skin cancer

Question 1

define a basal cell carcinoma (BCC)

Answer 1

a slow-growing, locally invasive malignant tumour of the epidermal keratinocytes

normally in older pts, rarely metastasises
most common malignant skin tumour

Question 2

what are the causes of a BCC?

Answer 2

risk factors:

1) UV exposure
2) history of frequent or severe sunburn in childhood
3) skin type 1
4) older age
5) male
6) immunosuppression
7) previous hx of skin cancer
8) genetic predisposition

Question 3

how does a BCC present?

Answer 3

nodular BCC small, skin-coloured papule/nodule 
  - with surface telangiectasia
  - pearly rolled edge 
  - leison may have necrotic or  
    ulcerated centre (rodent ulcer)
  - commonly over head+ neck

various morphological types :

1) nodular most common
2) superficial (plaque-like)
3) cystic
4) morphemic (sclerosing)
5) keratotic
6) pigmented

Question 4

what is BCC management?

Answer 4

1) surgical excision (histological exam + tumour margins)
2) mohs micrographic surgery for high-risk recurrent.
3) radiotherapy
4) other- cryotherapy, curetttage + cautery, topical photodynamic therapy, topic treatment eg imiquimod cream for small and low-risk lesion

Question 5

what are the complications of a BCC?

Answer 5

local tissue invasion + destruction

Question 6

what is the prognosis of a BCC?

Answer 6

depends on tumour size, site, type, growth pattern/histological subtype
failure of previous treatment/recurrence and immunosuppression

Question 7

define a squamous cell carcinoma (SCC)?

Answer 7

a locally invasive malignant tumour of the epidermal keratinocytes or its appendages
has potential to metastasise

Question 8

what are the causes of an SCC?

Answer 8

1) excessive UV exposure
2) pre-malignant skin conditions eg actinic keratoses
3) chronic inflammation eg leg ulcers, wound scars
4) immunosuppression
5) genetic predisposition

Question 9

how does an SCC present?

Answer 9

keratotic eg scaly, crusty

ill-defined nodule which may ulcerate

Question 10

what is SCC management?

Answer 10

1) surgical excision
2) mohs micrographic surgery- ill-defined, large, recurrent tumours
3) radiotherapy- large, non-resectable tumours

Question 11

what is the prognosis of an SCC?

Answer 11

depends on tumour size, site, histological pattern, depth of invasion, perineural involvement and immunosuppression

Question 12

define a malignant melanoma

Answer 12

an inasive malignant tumour of the epidermal melanocytes which has the potential to metastasise

Question 13

what are the causes of a melanoma?

Answer 13

1) excessive UV exposure
2) skin type 1
3) history of multiple moles or atypical moles
4) FH or PMH of melanoma

Question 14

how does a melanoma present?

Answer 14

ABCDE symptoms- suspicious features

asymmmetrical shape
border irregularity 
colour irregularity 
diameter >6mm
evolution of lesion (change in size/shape)
symptoms- bleeding, itching

more common on legs (women), trunk (men)

Question 15

what are the types of melanoma?

Answer 15

1) superficial spreading melanoma- legs
2) nodular melanoma- trunk
3) lentigo maligna melanoma- face
4) acral lentiginous melanoma- palms, soles, nail beds

Question 16

what is the management of a melanoma?

Answer 16

1) surgical excision
2) radiotherapy
3) chemotherapy- metastatic

Question 17

what is the prognosis of melanoma?

Answer 17

recurrence of melanoma based on Breslow thickness
<0.76mm low risk, 0.76-1.5mm medium, >1.5mm high risk

5yr survival based on TNM classification
stage 1- 90%, 2 80%, 3 50%, 4 20-30%