Surgical Management of Spitzoid Melanoma
For spitzoid melanoma, perform wide local excision with 1 cm margins and strongly consider sentinel lymph node biopsy for lesions ≥1 mm in thickness, as these lesions demonstrate high rates of nodal involvement but excellent long-term outcomes with appropriate staging and regional disease control. 1
Initial Surgical Excision
**Excision margins should be 1 cm for all atypical and malignant spitzoid lesions in young children (<14 years), regardless of measured thickness.** 1 For older children and young adults, apply standard thickness-based margins: 1 cm for lesions ≤1.0 mm, 1-2 cm for 1.01-2.0 mm lesions, and 2 cm for lesions >2.0 mm. 1, 2
The rationale for uniform 1 cm margins in younger children stems from the diagnostic uncertainty inherent to these lesions and the excellent outcomes observed with this approach—no local recurrences have been documented with this strategy. 1
Role of Sentinel Lymph Node Biopsy
Sentinel lymph node biopsy should be routinely performed for spitzoid melanomas ≥1 mm in thickness when melanoma cannot be excluded. 1 This recommendation differs from the approach to atypical Spitz tumors of uncertain malignant potential, where the role of SLNB remains more controversial.
Key Evidence Supporting SLNB in Spitzoid Melanoma:
High nodal positivity rates: Studies demonstrate 30-87.5% positive sentinel node rates in spitzoid melanomas, substantially higher than conventional melanomas. 3, 4, 5
Excellent prognosis despite nodal involvement: Pediatric patients with positive sentinel nodes and spitzoid melanoma show 100% survival rates with appropriate regional disease control, suggesting these lesions have different biological behavior than conventional melanoma. 4
Staging and treatment guidance: SLNB provides critical staging information that guides decisions about completion lymphadenectomy and adjuvant therapy, and facilitates clinical trial enrollment. 1, 6
Technical Considerations:
Timing is critical: Perform SLNB before or concurrent with wide local excision to avoid disrupting lymphatic drainage patterns. 2
Standard SLNB technique applies: Use radiocolloid and dye injection with standard mapping procedures as for conventional melanoma. 6, 7
Management of Positive Sentinel Nodes
Completion lymph node dissection is recommended for all patients with positive sentinel nodes. 1, 6 This achieves regional disease control, though additional positive nodes are found in only 25% of completion dissections in spitzoid melanoma. 4
All node-positive cases should be managed analogously to adult melanoma, including consideration of adjuvant systemic therapy. 1, 4 In the pediatric spitzoid melanoma series, 5/8 SLNB-positive patients received adjuvant therapy with excellent long-term outcomes. 4
Critical Diagnostic Caveat
The prognostic significance of nodal metastases in spitzoid lesions differs fundamentally from conventional melanoma. 5, 8 Nodal involvement does not convey the same poor prognosis, and there appears to be limited ability for progression within the nodal basin. 5 This biological difference means SLNB serves primarily as a staging tool rather than a definitive prognostic indicator.
When to Exercise Caution:
For diagnostically controversial atypical Spitz tumors (not definitively melanoma), the use of SLNB is more contentious. 8, 9 Some experts discourage SLNB in these cases due to peculiar biological properties and risk of diagnostic confusion. 8 However, when melanoma is strongly suspected or cannot be excluded, proceeding with SLNB provides valuable staging information. 1, 9
Pathologic Evaluation Requirements
Ensure accurate pathologic reporting including the number and status of tumor-positive nodes, as recommended by the College of American Pathologists. 6 Given the diagnostic challenges with spitzoid lesions, consider review by experienced dermatopathologists, as even experts may disagree on classification. 5, 9