One-liner#

Evaluate skin lesions to distinguish benign from malignant, identifying melanoma and non-melanoma skin cancers requiring biopsy while reassuring patients with clearly benign findings.

Quick nav#

• Red flags / send to ED
• Key history
• Focused exam
• Differential (quick pattern recognition)
• Workup
• Initial management
• Management by diagnosis
• Follow-up
• Patient instructions
• Smartphrase snippets

Red flags / send to ED#

• Rapidly growing lesion with bleeding and systemic symptoms (rare)
• Skin lesion with signs of systemic infection

Urgent (not ED, but expedited referral):

• Any lesion suspicious for melanoma → derm referral within 2 weeks
• Rapidly growing nodule → biopsy or urgent derm referral
• Non-healing ulcer >4 weeks

Key history#

Lesion characteristics:

• Duration: how long has it been there?
• Change: is it new, growing, changing color, changing shape?
• Symptoms: itching, bleeding, pain, crusting
• Prior treatment: has it been treated or biopsied before?

ABCDE for pigmented lesions:

• Asymmetry
• Border irregularity
• Color variation
• Diameter >6 mm
• Evolution (changing)

“Ugly duckling” sign:

• Lesion that looks different from patient’s other moles
• Often more concerning than ABCDE criteria

Risk factors for skin cancer:

• Fair skin, light eyes, red/blonde hair
• History of sunburns, especially blistering burns
• Chronic sun exposure (outdoor work, tanning beds)
• Personal history of skin cancer
• Family history of melanoma
• Immunosuppression (transplant, HIV, immunosuppressive medications)
• Multiple atypical nevi (>50 moles)
• Prior radiation therapy

Location:

• Sun-exposed areas (face, ears, scalp, arms, hands) → higher risk for BCC, SCC
• Trunk, legs → melanoma common sites
• Palms, soles, nail beds → acral melanoma (more common in darker skin)

Focused exam#

Systematic approach:

1. Good lighting (natural light or bright exam light)
2. Examine entire lesion
3. Compare to surrounding skin and other lesions
4. Palpate for depth, texture, tenderness
5. Check regional lymph nodes if suspicious for malignancy

Key features to document:

• Location
• Size (measure in mm)
• Shape: round, oval, irregular
• Border: well-defined vs ill-defined, regular vs irregular
• Color: uniform vs variegated, specific colors present
• Surface: smooth, rough, scaly, ulcerated, crusted
• Elevation: flat, raised, pedunculated
• Texture: soft, firm, hard

Dermoscopy (if available):

• Magnified, polarized view of lesion
• Improves diagnostic accuracy
• Specific patterns for melanoma, BCC, seborrheic keratosis

Differential (quick pattern recognition)#

Common/likely (outpatient) — Benign lesions#

Can’t-miss / urgent — Malignant or premalignant lesions#

Workup#

Most skin lesions are diagnosed clinically. Biopsy is the definitive test when diagnosis is uncertain or malignancy suspected.

When to biopsy (or refer for biopsy):

• Any lesion suspicious for melanoma
• Non-healing ulcer or erosion >4 weeks
• Rapidly growing nodule
• Lesion with uncertain diagnosis
• Pigmented lesion with ABCDE features
• “Ugly duckling” lesion

Biopsy types:

PCP role in biopsy:

• Many PCPs perform shave and punch biopsies
• If comfortable, can biopsy clearly benign-appearing lesions or suspected BCC/SCC
• Refer to derm for suspected melanoma (excisional biopsy preferred)

When NOT to biopsy:

• Clearly benign lesions (classic seborrheic keratosis, cherry angioma, skin tag)
• Patient preference for observation
• Lesions in cosmetically sensitive areas (refer to derm/plastics)

Initial management#

Benign lesions:

• Reassurance and education
• No treatment required unless symptomatic
• Removal options if desired: cryotherapy, shave removal, excision

Suspicious lesions:

• Do not treat empirically (e.g., with cryotherapy) without diagnosis
• Biopsy or refer for biopsy
• Document thoroughly with photos if possible

Premalignant lesions (actinic keratoses):

• Treat to prevent progression to SCC
• Options: cryotherapy, topical treatments, derm referral for field therapy

Management by diagnosis#

Seborrheic keratosis#

Education:

• Benign growths; extremely common in older adults
• NOT precancerous; do not become melanoma
• “Stuck on” appearance is characteristic
• Can be removed if irritated or for cosmetic reasons

Treatment:

• No treatment needed
• If symptomatic or cosmetically bothersome:
  • Cryotherapy (liquid nitrogen)
  • Shave removal
  • Electrodesiccation

When to reconsider diagnosis:

• Rapid change in size or color
• Bleeding without trauma
• Irregular borders or color variation
• If uncertain, biopsy

Follow-up: None needed unless changes occur.

Actinic keratosis#

Education:

• Precancerous lesion caused by sun damage
• ~10% risk of progression to SCC if untreated (lower per individual lesion)
• Marker of sun damage; often multiple
• Treatment prevents progression

Treatment:

Individual lesions:

Field therapy (multiple lesions or field cancerization):

Counsel patients: Field therapy causes significant redness, crusting, and discomfort—this is expected and means it’s working.

Follow-up: 4-8 weeks after treatment; then every 6-12 months for skin exam.

Basal cell carcinoma (BCC)#

Education:

• Most common skin cancer; rarely metastasizes
• Caused by UV exposure
• Slow-growing; locally destructive if untreated
• Excellent prognosis with treatment

PCP role:

• Recognize and refer to dermatology
• Can biopsy if comfortable (shave biopsy acceptable)
• Definitive treatment by derm or Mohs surgeon

Treatment options (derm-performed):

• Excision
• Mohs surgery (for high-risk locations: face, ears)
• Electrodesiccation and curettage (for low-risk, superficial BCC)
• Topical imiquimod (for superficial BCC)
• Radiation (for non-surgical candidates)

Follow-up: Derm manages; PCP should do annual skin exams; 30-50% risk of second BCC within 5 years.

Squamous cell carcinoma (SCC)#

Education:

• Second most common skin cancer
• Can metastasize (higher risk than BCC)
• Often arises from actinic keratoses
• Higher risk in immunosuppressed patients

PCP role:

• Recognize and refer to dermatology
• More urgent referral than BCC, especially if immunosuppressed
• Can biopsy if comfortable

High-risk features (require more aggressive treatment):

• Size >2 cm
• Depth >2 mm
• Location: ear, lip, temple
• Poorly differentiated histology
• Perineural invasion
• Immunosuppression
• Recurrent SCC

Treatment (derm-performed):

• Excision with margins
• Mohs surgery for high-risk
• Radiation for non-surgical candidates

Follow-up: Derm manages; more frequent follow-up than BCC due to metastatic potential.

Melanoma#

Education:

• Most dangerous skin cancer; can metastasize early
• Prognosis depends on depth (Breslow thickness)
• Early detection is critical
• Requires excisional biopsy for accurate staging

PCP role:

• Recognize suspicious lesions using ABCDE and ugly duckling sign
• Urgent referral to dermatology (within 2 weeks)
• Do NOT shave biopsy suspected melanoma (need full depth for staging)
• Do NOT treat empirically with cryotherapy

ABCDE criteria:

• Asymmetry: one half doesn’t match the other
• Border: irregular, ragged, blurred
• Color: varied (brown, black, red, white, blue)
• Diameter: >6 mm (though smaller melanomas exist)
• Evolution: changing in size, shape, color

Ugly duckling sign:

• Lesion that looks different from patient’s other moles
• May be more sensitive than ABCDE

Treatment (specialist-performed):

• Wide local excision (margins based on depth)
• Sentinel lymph node biopsy for intermediate/thick melanomas
• Adjuvant therapy for advanced disease

Follow-up: Oncology/derm manages; lifelong surveillance; high risk of second primary melanoma.

Skin tags (acrochordons)#

Education:

• Benign; very common
• Associated with obesity, diabetes, pregnancy
• No malignant potential
• Can remove if symptomatic or cosmetically bothersome

Treatment:

• No treatment needed
• If removal desired:
  • Snip excision with scissors
  • Cryotherapy
  • Electrodesiccation

Follow-up: None needed.

Cherry angioma#

Education:

• Benign vascular lesion; extremely common
• Increase with age
• No malignant potential
• No treatment needed

Treatment:

• Reassurance
• If removal desired: electrodesiccation, laser (derm)

Follow-up: None needed.

Dermatofibroma#

Education:

• Benign fibrous nodule; often on legs
• May follow minor trauma or insect bite
• “Dimple sign” is characteristic
• Stable; no malignant potential

Treatment:

• Reassurance
• Excision only if symptomatic or diagnosis uncertain

Follow-up: None needed unless changes occur.

Follow-up#

• Benign lesions: No routine follow-up; return if changes
• Actinic keratoses: 4-8 weeks post-treatment; then every 6-12 months
• After skin cancer: Per specialist; typically every 3-6 months initially, then annually
• High-risk patients (history of skin cancer, immunosuppressed, many atypical nevi): Annual full skin exam

Return precautions:

• Any lesion that is changing (growing, changing color, changing shape)
• New lesion that looks different from your other moles
• Lesion that bleeds without trauma
• Sore that doesn’t heal within 4 weeks
• Any concerning new spots

Patient instructions#

• Check your skin monthly for new or changing spots. Use a mirror for hard-to-see areas or ask a partner to help.
• Look for the ABCDEs: Asymmetry, Border irregularity, Color variation, Diameter >6mm, Evolution (change).
• Pay attention to the “ugly duckling”—a mole that looks different from your others.
• Protect your skin from the sun: wear sunscreen SPF 30+, protective clothing, and avoid peak sun hours.
• Avoid tanning beds—they significantly increase skin cancer risk.
• If you’ve had skin cancer, you’re at higher risk for another. Keep all follow-up appointments.
• Call the office if you notice any changing moles, new unusual spots, or sores that won’t heal.

Smartphrase snippets#

.LESIONBENIGN Skin lesion evaluation: [location], [size] [description]. Clinical appearance consistent with [seborrheic keratosis/cherry angioma/dermatofibroma/skin tag]. Benign; no treatment required. Discussed that this is not cancerous and does not need to be removed. Patient to return if any changes in size, color, or symptoms.

.LESIONBIOPSY Skin lesion evaluation: [location], [size] [description]. [Concerning features]. Plan: [shave/punch biopsy performed today / referral to dermatology for biopsy]. Will follow up with pathology results. Discussed possibility of skin cancer and need for definitive diagnosis.

.LESIONMELANOMASUSPECT Skin lesion concerning for melanoma: [location], [size]. Features: [ABCDE criteria / ugly duckling]. Urgent referral to dermatology for excisional biopsy. Discussed importance of complete removal for accurate staging. Patient instructed to call if appointment not scheduled within 2 weeks.

.AKTREATMENT Actinic keratoses, [number] lesions on [location]. Treated with [cryotherapy / prescribed topical fluorouracil]. Discussed that these are precancerous and treatment prevents progression to skin cancer. [For topical: Counseled on expected redness, crusting, and discomfort during treatment—this is normal and expected.] Follow-up in [timeframe]. Sun protection emphasized.