DERMA Flashcards
Cocks peculiar tumor
Infected and ulcerated sebaceous cyst
Some features of sebaceous cysts
Have central punctum
Mostly contain sebum
Most common scalp, ears, back, face, and upper arm (not palms of the hands and soles of the feet).
What can cause reoccurence of sebaceous cyst
Excision of the cyst wall needs to be complete to prevent recurrence
Most common cause of acanthosis nigricans
Insulin resistance
Long standing nonhealing ulcer on medial malleolus
What to do
Perform punch biopsy
If suspected melanoma/pigmented lesions
What not to do
Don’t perform incisional biopsy
Perform excisional biopsy
SCC Of skin is associated with which premalignant conditions
Pre-malignancy conditions, such as Bowen’s disease or actinic keratoses
Squamous cell carcinoma in situ
Also known as
Bowen disease
How to differentiate between melanoma vs SCC
immunohistochemistry with S100
Basosquamous carcinoma feature
Basaloid histological BCC features with eosinophillic squamoid features of SCC
Risk factor for Basal cell carcinoma
Xeroderma Pigmentosa or Gorlin syndrome).
psoriasis, Fitzpatrick type 1 skin, immunosuppression
Dome shaped erythematous lesions that develop over a period of days and grow rapidly. They often contain a central pit of keratin.
Keratoacanthoma
Rx of Keratoacanthoma and pyogenic granuloma
curettage and cautery
Sun exposure pattern in SCC vs BCC
For SCC’s the major pattern is in chronic long term exposure. For BCC’s, the pattern of sporadic exposure with episodes of burning is more important.
Whixh viral DNA is found in the majority of transplant recipient SCC’s
Human papilloma virus
Sebum in cyst with outer root sheath of hair follicle
Pilar cyst
raised pearly edges in an ulcerated lesion at a sun exposed site
BCC
Diagnostic point for PYOGENIC GRANULOMA
Trauma is a common precipitant of pyogenic granuloma and contact bleeding and ulceration are common
treatment for an infected sebaceous cyst is
incision and drainage with removal of the cyst wall.
Dermoid cyst features
Have hair
Midline
Dumbell shaped
Skin lesion associated with Crohns vs celiac
Crohn : pyoderma gangrenosum
Celiac: dermatits herpatiformis
Which lesion feel larger than it appears
Dermatofibroms
Dermatofibroma features
may be pigmented
are often larger than they appear.
They frequently occur at sites of previous trauma.
What mutation in atypical naevi
CDKN2A gene
Spitz naevus is common in which age group
Children
Junctional melanocytic naevi features
Circular macules
May have heterogeneous colour even within same lesion
palms, soles and mucous membranes are
Which lesion is heterogenous in appearance
Junctional melanocytic naevi
scaly, thick, greasy surface with scattered keratin plugs
Dx
Seborrheic keratosis
skin lesions most likely to resemble a malignant melanoma?
Spitz naevi
Thus remove them
seborrhoeic warts features
Itchy pigmented lesions mostly over trunk
seborrhoeic warts Rx
lesions are often extensive and superficial. Shave excision will suffice, material must be sent for histology
