What are the recommended management and prevention strategies for a patient with multiple nevi (moles) on the face, considering risk factors for skin cancer?

Management of Multiple Facial Nevi

Patients with multiple nevi on the face require dermatology referral for comprehensive evaluation, regular surveillance with visual inspection and palpation, strict sun protection, and patient education on self-monitoring for concerning changes. 1

Immediate Risk Stratification

The first step is determining whether these are congenital melanocytic nevi (CMN) or acquired nevi, as this fundamentally changes management:

For Congenital Melanocytic Nevi (Present at Birth)

All patients with multiple CMN should be referred to dermatology within days to weeks for proper evaluation and risk assessment. 2, 3 The key risk factors that elevate melanoma risk include:

• Projected adult size >40 cm for any single nevus 1, 2
• ≥10 satellite lesions (historically >20 was the threshold, but newer recommendations suggest >1 CMN warrants heightened surveillance) 1
• Trunk location (may be a proxy for larger size) 1
• Multiple medium-sized CMN without a largest CMN (distinct high-risk presentation) 1

The melanoma risk in multiple CMN can reach 8%, with the majority presenting in the central nervous system rather than the skin. 1, 2 This is critical because CNS melanomas are often fatal and require different surveillance strategies.

For Acquired Nevi (Developed After Birth)

Patients with ≥100 total nevi are at moderately increased melanoma risk (approximately 8-10 times baseline). 1 However, the USPSTF found insufficient evidence to recommend routine screening in asymptomatic adults, even those with multiple nevi. 1 Despite this, the UK guidelines recommend that patients with large numbers of moles, particularly if some are clinically atypical, should be counseled about their risk and taught self-examination. 1

Surveillance Protocol

For Multiple Congenital Melanocytic Nevi

Follow every 3 months during the first year of life due to the highest risk period for melanoma development in infancy. 1, 2 After the first year, gradually decrease to at minimum annual dermatology evaluation for life. 1

At each visit:

• Perform visual inspection using dermoscopy (increases diagnostic accuracy in trained hands) 1
• Palpate all CMN - this is critical because melanoma in CMN can present as deep dermal or subcutaneous nodules without overlying color change 1, 2, 4
• Palpate regional lymph nodes in higher-risk patients 1
• Serial photography (both close-up and distant) to document changes over time 1, 2

For Multiple Acquired Nevi

Annual dermatology evaluation is appropriate for patients with numerous acquired nevi. 1 More frequent monitoring (every 3-6 months) is warranted if nevi are changing or if the patient has additional risk factors like family history of melanoma or personal history of dysplastic nevi. 1

Neuroimaging for High-Risk Patients

Patients with multiple medium CMN, ≥10 satellite lesions, or giant CMN should undergo screening MRI of the brain and spine. 1, 2 This screens for neurocutaneous melanosis (NCM), which carries a 12% melanoma risk compared to 2% without NCM. 1

Early MRI screening without contrast or anesthesia in young infants is preferred to decrease procedural risks while providing useful clinical information. 1 Approximately 79% of screened patients show normal findings, 10% have intraparenchymal melanosis, and the remainder have other findings. 2

Solitary small, medium, and large CMN are low risk for NCM and MRI screening is not recommended unless neurologic signs or symptoms develop. 1

Patient Education on Warning Signs

Between visits, patients or caregivers must visually inspect and palpate all nevi and report concerning changes immediately. 1, 4 Red flags requiring prompt dermatology evaluation include:

• Rapid or asymmetric growth beyond expected proportional growth with body size 2, 3
• Color variation or heterogeneous darkening 2, 3
• Development of nodules or papules, particularly deep palpable nodules 1, 2, 3
• Bleeding, ulceration, or persistent erosions 1, 2, 3
• Pain or significant pruritus 2, 3

For acquired nevi, use the ABCDE rule: Asymmetry, Border irregularity, Color variation, Diameter >6mm, and Evolution over time. 1

Sun Protection and Prevention

All patients with multiple facial nevi require counseling on strict UV protection: 1

• Broad-spectrum sunscreen application
• Protective hats and clothing
• Seeking shade
• Avoiding sun during peak hours (10 AM - 4 PM)
• Complete avoidance of indoor tanning beds 5

The USPSTF specifically recommends counseling children, adolescents, and young adults aged 10-24 years with fair skin about minimizing UV exposure. 1

Skin Care for Facial Nevi

Gentle skin care is essential to prevent irritation that could complicate surveillance: 1, 4

• Bathe with water alone or nonsoap cleanser 2-3 times weekly
• Apply bland, thick emollients (creams or ointments with minimal fragrances/preservatives)
• For acute eczematous flares, use low-to-mid-potency topical corticosteroids twice daily 1, 4

Intervention Considerations

Prophylactic removal of benign-appearing nevi is generally not recommended as the melanoma risk in most acquired nevi is extremely low. 6 However, removal may be considered for:

• Nevi with concerning features on examination
• Cosmetic concerns (particularly relevant for facial location)
• Nevi subject to chronic irritation

If removal is pursued, complete excisional biopsy is strongly preferred over shave biopsy to allow comprehensive histological assessment including depth evaluation. 2, 4, 3

Avoid ablative procedures (pigment-specific lasers, curettage, dermabrasion) as these obscure future melanoma evaluation and cause frequent pigment recurrence. 1, 2, 4, 3

Critical Pitfalls to Avoid

• Never assume growth or change is benign - melanoma in CMN can present as deep nodules without surface color change, making palpation essential 1, 2, 4
• Do not delay dermatology referral for multiple CMN, as early risk stratification and surveillance planning are crucial 2, 3
• Do not perform biopsies in primary care for suspicious lesions - clinicopathological correlation by specialists is vital for diagnostic accuracy 1
• Do not overlook the 4-8% risk of developing new primary melanomas in patients with a history of melanoma, typically within 3-5 years 1