Derm E2: skin cancer

what is the most common form of skin cancer?

basal cell carcinoma

What are clinical features of basal cell carcinoma (BCC)?

rare to metastasize- grows slowly

nodular: firm, translucent or pearly skin colored smooth nodule w/ telangectasias; well defined, rolled border

superficial: thin scaly plaques, pink/red w/ fine threadlike border and telangiectasias; periphery may be rimmed w/ fine translucent papules

morpheaform: smooth, flesh colored papules, may be atrophic, lesions can bleed w/ minimal trauma, majority on head or neck

what are risk factors for BCC?

genetics, sun exposure, Fitzpatrick I-II, hx radiation or phototherapy exposure

How do you dx BCC?

skin bx; histopathology shows islands of basaloid cells

what is 1st line tx for BCC?

excision→ preferred is Mohs surgery (nasolabial area, around eyes, ear canal, posterior auricular sulcus, scalp)

electrodessication and curettage

What is 2nd line tx for BCC?

topical imiquimod or 5-FU

What is squamous cell carcinoma (SCC)?

malignant cutaneous tumor arising from epidermal keratinocytes

caused by DNA mutations from UV exposure, smoking, aging, and immune suppression

what are risk factors for SCC?

sun exposure, immunosuppression

what are clinical features of SCC?

• may present in multiple ways- papules, scaly or crusted plaques, nodules, hyperkeratotic

• grows over wks-mos

• may ulcerate

• lesions may be tender/painful

• can present as in situ vs invasive

what are clinical features of SCC in situ / Bowen’s dz?

• slow growing, erythematous, well demarcated scaly patch/plaque

• typically asx- pain/tenderness suggest invasive

• Erythroplasia of Queyrat- red plaque on on glans penis or labia minora; may be assoc. w/ bleeding, pruritus, pain

What is the histopathology of SCCIS?

keratinocytes dysplasia of full thickness of epidermis w/o infiltration of atypical cells to dermis; thickening of epidermis (acanthosis); hyperkeratosis and parakeratosis of stratum corneum

what are clinical features of invasive cutaneous SCC?

• well differentiated lesions → indurated, firm, hyperkeratotic papules, plaques, nodules

• poorly differentiated → fleshy, granulomatous papules, nodules; w/ ulceration, hemorrhage, necrosis

• slowly evolving → tissue destruction; can metastasize 1-3 yrs after initial dx; can cause burning/paresthesias/visual changes if neural invasion

what is histopathology of invasive cutaneous SCC?

dysplastic keratinocytes involving full thickness of epidermis that penetrates epidermal basement membrane to involve dermis or deeper tissue

what are high risk features of recurrence/metasstasis of invasive SCC?

• located on lips, ears, forehead, cheeks

• > 2cm

• recurrent or multiple tumors

• wounds, scars, or sites of previous radiation

• neuro sx

• clark level IV or higher (invades reticular dermis or SC fat)

Where is SCC located?

sun exposed: face, ears, hands, forearms, legs

atypical: anogenital region or areas w/ chronic inflammation

how do you dx SCC?

skin bx- confirm dx, stage, and aid w/ management

histology: keratinocytic dysplasia

dermoscopy: differentiate b/t in situ vs invasive

what is 1st line tx for SCC?

surgical excision

alt: Mohs surgery

what is 2nd line tx for SCC?

nonsurgical options- electrodessication and curettage, cryotherapy (only for low risk, well defined lesions)

what is Merkel cell carcinoma?

rare, aggressive cutaneous malignancy that typically appears in older individuals

what are clinical features of Merkel cell carcinoma?

• rapidly growing, firm, contender intracutaneous nodule

• skin colored or bluish-red

• 1cm - 2cm+

• high risk of metastasis

• located in sun exposed areas

How do you dx Merkel cell carcinoma?

skin bx; AEIOU mnemonic:

Asx or non tender

Expanding rapidly

Immune suppressed

Older than 50

UV exposed skin

What is the management for Merkel cell?

requires imaging for metastasis, staging, and sentinel node bx

What is melanoma?

potentially deadly form of skin cancer → uncontrolled growth of melanocytes occurring in 2 growth phases

radial/horizontal- arises from superficial tumor confined to epidermis

vertical- invade basement membrane and deeper tissues

Where can melanoma be located?

anywhere on body including oral cavity, genitalia, glans or prepuce, labia minora, mucus membranes (lining of resp, GI, GU, rare)

what are risk factors for melanoma?

MMRISK

Moles: atypical/dysplastic nevus >5

Moles: common moles > 50

Red or blonde hair and freckling: these ppl often have few or no moles

Inability to tan: Fitzpatrick I and II

SunburnL severe sunburn < 14 y/o

Kindred: FHx melanoma

What would dermoscopy show for melanoma?

atypical pigment: brown-black dots/globules; 5-6 colors asymmetrically distributed; blue-white-veil depigmentation; irregular vascular pattern

what is dx workup for melanoma?

history

PE- ABCDE

dermoscopy- atypical pigment

Skin bx/pathology: excisional bx should include 2mm margins; breslow thickness (strongest predictor of outcome) and clark levels

staging- if regional LN involved

what is tx for melanoma?

surgical excision- only curative if early

for stage III-IV distant metastases- surgery ± chemo, radiation, palliative care

How often should follow ups be for melanoma?

skin check every 3-6 mos for 3 years

PE and labs yearly

ophthalmology exam yearly

(late recurrence can occur >10 yrs after dx)

what are clinical features of superficial spreading melanoma?

• MC histological subtype of melanoma

• variably pigmented macule or thin plaque w/ irregular border ranging few-several cm

• multiple shades of red, blue. black, gray, white

• traditionally stays in horizontal growth phase

• dermoscopy inc dx accuracy >50%

• located anywhere on body

• histology- asymmetric, poorly circumscribed, lack cellular maturation

what are clinical features of nodular melanoma?

• enters vertical growth phase from inception

• darkly pigmented, pedunculate or polypoid papules/nodules

• uniform color or melanotic, symmetric orders, small diameter → early detection difficult

• >2mm thick upon dx

• rapidly enlarges over wks to mos

• may ulcerate or bleed

what are clinical features of lentigo malignant melanoma?

• commonly arises on sun damaged areas of skin in older pts

• begins as freckle like, tan or brown macule

• gradually enlarges and darkens w/ asymmetric foci or pigmentation, color variegation

• raised areas signify vertical growth into dermis

• blurred borders w/ notch “geographic” shapes

what are clinical features of acral lentiginous melanoma?

• MC type of melanoma seen in Fitzpatrick III and above

• arises most commonly on palmar, plantar, subungual, and mucosal surfaces

• dark brown/black, irregularly pigmented macules or patches w/ raised areas, ulceration, bleeding

• occasionally can present as amelanotic/hypomelanotic lesions

• slow growing- can take mos-yrs

• hutchinson’s sign- involvement of proximal nail fold

what are clinical features of amelanotic melanoma?

• melanoma lesion w/ NO pigment

• may present as pink or red ,accuses/papules/nodules

• well defined borders

• often clinically confused w/ benign lesions (hemangioma, pyogenic granuloma, SKs)

what is mycosis fungoides?

cutaneous T cell lymphoma, form of non-hodgkin lymphoma that presents as patches, plaques, tumors, or erythroderma

unknown cause

what are clinical features of mycosis fungoides?

• presents as chronic itch (even before clinical signs)

• patch stage: poorly defined, irregular scaling red patches

  • hypopigmented variant- pale, finely scaly patches

• plaques stage: well demarcated, annular itchy thickened lesions w/ red, violet, or brown color

• tumor stage: large irregular lumps (>1cm) developing from plaques

How do you dx mycosis fungoides?

skin bx

what is tx for mycosis fungoides?

UVA phototherapy, TCS, topical chemotherapy, radiation