Basal cell carcinoma

Question 1

What is basal cell carcinoma?

Answer 1

Basal cell carcinoma, also known as rodent ulcer, is a malignancy of basal keratinocytes

Question 2

Who are basal cell carcinomas more common in?

Answer 2

UK - Middle age and elderly
Australia - Younger age groups

Question 3

Describe the histopathology of basal cell carcinoma

Answer 3

• Basal cells sprout from epidermis
• Groups of cells invade dermis
• Peripheral palisading
• Mitoses and apoptoses very numerous
• Prominent desmoplastic fibrous stroma
• Margins are poorly defined

Question 4

Describe the growth of BCC

Answer 4

Slow growing and only locally destructive with very little risk of metastasis
May spread along nerves (Perineural invasion)

Question 5

How will BCC present?

Answer 5

This will usually present with a slow growing lesions with a rolled pearly edge and central ulceration that “just won’t heal”

There may also be presence of telangiectasia (Visible thread-like blood vessels)

It will usually be shinier than the surrounding skin

They will be often asymptomatic

Question 6

What are the 3 main types of BCC?

Answer 6

• Nodular
• Superficial
• Infiltrative

Question 7

What are some conditions that increase risk of basal cell carcinoma?

Answer 7

Xeroderma pigmentosum
Oculocutaneous albinism

Question 8

What is oculocutaneous albinism?

Answer 8

An autosomal recessive absence/defect of tyrosinase resulting in absence of melanin

Question 9

What are the 6 main pathways of BCC formation?

Answer 9

1. Epidermal keratinocyte DNA damanged by solar UV radiation
2. Mutation of tumour suppressor genes and loss of apoptotic function
3. Mutation of protooncogenes
4. Clonal selection of non-apoptosing, mutated cells
5. Solar UV suppresses normal cell mediated immune response agaisnt tumour cells
6. Further growth to macroscopic tumour

Question 10

What is meant by nodular BCC?

Answer 10

• Slow-growing, shiny, pearly nodule with superficial telangiectasia
• Commonly on the face
• May be ulcerated (‘rodent ulcer’)

Question 11

What is meant by superficial BCC?

Answer 11

• Erythematous well-demarcated scaly plaques, often larger than 20 mm at presentation
• Slightly raised ‘whipcord’ margin
• Slow growth over months or years

Question 12

What is meant by infiltrative BCC?

Answer 12

• Characterised by thickened yellowish plaques
• May infiltrate tissues widely; may spread along nerves
• Margins poorly defined

Question 13

What condition is shown?

Answer 13

Nodular BCC - Rolled, pearly edge and central ulceration

Question 14

What condition is shown?

Answer 14

Nodular BCC

Question 15

What condition is shown?

Answer 15

Infiltrative BCC - Telangiectasia, pearly surface

Question 16

What condition is shown?

Answer 16

Superficial BCC - Flattened and well defined, will follow typical history of non-healing, will often just show superficial erosions

Question 17

What condition is shown?

Answer 17

Superficial BCC

Question 18

How are nodular BCCs treated?

Answer 18

Basic excision 3-4mm around the edge

Question 19

How is infiltrative BCC treated?

Answer 19

Mohs surgery (Wider excision with pathology to check if all excised there and then - Small nicks taken from the skin around the edge of the previous excision which are colour coded and passed under the microscope

Question 20

How is superficial BCC treated?

Answer 20

Using either freezing with liquid nitrogen or topical treatment with cytotoxic cream (Efudix) or immunostimulant cream (Imiquimod)

Question 21

How can neglected, advanced BCC be treated?

Answer 21

Radiotherapy