Evaluation and Management of a Mole
Any mole that exhibits asymmetry, border irregularity, color heterogeneity, recent evolution (change in size, color, or elevation), or appears as an "ugly duckling" (different from other moles on the patient) should undergo complete excisional biopsy with a 1-3 mm margin of normal skin to establish definitive diagnosis 1, 2.
Clinical Evaluation
Warning Signs Requiring Urgent Referral
Use the ABCDE criteria to identify suspicious lesions 1, 2:
- Asymmetry in shape
- Border irregularity
- Color heterogeneity (multiple colors within one lesion)
- Dynamics/evolution (recent changes in size, color, elevation)
- Note: Many melanomas today are <5 mm in diameter, so size alone should not provide false reassurance 1
The "ugly duckling" concept is equally important: melanomas often look different from a patient's other nevi, standing out as dissimilar 1, 2.
Additional Concerning Features
- Itching or bleeding 3
- New mole appearing after puberty that is changing 3
- Long-standing mole with new changes 3
- Three or more colors within a single lesion 3
- New pigmented line in a nail with associated nail damage 3
Enhanced Diagnostic Tools
Dermoscopy by an experienced physician enhances diagnostic accuracy and should be used when available 1, 2. However, dermoscopy should only be performed by clinicians trained in the technique, as accuracy depends heavily on experience 4.
Diagnostic Approach
Biopsy Technique
Perform complete excisional biopsy—never partial biopsy or destructive methods 4:
- Excise the entire lesion with 1-3 mm margin of normal skin using a scalpel 4, 5
- Use elliptical incision with long axis parallel to skin lines to facilitate potential re-excision 4
- Ensure full-thickness excision extending deep enough to avoid transecting the lesion at the base 5
- Never use laser, electrocautery, or cryotherapy—these destroy tissue needed for accurate diagnosis 4
- Never perform frozen section analysis 4
Critical pitfall: Partial biopsies risk misdiagnosis and inaccurate staging, which can negatively affect treatment planning 4, 5. The entire lesion must be examined to assess maximum thickness (Breslow depth), which is the most important prognostic factor.
Pathology Requirements
The histopathology report must include 1, 2:
- Maximum tumor thickness in millimeters (Breslow depth, to nearest 0.1 mm)
- Presence of ulceration
- Mitotic rate
- Surgical margin clearance
- Clark level of invasion
- Presence and extent of regression
- Melanoma subtype (superficial spreading, nodular, lentigo maligna, acral lentiginous)
Management of Benign Moles
Observation vs. Removal
Most benign moles require only observation—prophylactic removal of all atypical moles is neither necessary nor cost-effective 6, 7.
Remove moles when they have:
- Features suggesting malignant transformation (ABCDE criteria) 6
- Documented change on serial photography or dermoscopy 8
- Patient concern with documented evolution 3
High-Risk Patients Requiring Surveillance
Patients at moderately increased risk (8-10× general population) 3:
- Previous melanoma
- Large numbers of moles with some clinically atypical features
- Organ transplant recipients
Patients at greatly increased risk (>10× general population) 3:
- Familial atypical mole and melanoma syndrome (>50 atypical moles + ≥2 family members with melanoma) 6
- Giant congenital pigmented nevus
Management for high-risk patients 3, 6, 7:
- Counsel about sun avoidance and monthly skin self-examination
- Annual total body skin examination by experienced clinician
- Consider total body photography and sequential digital dermoscopy for monitoring 8
- Screen family members 6
- Begin surveillance around puberty and continue lifelong 7
Key Clinical Pitfalls
- Do not rely on size alone: Many melanomas are <5 mm diameter 1
- Do not perform shave or punch biopsies of suspected melanomas—full excision is mandatory 4, 5
- Do not delay excision for dermoscopy or photography if clinical suspicion is high 3
- Do not assume young age or professional status indicates better awareness—these groups often show the most risky behavior and least knowledge about melanoma 9
- Document incision orientation carefully to avoid compromising future wide excision if melanoma is diagnosed 4