Benign and premalignant skin lesions

Question 1

Explain seborrhoeic keratoses

Answer 1

• Benign, but commonly referred
• Warty growths, “stuck on appearance”
• Can have variable appearance
• Patients often have multiple +/- cherry angiomas
• Generally left untreated, but if troublesome
  * Cryotherapy
  * Curettage

Question 2

What is cryotherapy? (including pros and cons)

Answer 2

• Liquid nitrogen
• Pros
  * Cheap
  * Easy to perform “on the day”
• Cons
  * Can scar
  * Failure/Recurrence
  * No pathology result

Question 3

What is the sign of Leser-Trelat?

Answer 3

• Paraneoplastic phenomenon
• Abrupt onset of widespread seborrhoeic keratosis, particularly in a younger individual
• SKs remain benign but may indicate underlying solid organ malignancy
  * GI adenocarcinoma

Question 4

Explain viral warts

Answer 4

• Due to Human Papilloma Virus
• Rough hyperkeratotic surface
• Difficult to treat
  * Do we need to treat at all?
• Will clear when immunity developed to virus
• Cryotherapy or wart paints can stimulate immune system slightly
• Can curette in severe cases

Question 5

Explain cysts

Answer 5

• Encapsulated lesion containing fluid or semi-fluid material
• Usually firm and fluctuant
• Common. Affect ~20% adults

Question 6

What are the different types of cysts?

Answer 6

• Epidermoid cyst (often wrongly called sebaceous)
• Pilar cyst
• Steatocystoma
• Dermoid cyst
• Hidrocystoma
• Ganglion cyst

Question 7

What are the complications of cysts?

Answer 7

• Can rupture and cause inflammation of surround skin

- May become secondary infected

Question 8

What is the treatment of cysts?

Answer 8

• Treated with excision
• If inflamed/infected
  * Antibiotics
  * Intralesional steroid
  * Incision & Drainage

Question 9

What is a dermatofibroma?

Answer 9

• Benign fibrous nodule, often on limbs
• Proliferation of fibroblasts
• Cause is unknown. They are sometimes attributed to an area of trauma.
• Firm nodule, tethered to skin but mobile over fat. Pale pink/brown. Often paler in centre.
• Dimple sign positive
• Usually asymptomatic. Can be itchy or tender
• Excision if concern or symptomatic.

Question 10

Explain lipomas

Answer 10

• Benign tumour consisting of fat cells
• Common
• Cause unknown
• Smooth and rubbery subcutaneous mass
• Usually asymptomatic
• If tender
  * ?angiolipoma
  * ?Liposarcoma – rare malignancy

Question 11

Explain angioma

Answer 11

• Overgrowth of blood vessels in the skin due to proliferating endothelial cells
• Generally asymptomatic. Can be unsightly or bleed
• Occur in all age groups, both sexes
• Pregnancy & liver disease
• Excision or laser

Question 12

Explain pyrogenic granuloma

Answer 12

• Rapidly enlarging red/raw growth, often at a site of trauma.
• Bleed easily
• Cause is unknown
• Occur in up to 5% of pregnancies
• Common on head and hands
• Removed by curettage & cautery

Question 13

Explain actinic keratoses

Answer 13

• Common
  * Around 20% of 60yr + had at least one AK in UK study
• May spontaneously resolve
• Low risk of malignant progression to SCC
  * If average of 7.7 AK, the probability of developing an SCC within 10 years is 10%
• A chronic medical condition

Question 14

What is Bowen’s disease?

Answer 14

• aka Intraepidermal squamous cell carcinoma
  * Full thickness dysplasia, entirely contained within the epidermis, no metastatic potential
  * Potential to become malignant (around 5%)
• Irregular, scaly erythematous plaque

Question 15

What is the treatment of Bowen’s disease?

Answer 15

• Cryotherapy
• Curettage
  * Lesion scraped off and heat applied to seal vessels and destroy residual cancer cells
• Photodynamic therapy
• Imiquimod

Question 16

What is photodynamic therapy?

Answer 16

• Photochemical reaction to selectively destroy cancer cells
• Topical photosensitising agent applied
• Concentrates in cancerous cells
• Red light applied ( light colour dependant on which agent is used)
• Photodynamic reaction occurs between light, photosensitizers and oxygen causing inflammation and destruction of cells

Question 17

What are the pros and cons of photodynamic therapy?

Answer 17

Pros

• Done for the patient by hospital staff
• Can treat multiple areas, including those which would be hard to reach by patient
• 1 or 2 treatments

Cons

• Requires hospital appointments
• Can be painful and scar

Question 18

Explain Imiquimod

Answer 18

• Aldara
• Immune response modifier
  * Stimulates cytokine release: inflammation and destruction of lesion

Pros

• Useful where surgery is undesirable
• Usually good cosmetic result
• Large surface area

Cons

• Treatment time is 6 weeks
• Significant inflammation
• Failure/recurrence

Question 19

What is the treatment of actinic keratoses?

Answer 19

• Cryotherapy
• Curettage
• Diclofenac Gel
• Imiquimod

Question 20

What is melanoma in situ?

Answer 20

• Melanoma cells entirely confined to epidermis
• No metastatic potential
• Treated with excision

Question 21

What is lentigo maligna?

Answer 21

• Type of melanoma in situ

- Usually facial