Sentinel Lymph Node Biopsy for Desmoplastic Melanoma: A Systematic Review and Meta-analysis

Area of Science:

• Dermatology
• Surgical Oncology
• Pathology

Background:

• The role of sentinel lymph node biopsy (SLNB) in desmoplastic melanoma (DM) is debated due to its metastatic potential and diagnostic challenges differentiating pure from mixed subtypes.
• Uncertainty exists regarding the clinical utility of SLNB for DM staging.

Purpose of the Study:

• To evaluate pooled SLNB positivity rates in patients with DM, analyzing differences between pure and mixed histologic subtypes.
• To clarify the diagnostic value of SLNB in DM management.

Main Methods:

• A systematic review and random-effects meta-analysis of 18 studies involving 1671 patients with DM.
• Inclusion criteria focused on studies reporting SLNB positivity rates, excluding large registry-based studies.
• Subgroup analysis was performed to compare SLNB positivity rates between pure and mixed DM subtypes.

Main Results:

• The overall pooled SLNB positivity rate for DM was 9% (95% CI, 7-12%).
• No significant association was observed between SLNB positivity and Breslow depth or ulceration.
• Pooled SLNB positivity rates were 6% (95% CI, 4-8%) for pure DM and 15% (95% CI, 10-20%) for mixed DM.

Conclusions:

• SLNB may offer significant prognostic and diagnostic benefits for patients with mixed DM.
• Selective consideration of SLNB in pure DM is advised, especially when histopathologic uncertainty or other high-risk features are present.