Dermoscopy of Squamous Cell Carcinoma

Question 1

Name and describe the pattern of Actinic Keratosis on the face? What skin features cause this pattern to occur?

What is the difference in appearance with AK not on the face?

Answer 1

Strawberry Pattern.

Strawberry Pattern is an erythematous pseudonetwork. There are prominent yellowish hair follicles surrounded by a white halo. May appear like a target.

NB: Broken up pseudonetwork with some light pigmentation may appear like Lentigo Maligna.

On non-facial sites, AK is present with uniform pink or tan-coloured background and prominent keratin (white or yellow scale).

Question 2

Describe 5 features of Actinic Keratosis?

Answer 2

1-erythematous pseudonetwork

2-surface scale

3-linear-wavy vessels

4-follicular openings (yellow ovoid)

5-globular structures with a white halo (white circles).

Question 3

What are the other 2 names for Squamous Cell Carcinoma in situ?

What is it’s clinical appearance?

Answer 3

Intraepidermal carcinoma and Bowen’s Disease.

Clinically presents as an irregular skin-coloured, pink or brown scaly plaque

Question 4

What are 5 Dermatoscopic characteristics of SCC in situ?

Answer 4

1- ‘Glomerular vessels’ (coiled vessels) and/or Globular vessels (small red clods)

2-Small brown globules

3-Linear greyish dots

4-Homogenous pigmentation

NB: There may be superficial erosion/crusting

Question 5

Describe some differences between non-pigmented intraepidermal carcinoma and BCC, which can be difficult to differentiate.

Answer 5

Non-pigmented intraepidermal carcinoma has more scaling and the vascular pattern is glomerular/globular rather than arborising/branched in BCC. Non-pigmented intraepidermal carcinoma’s background hue tends towards an orange shade of pink, whereas BCC tends to have more blue tone. In non-pigmented intraepidermal carcinoma (using polarisation) white shiny ‘crystalline’ structures are uncommon but may form rosettes on facial skin (keratin around follicles).

NB: Compared to psoriasis, the lesion is asymmetrical and the structure irregular.

Question 6

Describe the clinical and dermatoscopic appearance of Invasive SCCs

Answer 6

Clinical Appearance:

1-Thickened Plaque or Nodule

2-(may be) A central area of superficial scale, crust or horn (white, yellowish or brown), surrounded by paler dull-white structureless zone.

3-May/may not be ulceration &/or bleeding

Dermatoscopic Appearance:

1-Irregular groups of white perifollicular circles.

2-Blood vessels are variable, with irregular round or coiled, looped, serpentine, branched or polymorphic morphology. Greater variation in vasculature is associated with less differentiation histopathologically.