Tumors of the Dermis

Question 1

dermatofibroma

Answer 1

• fibroblasts with collagen
• aka benigni hisitocytoma
• very common in lower legs
• diplays the dimple sign
• can be pruritic
• kina looks like a dysplastic nevus
• whirly collagen

Question 2

dermatofibrosarcoma

Answer 2

• locally aggressive but rarely metastasizes
• extends into the subQ fat in a honeycomb pattern
• fibroblasts in pinwheel pattern

Question 3

mycosis fungoides

Answer 3

• usually on the trunk
• patch, plaque, nodule (same as kaposi’s sarcoma)
• cd4 cells (sezary) form bands in superficial dermis
• invade epidermis

Question 4

mastocytosis

Answer 4

• urticaria pigmentosa (children)

- systemic mastocytosis (adults) bone marrow

Question 5

mastocytosis

Answer 5

• darier sign: wheal when skin is rubbed
• dermatographism
• systemic

Question 6

mastocytosis histology

Answer 6

granules

• monomorphous
• no epidermis
• fried egg cells
• giemsa stain helps visualize mast cell granules