Sebaceous Cysts (And Other Common Skin Lumps)

Question 1

What are the clinical features of basal cell carcinoma. (7)

Answer 1

Occur in late life. 
Slow growing nodule. 
May ulcerate. 
Pearly edge. 
Telangiectasia. 
Can erode local structures. 
Does not metastasise.

Question 2

What are the clinical features of squamous cell carcinoma. (5)

Answer 2

Rapidly growing.
Nodule which ulcerates.
More common in immunosuppressed patients (renal transplant patients).
Occurs in areas of chronic inflammation.
They can metastasise.

Question 3

What are the features of malignant melanoma. (4)

Answer 3

Can occur in young patients.
Transformation of moles.
Consider in all bleeding pigmented lesions of changing moles.
Early metastasis. .

Question 4

What are moles.

Answer 4

Benign overgrowth of melanocytes that are common in white skinned people.

Question 5

What is a basal cell papilloma. (2)

Answer 5

Seborrhoeic wart.

A common benign overgrowth of the basal cell layer of the epidermis.

Question 6

What is a dermatofibroma (histiocytoma). (6)

Answer 6

They appear as firm, elevated pigmented nodules which may feel like a button in the skin.
A peripheral ring of pigmentation is sometimes seen.
They are often found on the leg and are commoner in females.
There may be a preceding history of trauma or insect bite.
The lesions consists of histiocytes, blood vessels and varying degrees of fibrosis.

Question 7

What is an epidermoid cysts (previously ‘sebaceous cyst’). (3)

Answer 7

Present as cystic swellings of the skin with a central punctum.
They contain ‘cheesy’ keratin.
These cysts occasionally rupture causing significant dermal inflammation.

Question 8

What is a piilar cyst (trichilemmal cyst). (2)

Answer 8

Smooth cysts without a punctum usually found on the scalp.

There may be multiple and familial.

Question 9

What is a keratoacanthoma. (2)

Answer 9

Rapidly growing epidermal tumours which develop central necrosis and ulceration.
Occur on sun-exposed skin in later life and can grow up to 2-3cm.

Question 10

What is pyogenic granuloma (3)

Answer 10

Benign overgrowth of blood vessels.
They present as rapidly growing pinkish red nodules which are friable and readily bleed.
They may follow trauma and are often found on the fingers and lips.

Question 11

What is a cherry angioma (Campbell de Morgan spots).

Answer 11

Benign angiokeratomas that appear as tiny pinpoint red papules.
Occur especially on the trunk and increase with age.

Question 12

What is solar keratosis. (2)

Answer 12

Occur later in life in white skinned people who have had significant sun exposure.
Appear on exposed skin as erythematous silver scaly papules or patches with a conical surface and a red base.

Question 13

What is Bowen’s disease. (2)

Answer 13

A form of intraepidermal carcinoma in situ which rarely can become invasive.
It is thought to be due to long term sun exposure.
Appears commonly on women’s legs and looks like psoriasis but has an irregular edge.

Question 14

What is dysplastic naevus syndrome. (2)

Answer 14

Often familial.

A large number of melanocytic naevi begin to appear in childhood even on unexposed sites.

Question 15

What is giant congenital melanocytic naevi. (2)

Answer 15

Very large moles present at birth.

Very large lesions (>20cm) show an increased risk of developing malignant melanoma.

Question 16

What is lentigo maligna. (4)

Answer 16

Slow growing macular area of pigmentation seen in elderly people, commonly on the face.
Border and pigmentation are often irregular.
Some people regard this lesion as melanoma in situ - there is an increased risk of developing invasive malignant melanoma.