Recommended Margins for Melanoma Excision

Margin Recommendations Based on Breslow Thickness

The National Comprehensive Cancer Network recommends a 0.5-1 cm margin for melanoma in situ, with increasing evidence supporting 1 cm margins, particularly for head and neck lesions 1, 4
The American College of Surgeons recommends a 1 cm margin for melanomas ≤1 mm thick, which is a category 1 recommendation based on high-level evidence 1, 2, 3, 5
For melanomas 1.01-2 mm thick, a 1-2 cm margin is recommended, with multiple randomized trials showing no difference in local recurrence, disease-free survival, or overall survival between 1 cm and wider margins 1
The National Comprehensive Cancer Network recommends a 2 cm margin for melanomas >2 mm thick, which is a category 1 recommendation based on high-level evidence 1, 4

In anatomically sensitive locations, such as the face or distal extremities, margins may be modified to accommodate individual anatomic or cosmetic considerations 1
For lentigo maligna melanoma, staged excision techniques or Mohs micrographic surgery may be appropriate, particularly on the head and neck, with a 95.1% clearance rate and only 0.5% recurrence 4, 1

Clinical/surgical margins do not necessarily correlate with histological margins, so careful pathological assessment is essential 1

Inadequate margins for lentigo maligna can lead to high recurrence rates, particularly on the head and neck 4, 1
Using narrower margins than recommended for thick melanomas may lead to higher rates of melanoma-specific mortality 1
Overlooking tumor regression can lead to inadequate margins, and consideration should be given to using margins for the category immediately above the actual thickness 2, 3, 5