Skin Biopsy Techniques

1. Procedure Overview

Summary

Skin biopsy is a fundamental diagnostic procedure in dermatology, primary care, and plastic surgery, used to obtain tissue for histopathological and immunological analysis. [1,2] The four principal techniques are punch biopsy, shave biopsy, incisional biopsy, and excisional biopsy. Selection of the appropriate technique depends upon the suspected pathology, lesion depth, anatomical location, and cosmetic considerations. [3]

Correct technique selection is paramount: a shave biopsy on a suspected melanoma constitutes a serious clinical error as it prevents accurate Breslow depth measurement, which is essential for staging and determining surgical margins. [4,5] This comprehensive guide covers indications, technique selection, procedural steps, specimen handling, post-procedure care, and common pitfalls relevant to postgraduate examinations.

Key Facts

Critical Safety Points

The Melanoma Rule: If there is ANY doubt about a pigmented lesion, excise completely with 2mm clinical margin. A shave biopsy that transects a melanoma destroys Breslow depth information essential for staging and prognosis. [4,5,6]

The SCC Rule: For suspected squamous cell carcinoma on sun-damaged skin, a deep shave (saucerization) or punch biopsy is acceptable for diagnosis, but definitive excision with appropriate margins must follow if malignancy is confirmed. [7]

The Adrenaline Myth: The historical teaching to avoid adrenaline-containing local anaesthetics in fingers, toes, ears, nose, and penis has been definitively disproven. Multiple large studies demonstrate safety with no cases of digital necrosis. [8,9,10]

The DIF Rule: For suspected autoimmune bullous disease, Direct Immunofluorescence requires perilesional skin in Michel's transport medium, NOT formalin. Formalin destroys immunoglobulins. [11,12]

Why This Matters Clinically

Skin biopsy is one of the most commonly performed procedures in medicine, with over 10 million performed annually in the United States alone. [13] A poorly chosen technique can delay diagnosis, cause cosmetic disfigurement, or destroy critical staging information for skin cancer. Every clinician performing minor surgery must master these skills and understand the clinical reasoning behind technique selection.

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2. Anatomy Essentials

Skin Structure and Biopsy Depth

Understanding skin architecture is fundamental to technique selection:

Relaxed Skin Tension Lines (RSTLs / Langer's Lines)

The key to optimal scarring in excisional biopsies:

• RSTLs run parallel to underlying muscle fibres and correspond to natural skin creases
• On the face, they follow crow's feet, nasolabial folds, and forehead creases
• Ellipse orientation: Always align the long axis of your ellipse ALONG the RSTLs
• Result: Scars fall into natural creases and become significantly less visible [14]

Danger Zones (Anatomical Hazards)

Blood Supply Considerations

Regional blood supply affects healing and complication rates:

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3. Local Anaesthesia

Pharmacology

Maximum Volume Calculations

For lidocaine 1% with adrenaline (10 mg/mL):

• 70 kg adult: Maximum 7 mg/kg = 490 mg = 49 mL of 1% lidocaine with adrenaline
• 50 kg patient: Maximum 350 mg = 35 mL of 1% lidocaine with adrenaline

Practical tip: For minor skin biopsies, volumes of 1-5 mL are typical, well below toxic thresholds.

Adrenaline Safety Evidence

The traditional teaching to avoid adrenaline in digits has been definitively disproven:

Current evidence-based practice: Adrenaline 1:100,000 or 1:200,000 is safe in all anatomical locations including digits, ears, nose, and penis when used appropriately.

Benefits of Adrenaline in Local Anaesthesia

1. Vasoconstriction: Provides bloodless operative field
2. Delayed absorption: Prolongs anaesthetic duration
3. Reduced systemic toxicity: Lower peak plasma levels
4. Reduced total anaesthetic requirement: Better tissue penetration

Injection Technique

Pain reduction strategies (evidence-based):

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4. Indications for Biopsy Technique Selection

Technique Selection Algorithm

Quality Markers for Skin Biopsy

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5. Technique: Shave Biopsy

Definition and Mechanism

Shave biopsy removes a superficial portion of skin tangentially, including epidermis and variable amounts of dermis. The depth is controlled by blade angle and technique. [2,3]

Indications

Equipment Required

• Antiseptic (chlorhexidine 0.5% in alcohol or povidone-iodine)
• Lidocaine 1-2% with adrenaline 1:100,000
• 2mL syringe, 25G (orange) needle
• No. 15 scalpel blade OR DermaBlade
• Toothed forceps (Adson or Gillies)
• Haemostatic agent (aluminium chloride 20% / ferric subsulfate)
• Specimen pot with 10% buffered formalin
• Non-adherent dressing

Procedure: Step-by-Step

Step 1: Preparation and Consent

• Explain procedure, expected outcome, scar appearance
• Document consent including: bleeding, infection, incomplete excision, scar

Step 2: Anaesthesia

• Clean site with antiseptic
• Inject local anaesthetic beneath lesion, creating a raised bleb
• Adrenaline-containing LA elevates lesion and provides haemostasis
• Wait 2-5 minutes for full effect

Step 3: Technique

• Hold blade parallel to skin surface (for superficial shave)
• Angle blade 10-15° below horizontal for deeper sampling (saucerization)
• Use gentle sawing motion to slice through base of lesion
• Support lesion with forceps if needed (avoid crushing diagnostic tissue)
• For saucerization: scoop downward to include mid-dermis

Step 4: Haemostasis

• Apply aluminium chloride 20% (Monsel's solution) with cotton-tipped applicator
• Alternative: light electrocautery or silver nitrate
• Pressure for persistent oozing

Step 5: Specimen Handling

• Place specimen in formalin immediately
• Ensure adequate formalin volume (10:1 ratio formalin:tissue)
• Label container clearly

Step 6: Dressing

• Apply non-adherent dressing (Mepitel, Adaptic, or Allevyn)
• Wound heals by secondary intention over 1-3 weeks

Saucerization (Deep Shave) Technique

For deeper sampling without ellipse:

• Angle blade 30-45° and scoop to create dish-shaped excision
• Allows sampling of mid-dermis
• Useful for: suspected BCC, thick seborrhoeic keratoses, superficial SCC
• Never for melanoma - still cannot assess true depth

Complications

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6. Technique: Punch Biopsy

Definition and Mechanism

Punch biopsy uses a circular cutting instrument to obtain a full-thickness cylindrical core of tissue including epidermis, dermis, and variable subcutaneous tissue. This is the gold standard for inflammatory dermatoses. [1,2,15]

Indications

Punch Size Selection

Equipment Required

• Antiseptic solution
• Lidocaine 1-2% ± adrenaline
• Disposable sterile punch (appropriate size)
• Toothed forceps (fine-tipped)
• Iris scissors (curved)
• Suture material (non-absorbable 4-0 to 6-0 nylon or absorbable)
• Specimen pot with 10% buffered formalin (or Michel's medium for DIF)
• Needle holder
• Dressing materials

Procedure: Step-by-Step

Step 1: Site Selection

• Choose representative area of pathology
• For inflammatory disease: include junction of normal and abnormal skin
• For bullous disease: perilesional skin for DIF (uninvolved skin adjacent to blister)
• Avoid areas of secondary change (excoriation, lichenification)

Step 2: Consent and Preparation

• Explain procedure and expected scar (small circular/elliptical)
• Document consent for bleeding, infection, scarring, need for repeat biopsy

Step 3: Anaesthesia

• Clean with antiseptic
• Inject LA beneath lesion to raise bleb
• Avoid injecting into the lesion itself (distorts histology)
• Wait for full anaesthetic effect

Step 4: Skin Stretching Technique (Critical)

• Stretch skin perpendicular to RSTLs using non-dominant hand
• This converts the circular defect into an elliptical wound when tension released
• Elliptical wounds close with less tension and better cosmesis

Step 5: Punch Technique

• Apply punch perpendicular to skin surface
• Apply downward pressure with steady rotation in ONE direction
• Twist like a corkscrew (not back-and-forth - this shreds collagen)
• Continue until "give" is felt (entering subcutis)
• Withdraw punch carefully

Step 6: Specimen Removal

• Lift core gently with toothed forceps at deep edge (not crushing diagnostic tissue)
• Snip base with iris scissors at level of subcutis
• Handle specimen with minimal manipulation

Step 7: Haemostasis and Closure

• Apply pressure or cautery for haemostasis
• Close with simple interrupted suture (or allow secondary intention for ≤3mm)
• Evert wound edges for optimal healing

Step 8: Specimen Handling

• Place immediately in appropriate medium:
  • Formalin for routine H&E
  • Michel's medium for direct immunofluorescence
  • Fresh/saline for culture or special studies
• Ensure proper labelling

Technical Pearls

One-Direction Twist: Twisting the punch back-and-forth shreds collagen fibres and creates crush artefact, potentially rendering histology uninterpretable. Always twist in one direction only.

Perilesional DIF: For bullous disease, the DIF specimen must come from perilesional UNINVOLVED skin (within 1cm of blister but not blistered). Blister fluid destroys antibodies.

The 10% Rule: Formalin volume should be at least 10x the tissue volume for adequate fixation.

Complications

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7. Technique: Incisional Biopsy

Definition and Indications

Incisional biopsy removes a representative portion of a larger lesion without attempting complete excision. It provides full-thickness tissue for diagnosis when complete excision is not practical or desirable initially. [3,16]

Indications

Technique

Step 1: Planning

• Mark ellipse at junction of abnormal and normal tissue (lesion edge)
• For tumours: sample the most representative area (avoid necrotic centre)
• For panniculitis: include subcutaneous fat in specimen

Step 2: Ellipse Design

• Minimum 3:1 length-to-width ratio
• Align long axis with RSTLs
• Typically 1-2 cm length, 3-5 mm width

Step 3: Procedure

• Anaesthetize with field block
• Incise with No. 15 blade perpendicular to skin
• Dissect ellipse to appropriate depth (often into subcutis)
• Undermine if needed for closure

Step 4: Closure

• Layered closure with deep absorbable sutures and superficial non-absorbable
• Ensure eversion of wound edges

Panniculitis-Specific Considerations

• Must include subcutaneous fat to depth of at least 1 cm
• Standard punch biopsy is often inadequate
• Incisional or deep excisional biopsy preferred
• Specimen must be oriented and handled carefully to preserve fat lobule architecture

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8. Technique: Excisional Biopsy

Definition and Indications

Excisional biopsy removes the entire lesion with a peripheral margin of clinically normal tissue. This is the gold standard for suspected melanoma and provides both diagnostic and therapeutic benefit. [4,5,6,17]

Mandatory Indications

Margin Guidelines for Initial Excision

Ellipse Design Principles

The 3:1 Rule:

• Length-to-width ratio of 3:1 prevents "dog ears"
• On tight skin (scalp, shin), 4:1 ratio may be needed
• Smaller ratios cause standing cones at ellipse ends

Orientation:

• Align long axis with RSTLs (Langer's lines)
• On face: follow wrinkle lines
• Scar will contract along wound axis

Calculating Ellipse Dimensions:

• If lesion is 6mm diameter with 2mm margins:
• Width = 6mm + 2mm + 2mm = 10mm
• Length = 10mm × 3 = 30mm (minimum)

Equipment Required

• Sterile marking pen
• Antiseptic solution
• Lidocaine with adrenaline (field block)
• No. 15 scalpel blade (or No. 10 for larger lesions)
• Toothed forceps, scissors, needle holder
• Suture material (deep absorbable + superficial non-absorbable)
• Orientation suture (if required)
• Formalin specimen container
• Skin hooks (optional, for retraction)

Procedure: Step-by-Step

Step 1: Consent and Marking

• Explain scar, infection, bleeding, possibility of wider excision if melanoma
• Mark ellipse with sterile pen including margins
• Photograph lesion if appropriate

Step 2: Anaesthesia

• Perform field block around (not into) the ellipse
• Wait for full effect (vasoconstrictive action of adrenaline)

Step 3: Incision

• Hold scalpel perpendicular to skin surface
• Cut along marked lines in single smooth strokes
• Maintain consistent depth throughout
• Blade angle prevents bevelling (which causes incomplete margins)

Step 4: Excision

• Undermine specimen at level of subcutis
• Use scissors or scalpel for dissection
• Maintain even plane of dissection
• Lift specimen with skin hook or forceps (at edge, not centre)

Step 5: Haemostasis

• Achieve meticulous haemostasis with electrocautery or ties
• Reduce haematoma risk (especially in anticoagulated patients)

Step 6: Specimen Orientation

• Place orientation suture at 12 o'clock position
• Mark on histology form: "Suture at 12 o'clock = superior"
• Essential for margin assessment in melanoma and positive-margin re-excision

Step 7: Closure

Key Technical Points:

• Close deep layer first to take tension off wound
• Evert skin edges (slightly raised) - they will flatten
• Avoid tight sutures (cause ischaemia and suture marks)
• Space sutures 3-5mm apart

Step 8: Dressing

• Apply Steri-strips perpendicular to incision
• Cover with non-adherent dressing
• Consider pressure dressing if bleeding risk

Dog Ear Correction

Cause: Ellipse too short (ratio less than 3:1) or tissue redundancy

Correction Technique:

1. Identify standing cone at ellipse end
2. Undermine around the cone
3. Lay skin flat and mark excess as triangle (Burow's triangle)
4. Excise triangle
5. Close primarily

Prevention: Always design ellipse with adequate length-to-width ratio

Complications

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9. Specimen Handling and Transport

Transport Media Selection

Critical Errors to Avoid

Histology Request Form Requirements

Every request must include:

1. Patient demographics: Full name, DOB, hospital number
2. Specimen site: Precise anatomical location
3. Clinical description: Size, colour, texture, duration
4. Clinical history: Relevant medical history, medications
5. Clinical differential diagnosis: Top 2-3 possibilities
6. Specific questions: "Is this invasive?" "Are margins clear?"
7. Special requests: Immunohistochemistry, DIF, special stains

Sample Documentation

Specimen: 4mm Punch Biopsy Right Upper Arm
Clinical Description: 2cm erythematous scaly plaque, 6-month history
Clinical History: 45F, no significant PMH, family history of psoriasis
Clinical Differential: 1. Psoriasis 2. Eczema 3. Mycosis fungoides
Questions for Pathologist: Inflammatory pattern? Evidence of lymphocyte atypia?

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10. Anticoagulation Management

Evidence-Based Approach

Continuing anticoagulation for minor skin surgery is supported by systematic review evidence. The bleeding risk is manageable with appropriate technique, while stopping anticoagulation carries thromboembolic risks. [18,19]

Anticoagulant/Antiplatelet Management

Haemostasis Strategies for Anticoagulated Patients

1. Use adrenaline-containing local anaesthesia (vasoconstriction)
2. Meticulous surgical haemostasis (electrocautery for all bleeding points)
3. Pressure dressing post-procedure
4. Absorbable deep sutures to obliterate dead space
5. Elevate limb if lower extremity
6. Avoid NSAIDs post-operatively
7. Patient education: apply pressure if bleeding occurs

When to Refer for Specialist Input

• INR > 4.0
• Multiple anticoagulants/antiplatelets
• Recent thromboembolic event (less than 3 months)
• Mechanical heart valve
• Large excision (> 2cm) on anticoagulation
• High bleeding risk anatomical sites (scalp, face)

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11. Special Situations

Bullous Disease Biopsy Protocol

For suspected autoimmune bullous disease (Bullous Pemphigoid, Pemphigus Vulgaris, Dermatitis Herpetiformis):

Two Biopsies Required:

Critical Points:

• DIF MUST be from uninvolved skin adjacent to blister
• Blister fluid destroys immunoglobulins
• Michel's medium (NOT formalin) for DIF specimen
• Label pots clearly to avoid mix-up [11,12]

Vasculitis Biopsy

• Requires deep tissue to visualize blood vessel walls
• Use large punch (4-6mm) or small incisional biopsy
• Sample fresh lesions (less than 48 hours old) - older lesions lose diagnostic features
• Palpable purpura is the target lesion
• Include subcutaneous fat if possible

Melanoma-in-Situ (Lentigo Maligna)

• Edges often ill-defined on sun-damaged skin
• Multiple "scouting punches" may be taken around clinical edge
• Maps the true extent of disease before definitive staged excision
• Staged excision (slow Mohs) or Wood's lamp assessment may be needed

Alopecia Biopsy

Technical tip: Two punches allow horizontal sectioning of one (for follicular count) and vertical sectioning of other (for inflammation pattern).

Paediatric Considerations

• Topical anaesthesia (EMLA/LMX) applied 45-60 minutes prior
• Consider intranasal midazolam or oral sedation for anxious children
• Smaller punch sizes (2-3mm) often sufficient
• Absorbable sutures preferred (avoid suture removal)
• Careful site selection for cosmesis

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12. Complications and Management

Intraoperative Complications

Post-operative Complications

Wound Infection Risk Factors

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13. Post-Procedure Care

Patient Instructions

First 24-48 Hours:

• Keep dressing clean and dry
• Take paracetamol for discomfort (avoid NSAIDs - increase bleeding)
• Elevate site if on limb
• Avoid strenuous activity

After 48 Hours:

• May shower gently; pat dry
• Keep wound covered until sutures removed
• Avoid swimming, baths, saunas until healed

Suture Removal Timing:

Warning Signs (Seek Medical Attention):

• Increasing redness, warmth, or swelling around wound
• Purulent discharge or pus
• Fever
• Bleeding that doesn't stop with 10 minutes of firm pressure
• Wound opening (dehiscence)

Written Aftercare Information

Provide written instructions including:

1. Wound care instructions
2. Expected healing timeline
3. Activity restrictions
4. Warning signs
5. Contact information for concerns
6. Follow-up appointment details

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14. Histology Interpretation

Understanding the Dermatopathology Report

Common Histological Patterns

Direct Immunofluorescence Patterns

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15. Common Pitfalls and Medicolegal Issues

Critical Errors

Documentation Standards

Every procedure note should include:

1. Indication: Why biopsy performed
2. Consent: Documented discussion of risks and alternatives
3. Site: Precise anatomical location
4. Technique: Type of biopsy, punch size, or excision dimensions
5. Anaesthetic: Type, volume, with/without adrenaline
6. Findings: Macroscopic appearance of lesion
7. Specimen: Where sent, which medium
8. Closure: Suture type and number
9. Complications: Any intraoperative issues
10. Follow-up: Plan for review and results

Sample Procedure Note

PROCEDURE NOTE

Date: [Date]
Procedure: 4mm Punch Biopsy Left Shin
Indication: 6-month history of persistent scaly erythematous plaque, ? psoriasis vs. eczema
Consent: Verbal consent obtained. Risks (bleeding, infection, scar) discussed. Patient understands.
Anaesthetic: 1mL Lidocaine 2% with Adrenaline 1:100,000 infiltrated locally.
Procedure: Site prepped with chlorhexidine. 4mm punch biopsy performed using one-directional 
           technique. Core removed intact with toothed forceps at base (no crush). 
           Haemostasis achieved with pressure.
Closure: Single 4-0 Nylon simple interrupted suture.
Specimen: Sent in 10% buffered formalin to Dermatopathology.
Complications: None.
Post-op: Wound care advice given. Review with histology in 2 weeks. Suture removal in 14 days.

Signed: Dr [Name], [Date]

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16. Examination Scenarios

Viva Scenario 1: Pigmented Lesion

Stem: 45-year-old woman with a 6mm irregularly pigmented lesion on her back. Dermoscopy shows irregular network and blue-white veil. What biopsy?

Model Answer:

"This lesion has dermoscopic features concerning for melanoma, specifically the irregular network and blue-white veil. The appropriate biopsy technique is complete excision with a 2mm clinical margin.

Shave biopsy is absolutely contraindicated as it would prevent accurate Breslow depth measurement, which is essential for staging and determining the subsequent wide local excision margin.

I would orient the specimen with a suture at 12 o'clock to allow the pathologist to identify margins for potential re-excision. If melanoma is confirmed, the Breslow depth will determine the WLE margin: 1cm for ≤1mm, 1-2cm for 1-2mm, and 2cm for > 2mm."

Viva Scenario 2: Inflammatory Rash

Stem: 70-year-old man with a persistent scaly red plaque on face, present for 2 years. Clinical differential is Bowen's disease vs. SCC vs. psoriasis. What biopsy?

Model Answer:

"For this well-defined plaque with differential diagnosis including neoplastic (Bowen's, SCC) and inflammatory (psoriasis) conditions, I would perform a 4mm punch biopsy.

This provides full-thickness tissue allowing assessment of:

• Depth of invasion (if SCC)
• Presence of in-situ vs. invasive disease
• Inflammatory pattern (if psoriasis)

I would take the biopsy from the active edge of the lesion, avoiding any central ulceration. If histology confirms invasive SCC, definitive excision with 4-6mm margins would follow."

Viva Scenario 3: Bullous Disease

Stem: 65-year-old presents with tense blisters on limbs and trunk. You suspect Bullous Pemphigoid. How many biopsies and from where?

Model Answer:

"For suspected Bullous Pemphigoid, I would take two separate biopsies:

1. Lesional biopsy: 4mm punch from the edge of a fresh blister, placed in formalin for H&E. This will show subepidermal blister with eosinophils.

2. Perilesional biopsy: 4mm punch from uninvolved skin within 1cm of a blister (not blistered skin), placed in Michel's transport medium for Direct Immunofluorescence. This will show linear IgG and C3 at the basement membrane zone.

It is critical that the DIF specimen comes from perilesional non-blistered skin, as blister fluid destroys immunoglobulins. Formalin must NOT be used for DIF specimens."

Viva Scenario 4: Anticoagulated Patient

Stem: Patient on Warfarin (INR 2.8) needs a punch biopsy for a rash. What do you do?

Model Answer:

"I would proceed with the biopsy. An INR of 2.8 is within acceptable range (less than 3.5) for minor skin surgery.

My haemostatic strategy would include:

• Using lidocaine with adrenaline for vasoconstriction
• Electrocautery or aluminium chloride for haemostasis
• Pressure dressing post-procedure
• Suture closure rather than secondary intention

Current evidence supports continuing anticoagulation for minor skin procedures as the thromboembolic risk of stopping anticoagulation outweighs the manageable bleeding risk with appropriate technique."

Viva Scenario 5: Crush Artefact

Stem: FY2 doctor takes a punch biopsy but the pathology report says "Crush artefact. Uninterpretable."

Model Answer:

"Crush artefact occurs when the specimen is damaged during removal, typically by squeezing the diagnostic tissue with forceps.

The correct technique is:

• Use toothed forceps (not smooth)
• Grasp the specimen at the deep edge (subcutaneous fat), not the diagnostic dermis
• Handle with minimal compression
• Use one-directional twisting of the punch to avoid shredding collagen

The biopsy would need to be repeated using proper technique. This represents a preventable error that delays diagnosis and subjects the patient to an additional procedure."

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17. Training Competency Framework

Expected Skill Progression

Assessment Criteria

Competence should be assessed against:

1. Knowledge: Indications, contraindications, anatomy, complications
2. Technical skill: Smooth technique, tissue handling, closure quality
3. Decision-making: Appropriate technique selection for lesion type
4. Communication: Consent, explanation, post-procedure instructions
5. Documentation: Complete and accurate procedure notes
6. Professionalism: Preparation, aseptic technique, equipment familiarity

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18. Patient/Layperson Explanation

What is a Skin Biopsy?

A skin biopsy is a simple procedure where a small sample of your skin is taken and examined under a microscope. This helps doctors find out what is causing a rash, lump, or skin change.

Types of Skin Biopsy

• Shave biopsy: A thin layer is shaved from the surface (like shaving off a raised mole)
• Punch biopsy: A small circular sample is taken (like using a tiny cookie cutter)
• Excision biopsy: The entire lump is removed with a small border of normal skin

Does it Hurt?

You will receive an injection of local anaesthetic (the same kind dentists use). The injection stings briefly, but after that the area is numb and you should feel no pain during the procedure.

Will it Leave a Scar?

There will be a small scar. The size depends on the type of biopsy. Most scars heal very well and fade significantly over several months. Your doctor will position the cut to minimize scarring.

How Long Does it Take?

The procedure takes about 5-15 minutes. You can go home immediately afterwards.

Aftercare

• Keep the wound clean and dry for 48 hours
• Take paracetamol if needed for discomfort
• Follow the wound care instructions provided
• Attend for suture removal if needed (usually 5-14 days depending on location)
• Watch for signs of infection: increasing redness, swelling, pus, or fever

When Will I Get Results?

Usually 1-2 weeks. Your GP or specialist will contact you with the results and discuss any further treatment needed.

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19. Evidence and Guidelines

Key Guidelines

Evidence Summary

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20. References

1. Nischal U, Nischal Kc, Khopkar U. Techniques of skin biopsy and practical considerations. J Cutan Aesthet Surg. 2008;1(2):107-111. doi:10.4103/0974-2077.44174

2. Alguire PC, Mathes BM. Skin biopsy techniques for the internist. J Gen Intern Med. 1998;13(1):46-54. doi:10.1046/j.1525-1497.1998.00009.x

3. Pickett H. Shave and punch biopsy for skin lesions. Am Fam Physician. 2011;84(9):995-1002. PMID: 22046940

4. Ng JC, Swain S, Dowling JP, Wolfe R, Simpson P, Kelly JW. The impact of partial biopsy on histopathologic diagnosis of cutaneous melanoma: experience of an Australian tertiary referral service. Arch Dermatol. 2010;146(3):234-239. doi:10.1001/archdermatol.2010.14

5. Swetter SM, Tsao H, Bichakjian CK, et al. Guidelines of care for the management of primary cutaneous melanoma. J Am Acad Dermatol. 2019;80(1):208-250. doi:10.1016/j.jaad.2018.08.055

6. Saco M, Thigpen J. A retrospective comparison between preoperative and postoperative Breslow depth in primary cutaneous melanoma: how preoperative shave biopsies affect surgical management. J Drugs Dermatol. 2014;13(5):531-536. PMID: 24809875

7. Brantsch KD, Meisner C, Schönfisch B, et al. Analysis of risk factors determining prognosis of cutaneous squamous-cell carcinoma: a prospective study. Lancet Oncol. 2008;9(8):713-720. doi:10.1016/S1470-2045(08)70178-5

8. Lalonde D, Bell M, Benoit P, Sparkes G, Denkler K, Chang P. A multicenter prospective study of 3,110 consecutive cases of elective epinephrine use in the fingers and hand: the Dalhousie Project clinical phase. J Hand Surg Am. 2005;30(5):1061-1067. doi:10.1016/j.jhsa.2005.05.006

9. Thomson CJ, Lalonde DH, Denkler KA, Feicht AJ. A critical look at the evidence for and against elective epinephrine use in the finger. Plast Reconstr Surg. 2007;119(1):260-266. doi:10.1097/01.prs.0000237039.71227.11

10. Ilicki J. Safety of epinephrine in digital nerve blocks: a literature review. J Emerg Med. 2015;49(5):799-809. doi:10.1016/j.jemermed.2015.06.025

11. Mutasim DF, Adams BB. Immunofluorescence in dermatology. J Am Acad Dermatol. 2001;45(6):803-824. doi:10.1067/mjd.2001.117518

12. Vodegel RM, Jonkman MF, Pas HH, de Jong MC. U-serrated immunodeposition pattern differentiates type VII collagen targeting bullous diseases from other subepidermal bullous autoimmune diseases. Br J Dermatol. 2004;151(1):112-118. doi:10.1111/j.1365-2133.2004.06006.x

13. Linos E, Katz KA, Colditz GA. Skin cancer—the importance of prevention. JAMA Intern Med. 2016;176(10):1435-1436. doi:10.1001/jamainternmed.2016.5008

14. Borges AF. Relaxed skin tension lines (RSTL) versus other skin lines. Plast Reconstr Surg. 1984;73(1):144-150. doi:10.1097/00006534-198401000-00036

15. Elston DM, Stratman EJ, Miller SJ. Skin biopsy: Biopsy issues in specific diseases. J Am Acad Dermatol. 2016;74(1):1-16. doi:10.1016/j.jaad.2015.06.033

16. Scolyer RA, Thompson JF, McCarthy SW, et al. Incomplete biopsy of melanocytic lesions can impair the accuracy of pathological diagnosis. Australas J Dermatol. 2006;47(1):71-75. doi:10.1111/j.1440-0960.2006.00230.x

17. Morton DL, Thompson JF, Cochran AJ, et al. Final trial report of sentinel-node biopsy versus nodal observation in melanoma. N Engl J Med. 2014;370(7):599-609. doi:10.1056/NEJMoa1310460

18. Shimizu I, Jellinek NJ, Engel S, Engel ER. Anticoagulant and antiplatelet agent use in dermatologic surgery. Dermatol Surg. 2019;45(10):1226-1244. doi:10.1097/DSS.0000000000001837

19. Lewis KG, Dufresne RG Jr. A meta-analysis of complications attributed to anticoagulation among patients following cutaneous surgery. Dermatol Surg. 2008;34(2):160-165. doi:10.1111/j.1524-4725.2007.34035.x

20. Bordeaux JS, Martires KJ, Goldberg D, Pattee SF, Fu P, Maloney ME. Prospective evaluation of dermatologic surgery complications including patients on multiple antiplatelet and anticoagulant medications. J Am Acad Dermatol. 2011;65(3):576-583. doi:10.1016/j.jaad.2011.02.012

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Medical Disclaimer: MedVellum content is for educational purposes and clinical reference. Clinical decisions should account for individual patient circumstances. This does not replace supervised training for procedures.