Dr Sarma’s guide to mastering seborrheic keratosis,

verruca vulgaris, actinic keratosis and squamous cell

carcinoma

LOOK AT THE TOP AND LOOK AT THE BASE,

GET A QUICK ANSWER AND CLOSE THE CASE.

Deba P Sarma, MD

Omaha

Seborrheic keratosis

Verruca vulgaris

Actinic keratosis

Squamous cell carcinoma

Seborrheic keratosis is a benign epidermal tumor arising from the normal

basal cells. Look at the basal layer: Normal cuboidal cells

Look at the keratin on top: Normal flaky keratin

A dark, basaloid stuck-on epidermal tumor, usually above the epidermal

level composed of uniform small epidermal cells similar to the

normal basal cuboidal cells, surface keratin is normal basket-weave

type. Horn cysts are commonly seen.

Verruca vulgaris is a benign epidermal tumor induced by

virus. Look at the basal layer: Normal cuboidal cells (virus affects the suprabasal cells).

Look at the keratin on the top: Compact keratin (wart is tough!)

Well defined mature keratinocytic lesion, compact hyperkeratosis, verruciform

epidermal hyperplasia,peripheral rete ridges pointing to the center, normal cuboidal

basal keratinocytes at the base of the lesion.

Actinic keratosis is a sun-induced dysplastic epidermal lesion.

Dysplasia starts at the basal layer.

Look at the dysplastic basal cells.

Dysplastic squamous cells making abnormal non-flaky keratin on top.

Dermis shows solar degeneration.

Squamous cell carcinoma is a malignant tumor of epidermis arising

from the basal cells…… basal cells are dysplastic……

and keratin is abnormal (non-flaky).

Fronds of neoplastic squamous cells are growing downwards into the

dermis.

About IRRITATED Seborrheic keratosis ! It is irritated but neither dysplastic

nor malgnant.

Look at the basal cells: Normal cuboidal cells!

Look at the top: Compact red keratin.

No epidermal dysplasia.

Eddies ( benign small intraepidermal epithelial nests).

Eddies

LOOK AT THE TOP AND LOOK AT THE BASE,

GET A QUICK ANSWER AND CLOSE THE CASE.

D Sarma, MD

Omaha

SUMMARY