers are suggestions of what to ask.

Context

  • Sun exposure:
    • Worked in construction outdoors for 30+ years
    • Now retired, but continues to work outdoors on farm
    • Spent lots of time outdoors surfing/swimming
    • Did not use sun protection and still doesn’t
    • Experienced sunburn on multiple occasions, including skin blistering
    • Nil use of sunbeds
  • Pale skin – blonde hair, blue eyes
  • Born and raised in Australia
  • FHx skin Ca – mum had 2x SCC, dad had melanoma
  • Nil PMHx immunosuppression/Ca

Associated features

  • Actinic Keratosis (AK): sun-damaged skin, yellow/brown, reddish tinge, rough like sandpaper
  • Bowen’s Disease: may appear similar to AK but can change over time
  • SCC: sun-damaged skin, can bleed/ulcerate
    • variable appearance – can be large, fleshy, granulomatous, or firm or hard
  • BCC: mainly on head and neck, slow-growing, erodes with minimal trauma; pearly, smooth & firm with telangiectasia
  • Psoriasis: well-defined pink plaques with silvery scales, itchy; widespread on scalp & extensor surfaces

Past medical history

  • Previous AKs on R) hand – treated with topical imiquimod (4ya)
  • HTN – long standing

Medications

  • Perindopril 4mg once daily

Allergies

  • Nil

Family history

  • Mum had 2x SCC removed, died from AMI at 81
  • Dad had 1x melanoma removed, died from pneumonia at 76

Social history

  • Lives with wife in Mildura
  • Independent with all ADLs
  • Feels well supported
  • Ex-smoker – quit at 45yo (smoked 5-10 a day)
  • Nil EtOH or recreational drugs

TASK 2 – QUESTION (1 MINUTE)

What is your top differential diagnosis? (describe the skin lesion in your answer)

Please show the candidate the image below, even if they have already asked to see it during the history:

Actinic keratosis

  • Poorly defined 1-2cm red lesion with superficial scaly appearance
  • Lack of change over time and absence of well-defined borders, extensive hyperkeratosis or tenderness/bleeding/ulceration suggests ?benign
  • However – lesion needs biopsy to confirm diagnosis of AK and rule out more concerning differentials (e.g. Bowen’s, SCC)

TASK 3 – QUESTION (1 MINUTE)

Describe this lesion and what makes it different to the one above.

Please show the candidate the image below:

  • Poorly defined lesion with multicolored yellow and brown crust and evidence of hyperkeratosis
  • Unlike previous lesion – larger, more irregular and has signs of surrounding skin invasion consistent with SCC
Total:

Skin cancers

SCC, BCC and melanoma are the main skin cancers to be familiar with. It can be hard to differentiate BCC and SCC, but have a look at pictures on DermNet and try describing them! Here are a few hints to tell them apart in MCQs:

Basal cell carcinoma

  • Isolated single lesion
  • Only occurs in areas with hair follicles, e.g. head, trunk
    • Danger sites = medial and lateral canthi, nasolabial fold, behind ears
  • Appearance: Pink pearly nodule with central ulceration and raised edges (NB: can also be flat); arborising telangiectasia

Squamous cell carcinoma

  • Occurs in sun-damaged skin – head, chest, back, dorsal hands, shins
  • May be tender/painful
  • Appearance: erythematous/white-pink nodule with central hyperkeratosis, can bleed (friable)/ulcerate, can be tender

Treatments for melanomas and other skin cancers are also good to know.