Derm - SK, AK, and Skin Cancer - Exam 1 Flashcards
What is curettage?
Scraping the skin away with a curette (a ring-shaped instrument)
What is electrodessication?
High-frequency current is applied to the lesion, destroying the tissue by drying it out
What is cryotherapy?
Tissue is destroyed by freezing to -40°C or below using liquid nitrogen
What are the benefits of treatment with an excisional biopsy?
- Less expensive unless reoccurrence
- Faster
- More providers can offer treatment
What are the benefits of treating with Mohs surgery?
- Complete margin analysis
- Higher cure rates
- Sparing of normal tissue
What are the cons of treating with Mohs surgery?
- Higher cost
- Longer appointment
- Subspecialist
How is the tissue examined in Mohs Micrographic Surgery (MMS) and what benefit does this provide?
Tumor margins are assessed in office to maximize tissue conservation; lowers recurrence rates
What are the 3 primary indications for Mohs surgery?
- Recurrent tumors
- Tumors > 0.6cm on the face or > 2.0cm on the body/ extremities
- High risk anatomic locations (eyelids, nose, ears, lips, genitalia, fingers)
What is the process used in Mohs surgery?
First thin layer removed (removing visible lesion on skin) then additional layers removed until all cancer is removed
What is a solar lentigo?
A local proliferation of melanocytes caused by UV damage in sun exposed areas; very common
What are solar lentigos often referred to as?
“Age spots” or “senile freckles”
What is the clinical presentation of a solar lentigo?
- Well circumscribed
- Small brown macule, often found in groups
In what case would you treat a solar lentigo?
Cosmetic considerations only (otherwise typically no treatment required)
What is a seborrheic keratosis (SK)?
- common benign epidermal lesion caused by proliferation of immature keratinocytes
- develop typically after age 50 (“barnacles of aging”)
- genetic link to excess multiple SK’s
What is the typical clinical presentation of a seborrheic keratosis?
- Tan to black with warty, waxy, “stuck on” appearance
- Well demarcated, oval/ round/ irregular shape
- May have single SK or hundreds
What areas of the body are SK’s typically found and what pattern can they display?
Chest, back, head, neck; Christmas tree appearance of back due to Blaschko Lines
What is an ISK?
An SK that has become irritated as a result of rubbing/ friction; may have pruritus, pain, or bleeding
What is the Leser-Trélat sign?
- Sudden onset of multiple SK’s with inflammatory base; present with skin tags and acanthosis nigricans
- Possible association with GI and lung cancers
How is an SK diagnosed?
- Typically clinical diagnosis
- Biopsy may be needed if diagnosis uncertain
What should be considered with an SK?
-Reassurance; consider removing for cosmetic reasons or some ISK’s
What are the treatment options for an SK?
Cryotherapy, shave biopsy with 15 blade, curettage, electrodessication
What is the clinical presentation of a keratoacanthoma?
- Hallmark: rapid growth over 6-8 weeks
- Round, flesh colored nodule with central keratin plug
- More commonly found in sun exposed areas
What are the risk factors for a keratoacanthoma?
- Middle-age to elderly with fair skin
- Increased UV radiation or chemical carcinogens
What is the management for keratoacanthoma?
- Majority resolve spontaneously in 6-9 months
- Due to difficult diagnosis, requires biopsy/ treatment (excisional biopsy is typically preferred)
Why is treatment of a keratoacanthoma controversial?
Benign vs. pseudo-malignant appearance; many consider less aggressive squamous cell carcinoma with rare metastatic potential
What is an actinic keratosis (AK)?
A pre-cancerous lesion originating from a keratinocyte (also known as solar keratosis)
What type of skin cancer does an actinic keratosis have the potential to develop into?
Squamous cell carcinoma (SCC); 8% risk per year
What are the risk factors for AK’s?
- Increasing age
- Male
- Light skin complexion (Fitz I, II)
- Chronic UV light exposure
- History of sunburns
- Immunosuppression
- Genetic syndromes
What is the Fitzpatrick Scale used for and what are the levels?
-Classifying skin types; I (very fair)- VI (very dark)
What is the clinical presentation of an AK?
- erythematous, scaly/ gritty macule or papule (feels like sandpaper)
- may be tender
How is an AK diagnosed?
- typically clinical diagnosis based on visualization/ touch
- dermoscopy may be helpful
- shave or punch biopsy if unable to differentiate from SCC
In what cases would you consider a shave/ punch biopsy for diagnosis of an AK?
- lesion > 1cm
- rapid growth
- ulceration or pain associated
- caution if lesion is > 6mm- consider SCC in situ)
What should be considered in the management of AK’s?
May spontaneously resolve (20-30%) but could reoccur
How are AK’s treated?
- Isolated lesions: cryotherapy or surgical intervention
- Multiple lesions: fluorouracil cream (preferred), photodynamic therapy (PDT), imiquimod (Aldara)
What is the spectrum of development of an SCC?
Photodamaged skin > AK > SCC in situ (Bowen’s Disease) > invasive SCC
What are risk factors for skin cancer?
- Sun exposure, sunburns, tanning beds
- More exposure= higher risk
- Fair skin higher risk than dark skin
What is the most common type of skin cancer?
Basal cell carcinoma (BCC)
What does BCC arise from?
Basal layer of epidermis
What is the clinical presentation of BCC?
- flesh-colored or pinkish
- pearly papule/ nodule
- telangiectasia
- may have central ulceration with rolled border
- most common on head and neck
What is the most common subtype of BCC?
Nodular BCC
How else may a BCC present besides the classic pearly papule/ nodule?
Superficially as a pink patch similar to AK or SCC in situ; pigmentation may also be present
What method of treatment is preferred for BCC (Nodular)?
Surgical (vs. nonsurgical)
What surgical options exist for the treatment of BCC?
- Curettage and Desiccation
- Excision with 4mm margins
- Mohs for high-risk or cosmetic reasons
What non-surgical options exist for the treatment of BCC (Nodular)?
Radiation (for poor surgical candidates)
What are common treatment options for superficial BCC?
- Imiquimod cream
- 5% fluorouracil cream
- Photodynamic therapy
What is the prognosis for BCC?
- Locally invasive
- May recur requiring routine f/u for surveillance (6-12 mo. X 2 years then annual f/u)
- Metastasis is rare
- Higher risk for developing other NMSC (non-melanoma skin cancers)
- Appropriate education
What is the second most common type of skin cancer?
Squamous cell carcinoma (SCC)
What cells do SCC’s originate from?
Keratinocytes
What are the risk factors for SCC?
- Males (50-70 y/o)
- UV exposure (including tanning beds)
- Genetic alterations
- Chemical carcinogen exposure
What can a SCC arise from?
An area of previous skin injury (ex. burns, scars)
What is the clinical presentation of SCC?
- Papule, plaque, nodule
- Pink, red, or skin colored
- Often asymptomatic, may be pruritic or tender)
- Lesion appears scaly, exophytic, indurated, friable
- Commonly appears warty
What treatment option is preferred for SCC?
Surgical (vs. non-surgical)
What are the possible surgical options for the treatment of SCC?
Wide excision and Mohs
What are the margins based on in regards to treatment of SCC with a wide excision?
Margins based on risk
When is Mohs recommended for the treatment of SCC?
Recommended for high-risk and cosmetic considerations
What are non-surgical options for the treatment of SCC?
Radiation, curettage, desiccation, or cryotherapy
When is radiation considered as a treatment option for BCC?
- Poor surgical candidates
- Residual tumor
When is curettage & desiccation or cryotherapy considered for the treatment of SCC?
Select low-risk or SCC in situ
What are the less effective treatment options for SCC in situ?
5-fluorouracil therapy, imiquimod cream, photodynamic therapy
What is the prognosis of SCC?
Rate of metastasis is 5%; rate increases if lesion > 2cm in diameter, > 4mm deep, or recurrent
What are the guidelines for surveillance of SCC?
Every 3-6 months x 2 years –> then every 6-12 months x 3 years –> then annually for life (AAD)
What is the average age of those diagnosed with MM?
40 y/o (rare in children)
What are risk factors for MM?
- Fair skin, blue eyes, red/ blonde hair, freckling
- > 5 atypical nevi, >25 nevi
- Immunosuppression
- Personal/ family history of MM (genetic predisposition in small percentage)
- Prolong UV exposure (blistering sunburns, UVA tanning bed exposure)
What is the clinical manifestation of MM?
- Usually asymptomatic
- Most de novo with some arising from pre-existing nexus
- Pigmented papule, plaque, or nodule
- ABCDE’s
What are the ABCDE’s of MM?
A- asymmetry- shape or color B- border- irregular C- color- dark or variations D- diameter- >6mm (pencil eraser) E- evolving- changes in above
What are the subtypes of MM?
Superficial spreading, Nodular, Lentigo maligna, Acral lentiginous
What is the most common subtype of MM and where on the body is it typically found?
Superficial spreading melanoma (70%); men: backs, women: back and legs
What part of the skin does superficial spreading melanoma affect and how does it grow?
Confined to epidermis; radial spread > vertical growth
What populations does superficial spreading melanoma typically affect?
Often younger populations
How does nodular melanoma present clinically?
Nodule is inflamed and friable
Describe the growth pattern of nodular melanoma
Rapid vertical growth, minimal radial growth; aggressive
What populations typically exhibit lentigo malignas?
Elderly with chronic sun exposure
Describe the growth pattern for lentigo malignas
Slow progression radially with rapid vertical growth; typically remains more superficial compared to nodular MM
In what populations are acral lentiginous lesions most common?
- Darker skin (African/ Asian ancestry)
- Male > Female
Describe the growth pattern of acral lentiginous lesions
Spreads superficial then vertical; larger lesions due to delay in diagnosis
What areas of the body are typically affected by acral lentiginous lesions?
Palmar, plantar, or subungual surfaces
What are two atypical presentations of melanoma?
Subungual and amelanotic
What are the common characteristics of subungual melanoma?
- Great toe or thumb
- History of trauma
- Dark streak and involves proximal nail fold
What are the common characteristics of amelanotic melanoma?
- Minimal or absent pigment
- extensive differential diagnosis
What should be done prior to taking a biopsy of a melanoma?
Photograph lesion; document size and landmark (dermatologist can also triage images)
How much skin should be taken in a biopsy of a melanoma?
Entire lesion + 1-2mm
What factors should be considered when determining the prognosis of melanoma?
Breslow depth, ulceration, mitotic rate, lymph node involvement
Who is the greatest risk for lethal melanoma?
Males over 50 living alone
Describe the screening considerations for melanoma patients
Screen high risk patients in PCP and screening every 6 months x 2 years then annually
How are tumors staged for melanoma?
TNM- tumor, node, metastasis
What is the gold standard for treating melanoma?
Wide surgical excision with 2cm clear margins
What other treatments are used for patients with melanoma besides surgical excision?
Region lymph node dissection/ sentinel node biopsy
What treatments are used for advanced metastatic disease?
- Radiation
- Chemotherapy- may be used alone or in combo with other agents
- Immunotherapy/ targeted therapy- adjunct therapy
How often are melanoma patients advised to follow up?
Every 3 months
What precautions should be taken to prevent melanoma?
- Avoid getting burned and tanning
- Daily moisturizers with sunscreen (15+)
- Sunscreen SPF 30+ with planned sun exposure
- Sun protective clothing when in the sun (including hats and sunglasses)
- If possible, avoid the sun 10am-4pm or find shade
- Avoid tanning beds
- Routine skin exams
What guidelines should be followed in regards to sunscreen application/ protection?
- Apply 30 min prior to activity and reapply every 2 hours
- Keep infants out of the sun, sunscreen only > 6 months of age
How does sebaceous hyperplasia present clinically?
- Enlarged oil gland with central clearing
- Telangiectasia wraps around (versus “over lesion” for BCC)
How does a fibrous papule present clinically?
- Benign angiofibroma
- Skin-colored/ pinkish papule on the nose
- No telangiectasia and lacks pearly texture
