What are the recommended procedures and considerations for removing a mole, particularly for a patient with potential cosmetic or cancer concerns and a history of skin cancer or atypical moles?

Mole Removal: Recommended Procedures and Considerations

For suspicious moles or those requiring removal, complete excisional biopsy with 2-5 mm margins and a cuff of fat is the standard approach, while prophylactic removal of benign-appearing moles is not recommended. 1, 2

When to Remove a Mole

Urgent Referral Criteria

Refer immediately to a dermatologist or specialist when any of the following are present: 1

• New mole appearing after puberty that is changing in shape, color, or size 1
• Long-standing mole with changes in shape, color, or size 1
• Three or more colors present or loss of symmetry 1
• Symptoms including itching or bleeding 1
• New pigmented line in a nail, especially with associated nail damage 1

When NOT to Remove

• Prophylactic excision of benign-appearing pigmented lesions or small congenital nevi without suspicious features is futile and not recommended 1, 3
• Over-the-counter mole removal creams should never be used, as they preclude histopathologic evaluation and can cause scarring 4, 5

Proper Removal Technique

For Suspicious Lesions (Possible Melanoma)

Complete excisional biopsy is mandatory: 1, 2

• Photograph the lesion before removal 1
• Excise the entire lesion with 2 mm clinical margin of normal skin 1
• Include a cuff of subcutaneous fat to allow accurate Breslow thickness measurement 1
• Orient the excision axis to facilitate possible future wide excision (typically along the long axis on limbs) 1

Critical Technical Errors to Avoid

Never perform the following for suspicious lesions: 1, 2

• Shave biopsies - these lead to sampling error and make accurate pathological staging impossible 1, 2
• Punch biopsies - same limitations as shave biopsies 1
• Partial removal - creates pseudomelanoma appearance, causing diagnostic confusion and needless anxiety 1, 2
• Incisional biopsy in primary care - only acceptable by specialists for specific situations like facial lentigo maligna 1, 3

For Atypical (Dysplastic) Nevi

Management depends on degree of atypia: 2, 6

• Mild to moderate atypia with positive margins after biopsy: Observation is acceptable, as local recurrence rates are minimal (3.6% over 2 years) and melanoma transformation risk is very low 6
• Severe dysplasia or solitary atypical nevus: Conservative re-excision with 2-5 mm margins is preferred 2, 6
• Multiple atypical nevi: Removing all is neither necessary nor cost-effective 7

Special Anatomic Considerations

Facial lesions (lentigo maligna): 3

• Incisional biopsy is acceptable for diagnosis 3
• Standard treatment is excision with 0.5 cm margin for in situ disease 1, 3
• Alternative options for elderly patients or when excision is contraindicated: radiotherapy, CO2 laser, or cryotherapy 1, 3

Subungual lesions: 1

• Must be performed by experienced surgeons 1
• Remove the nail and adequately sample the nail matrix 1

Margins for Confirmed Melanoma

If melanoma is confirmed on pathology, definitive excision margins depend on Breslow thickness: 1, 3

• <1 mm depth: 1 cm margin is safe 1, 3
• 1-2 mm depth: Minimum 1 cm margin, with 2 cm preferred where functionally and cosmetically sensible 1, 3
• 2-4 mm depth: 2 cm margins recommended 1, 3

High-Risk Patient Surveillance

Moderately Increased Risk (8-10x general population)

Includes patients with: 1

• Previous primary melanoma 1
• Large numbers of moles, some clinically atypical 1
• Organ transplant recipients 1

Management: Counsel about risk, teach monthly self-examination, but long-term follow-up is not usual 1

Greatly Increased Risk (>10x general population)

• Giant congenital pigmented nevi require long-term follow-up 1, 2
• Family history of 3+ melanomas or pancreatic cancer: Refer to clinical geneticist 1

Common Pitfalls

1. Using destructive methods (laser, electrodesiccation, over-the-counter creams) prevents histopathologic evaluation and may mask malignant transformation 4
2. Removing suspicious lesions in primary care - these should be referred to specialists for proper evaluation and removal 1
3. Inadequate specimen depth - failing to include subcutaneous fat prevents accurate Breslow thickness determination 1
4. Prophylactic removal of all atypical moles - this is neither clinically beneficial nor cost-effective 7, 8