Epidermal tumors Flashcards
(54 cards)
What is seborrheic keratosis?
Single or multiple sharply demarcated pigmented lesions that protrude above the skin surface
What is the appearance of seborrheic keratosis?
Soft tan-black greasy surface lesions
Where can seborrheic keratosis occur?
Anywhere except palms and soles
What is the Leser-Trélat sign?
Sudden appearance and increase in number and size of seborrheic keratoses associated with internal malignancy
What malignancy is Leser-Trélat sign typically associated with?
Gastrointestinal malignancy
What is the histological feature of seborrheic keratosis?
Proliferation of squamous epithelium with keratin-filled cysts
What mutation is associated with seborrheic keratosis?
Activating mutations in FGFR3
What causes actinic keratosis?
Excessive chronic exposure to sunlight leading to TP53 mutation
How is actinic keratosis classified?
Premalignant proliferation
What is the appearance of actinic keratosis?
Hyperkeratotic scaly plaques on face
What texture does actinic keratosis have?
Red and rough sandpaper-like texture
Who is most commonly affected by actinic keratosis?
Old patients
What are the microscopic features of actinic keratosis?
Basal cell and squamous layer atypia
What can actinic keratosis evolve into?
In situ or invasive squamous cell carcinoma (Bowen’s disease)
Are malignant tumors of the skin common?
Yes
Where do most malignant skin tumors present?
On sun-exposed skin.
What is the most common malignant tumor in the skin?
Basal cell carcinoma (BCC).
What causes basal cell carcinoma?
Sun exposure in patients over 40 years old with fair skin.
Where does basal cell carcinoma mainly occur?
On the face and sun-exposed skin
Does basal cell carcinoma metastasize?
No
What are the genetic defects associated with basal cell carcinoma?
DNA repair defects and TP53 mutations.
What gene mutation is specifically linked to basal cell carcinoma?
PTCH gene mutation affecting the Hedgehog pathway.
What is Gorlin Syndrome?
A condition with multiple basal cell carcinomas at early age
What is the treatment of choice for basal cell carcinoma?
Surgical excision.
