Dermatopathology Flashcards
Hyperkeratosis
Thickening of the stratum corneum
Parakeratosis
Flattened, keratinocyte nuclei within the stratum corneum, where nuclei are not normally present
Orthokeratosis
Hyperkeratosis of anuclear keratinocytes within the stratum corneum
Acanthosis
Thickened stratum spinosum
Acantholysis
Loss of cohesion between keratinocytes due to dissolution of intercellular connections
Dyskeratosis
Abnormally or prematurely cornified (keratinized) keratinocytes in the epidermis that stain pink on H&E
What are the layers of the epidermis?
“Cancel labs get some beer”
Stratum Corneum Stratum Lucidum (thick skin only - palms and soles of feet) Stratum Granulosum Stratum Spinosum Stratum Basale
Papillomatosis
Irregular undulation of the epidermal surface
Solar Elastosis
Accumulation of basophilic (grey/blue) matierial in the upper dermis due to sun damage
Papule
Elevated skin lesion
Macule
Flat skin discoloration
Ichthyosis Vulgaris
A disorder of dry, scaly skin due to defective desquamation that leads to build-up into a compacted scale. Often described as “fish scales.”
What is the inheritance pattern of ichthyosis vulgaris?
Autosomal dominant mutation
Presents with severe, thick plates of scale that almost resemble reptile scales and present at birth. Mostly affects palms, soles, and flexures.
Lamellar Ichthyosis
What is the inheritance pattern of lamellar ichthyosis?
Autosomal recessive mutation
X-linked Ichthyosis
Presents as more brownish and scaly eruption in males, usually in early childhood.
What is the mutation in X-lined ichthyosis?
Mutation in STS gene leads to defective steroid sulfatase
Seborrheic Keratosis
Papillomatosis, acanthosis, and horn cyst formation. Present as stuck on plaques or verrucous lesions
Leser-Trelat Sign
Sudden onset of multiple seborrheic keratosis that is indicative of paraneoplastic syndrome and metastatic cancer
Acanthosis Nigricans
Lacks acanthosis and horn cyst. Clinically presents as a velvety plaque most common on the back of the neck or axilla.
What are fibroepithelial polyps AKA?
- Skin Tag
- Acrochordon
Common scaly erythematous patch located on sun-damaged skin - Increasingly common with age
Actinic Keratosis
What is actinic keratosis a precursor for?
SCC
What is the “flag sign?”
It is seen in actinic keratosis - Basal layer atypia with overlying parakeratosis alternating with orthoparakeratosis.
What is the most common mutation associated with SCC?
P53 mutations
Squamous Cell Carcinoma
Squamous cell carcinomas are generally erythematous, scaly papules or plaques with ill-defined borders, and they may be confused with large, hypertrophic AKs.
Clinical Presentation of SCC
SCCs usually present as firm, skin-colored to pink, papules or plaques, commonly found on the head and neck region of elderly individuals.
What is seen on histology of SCC?
- Keratin pearls
- Mitotic figures
- Cells have a glassy eosinophilic cytoplasm, with large nuclei
Bowen’s Disesase (SCC in-situ)
Full thickness atypia, basal layer sparing and may show skip areas but involves follicles with no invasion into the dermis in contrast to SCC
Bowenoid Papulosis
Similar appearance to Bowen’s disease:
- HPV-induced, located on the genitals
- Frequently multiple papules
- May spontaneous regress or progress
What is the appearance of basal cell carcinoma on the skin?
Pearly, pink papule with overlying telangiectasia
What is the most common invasive skin cancer?
Basal Cell Carcinoma
What demographic is more often affected by BCC?
Older population
What are the 2 mutations most often seen in BCC?
- p53
- PTCH
What is the most frequent location of BCC?
Sun-exposed areas
Initially presents as a small, translucent, pearly papule with telangiectasias on its surface. As the lesion progresses, the center may become ulcerated and the borders become indurated, rolled and pearly.
Nodular BCC
Where are nodular BCCs most often found?
This variant is frequently found on the face.
It appears as a pink, scaly plaque with a slight elevation pearly border. Crusting and ulceration may sometimes be present.
Superficial BCC
Where are superficial BCCs most often found?
The superficial BCC is commonly located on the thorax and limbs.
Nevoid Basal Cell Carcinoma Syndrome (Gorlin Syndrome)
Autosomal dominant disease - multiple BCCs seen before age 20 and seen with PCTH mutation
An 65 year old, Caucasian male patient present to dermatology clinic for an annual skin check. He has an occupational history as a banking executive. He splits his time between your suburban city (were they reportedly have high chlorine levels in the water system) and his near by lake home. He was very active until a chronic lower leg ulcer secondary to his severe diabetes has been affecting him the last couple of years and he reports a recent 20 pound weight gain since. His risk factors for squamous cell carcinoma include:
A) Occupational exposure, age, gender, and chronic leg ulcer.
B) Age, gender, exposure to UVB rays, chronic cutaneous wound
C) Choline exposure, diabetes, activity levels
D) Age,gender,diabetes,activitylevel,andobesity.
B) Age, gender, exposure to UVB rays, chronic cutaneous wound
Recently your Aunt has been diagnosed with cutaneous SCC. She comes to you (the family doctor) to ask what is the likely cause and outcome of her diagnosis? Which of the following is the best statement about SCC of the skin?
A) It is hereditary and it often metastases. She will require sentinel node biopsy and if positive chemotherapy.
B) Many things cause SCC but her chances are great with local radiation at the site
C) SCC is directly associated with sun exposure. The treatment is local excision. Less than 5% metastasize.
D) SCCismostcommonlycausebyoccupational exposure to carcinogen. She needs to consider suing her previous employers. She will need an excision to prevent metastasis.
C) SCC is directly associated with sun exposure. The treatment is local excision. Less than 5% metastasize.
A 13 year old patient present with 2 separate nodules that you biopsy and the path report demonstrates a proliferation of basaloid cells extending from the lowest level of the epidermis into the dermis. This patient’s tumor likely has which of the following genetic mutations:
A. A sporadic mutations in TP53
B. Familial mutation in either PATCH or TP53 genes
C. Familial mutation in CDKN2A
D. None of the above; these tumor have no known genetic mutations.
B. Familial mutation in either PATCH or TP53 genes
Freckle (Ephelis)
Small, tan-red to light brown macules on sun-exposed areas. Most common lesion of childhood.
Lentigo
Small, oval tan-brown. Mucous membranes and any age.
Melanocytic hyperplasia along the basal layer.
Melanocytic Nevi
Tan to brown macules and papules.
What are the common types of melanocytic nevi and where they are generally found?
Junctional - epidermis at the DEJ
Compound - between the epidermis and dermis with some nest present in the dermis
Intradermal - nests are exclusively within the dermis