Week 1 - Derm Flashcards
1
Q
Vitiligo
A
- Partial or complete LOSS of melanocytes
- Due to autoimmune
- T-cells attack melanocytes in skin and cause destruction of melanocytes resulting in hypopigmented skin
**Autoimmune lymphocyte mediated melanocyte destruction (normal enzyme)
2
Q
Albinism
A
- No melanin production/decreased production
- Inherited defect in Tyrosinase enzyme
- Normal number of melanocytes
***Congenital abscence of enzyme and melanin is not made/decreased.
3
Q
What are three pigmented lesions due to excess melanin?
A
- Freckle
- Melasma
- Solar lentigo
4
Q
What three pigmented lesions due to increased number of melanocytes?
A
- Melanocyte hyperplasia
- lentigo simplex
- Melanocytic neoplasia
- Nevi
- Melanoma
5
Q
Freckle
A
- a.k.a Ephelis, Ephelides
- small tan red macules arising in childhood
- fade and reappear in cycle
- Histology: increased pigment in basale melanocytes
- overactive melanocytes due to sun exposure
6
Q
Melasma
A
- Mask-like facial hyperpigmentation
- usually on cheeks, forehead, temples
- bilateral cheeks of face in “butterfly” pattern
- Melanocytes have enhanced pigment transfer to keratinocytes or macrophages
- thought to be estrogen related (pregnancy, oral contraceptives, hydantoin)
- resolves after pregnancy
7
Q
Solar Lentigo
A
- Hyperpigmentation of basale epidermis due to excess melanin production
- Sun protective mechanism of melanocytes
- too much sun exposure over a lifetime
- Typical farmer (>70 years old)
8
Q
Lentigo Simplex
A
- Localized hyperplasia of melanocytes
- Small brown macules
- Not sun related
- All ages
***Histopathology: Increased melanocytes, increased pigment in stratum corneum and basale epidermis, rete ridges elongated/thinned
9
Q
What is neoplasia?
A
Genetically abnormal growth (irregular cell growth).
10
Q
What is cancer?
A
Malignant neoplasm
11
Q
Benign neoplasia
A
- Neoplasm with no capability for metastasis
- Can be destructive or symptomatic
12
Q
Malignant neoplasia
A
- Neoplasm with potential for metastasis and subsequently growth/proliferation at distant site
- Often locally destructive, but may not be
13
Q
Nevi
A
- Benign neoplasms of melanocytes
- Many Types:
- Acquired/congenital = typical mole
- Junctional (epidermal), Compound (epidermal/dermal), or Dermal
- Spitz/spitzoid
- Atypical (dysplastic)
- Dermal variants
- Blue nevus
14
Q
Spitz nevi
A
Difficult to distinguish from melanoma under microscope occasionally.
ALL HAVE TO BE EXCISED.
- don’t know how they will behave
- difficult to judge malignant potential
15
Q
Dysplastic Nevi (DPN)
A
- Atypical nevi (mild, moderate, severe atypia)
- Isolated dysplastic nevus = probably no risk or minimal risk of melanoma
- Multiple dysplastic nevi = marker of increased risk of melanoma
***Should excise moderate/severe dysplastic nevi.
16
Q
Malignant neoplasm
A
- Malignant neoplasm of melanocytes
- Most arise in skin (can arise in oral/anogenital mucosa, meninges, esophagus, eye)
- Usually asymptomatic, may itch
- Change in color or size of pre-existing lesion
- RISK FACTORS: fair skin, sun exposre, many DPN
17
Q
ABCD’s of Melanoma
A
- Asymmetry
- Border
- Color
- Diameter (>6 mm = penicl eraser)
18
Q
Melanoma in situ
A
Localized to epidermis
(does not cross basement membrane)
***Benign, but likely to become malignant at some point
19
Q
Breslow depth
A
How deep melanoma invades into the dermis.
- Probability to metastasize is best predicted by depth of invasion
- ***Best prognostic indicator***
- measured in millimeters
20
Q
Breslow depth and survival rates
A
- <1mm: 5 year survival is 95-100%
- 1-2mm: 5 year survival is 80-96%
- 2.1-4mm: 5 year survival is 60-75%
- >4mm: 5 year survival is 37-50%
21
Q
Other prognostic indicators
A
- Ulceration (usually bad, rapidly growing)
- Mitotic rate
- Sentinel lymph node biopsy
- Clark level (I-V)
- Gregression
- Inflammatory pattern
22
Q
Seborrheic keratosis
A
- Most common epithelial neoplasm
- sign of aging
- benign epithelial proliferations
- “Stuck on” brown velvety papules/plaques
- exuberant keratin formation
- variable melanin
- sharply demarcated
23
Q
Fibroepithelial polyp/Acrochordon
A
Skin Tag
- Soft flesh colored bag-like tumor with stalk
- Inconsequential
- very common
- not neoplastic
- may increase in pregnancy
- may be increased in diabetes, obesity
24
Q
Epithelial Cyst
A
- Down growth of epidermis which becomes cystic
- Filled with keratin
- Subcutaneous or dermal nodule
- Rupture easily and become inflammed
- Subtypes:
- Epidermal
- Pilar
- Dermoid
- Steatocystoma multiplex
25
Actinic keratosis
* Benign neoplasm of epidermis
* may preced sqaumous cell carcinoma
* Induced by _sunlight_, ionizing radiation, arsenicals, hydrocarbons
* Rough spots on skin
* Cytologic atypia of basale layer, hyperkeratotic
* usually scaly and erythematous papules or plaques
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How do you treat actinic keratosis?
* Liquid nitrogen
* curettage
* topical chemotherapy
27
Types of Squamous cell carcinoma
* In situ: contained above the basement membrane
* Invasive: invades basement membrane and dermis (malignant)
28
Clinical presentation of Squamous Cell Carcinoma
* Usually very scaly, red, raised
* common on sun exposed skin in older people
* Risk factors: sun, carcinogens, chronic ulcer, old burn scar
* Less than 5% will metastasize
29
Basal cell carcinoma
* Most common human malignancy
* slow growing, usually older adults
* Appearance: pearly papule with telangiectasia (small dilated blood vessels near the surface)
* arise from base of epidermis
* Risk factors: sun exposure, light pigment, xeroderma pigmentosum
30
Gorlin Syndrome
* Basal cell Nevus syndrome
* Dominant inheritance (rare)
* tumor suppressor gene is mutated
* BCC at early age with abnormalities of bone, nervous system, eyes, and reproductive organs
31
Cowden's syndrome
* Hereditary condition prone to multiple hamartomas and malignancy
* Skin: multiple **trichilemmomas** (benign proliferation of hair follicle epithelium), benign keratoses on acral skin
* Mucosal papules, cobblestoning tongue
* Internal: **breast, endometrial, and thyroid carcinoma**
* ****cerebellar lesions
* Mutation in **PTEN tumor suppressor gene**
32
Sebaceous hyperplasia
* Acquired, localized increase in sebaceous glands
* Non-neoplastic
* Glands larger than normal
* Common on the face
* yellow papule
33
Sebaceous adenoma
* Benign neoplasm
* Lobular circumscribed proliferation of sebocytes and the peripheral basaloid epithelial cells
34
Sebaceous carcinoma
* Malignant neoplasm (cancer)
* Most are periocular (inner/outer eye lid)
* A periocular sebaceous neoplasm is most likely carcinoma, not adenoma or hyperplasia
* Extraocular forms are less common, but more likely to occur in **Muir Torre syndrome**
* Metastasis common (death in 20%)
35
Muir-Torre Syndrome
* Hereditary syndrome
* Germline mutation is DNA mismatch repair proteins
* **\*\*MLH1, \*\*MSH2,** MSH6, PMS2
* repair errors in base pairing during replication, especially in 1-2 bp repeats
* Skin: sebaceous adenoma and carcinoma, keratoacanthomas
* Internal: carinomas of the colon/rectum, endometrium, ovarian
* subset of hereditary non-polypsis colorectal carcinoma syndrome (HNPCC)
36
Who do you test for Muir Torre Syndrome (MTS)?
Young/adult patients with sebaceous adenoma or carcinoma.
37
Merkel Cell Carcinoma
* very aggressive epithelial neoplasm
* highly fatal due to metastasis
* most caused by polyomavirus
38
Dermatofibroma
* a.k.a. benign fibrous histiocytoma
* very common dermal proliferation of histiocytes and fibroblasts
* extremely firm, tan/brown papules
* commonly on legs
39
Dermatofibrosarcoma Protuberans (DFSP)
* Malignant form of a spindle cell stromal neoplasm
* locally aggressive
* rarely metastasize
* Protuberant nodule with a firm plauq
* honeycomb infiltration of fat
40
Hemangioma
* Benign vascular neoplasm
* well formed vascular spaces in dermis
41
Angiosarcoma
* Malignant
* Very aggressive in skin and internally
* usually fatal
* hard to treat/cure
42
Cutaneous T-cell lymphoma
* T-cells arise in marrow and travel to skin
* Usually very slowly progressive disease
* Age: \>40 years
* Looks like psoriasis, eczema, etc. in early stage
* nodules come later
43
Mycosis Fungoides
* Most common type of Cutaneous T-cell Lymphoma
* Neoplastic CD4+ cells
* Infiltrate the epidermis and form clusters
* T-cells invade the epidermis
* Patchy, circular rashes
44
Cutaneous B-cell Lymphoma
* Less common than T-cell lymphoma
* Usually solitary of few nodules rather than patches/plaques
* Usually good prognosis
* Must exclude secondary cutaneous involvement by nodal lymphoma
45
Mastocytosis
* Mast cells originate in the marrow and travel to the skin
* Classified by cutaneous vs. systemic
* Urticaria pigmentosa: localized to skin
* Darier's sign (histamine)
* Systemic mastocytosis: organ involvement
* Pruritis, flushing, runny nose, bleeding (heparin)
46
When do you do a shave biopsy?
\*\*Superficial lesions\*\*
* BCC, AK, SCC in situ, pigmented macules
* Better cosmetics
* No sutures
* Electrocautery
47
When do you do a punch biopsy?
Neoplasms involving the dermis.
* Nodular BCC
* SCC
* Melanoma
* Most RASHES
* Requires sutures
* Various sizes 4mm-8mm
48
What biopsy should a doc perform if they do not know what type of neoplasm?
\*\*\*IF YOU DON'T KNOW,
DO A **PUNCH BIOPSY**!!!
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