Morton 2014 - NEJM - SLNB melanoma
Jing Qin Tay
9/26/2023
Summary
The Multicenter Selective Lymphadenectomy Trial (MSLT-I) compared outcomes of sentinel lymph node biopsy versus observation for patients with intermediate thickness (1.2-3.5mm) or thick (>3.5mm) cutaneous melanomas. 2001 patients were randomized to wide excision plus sentinel lymph node biopsy, with immediate lymph node dissection if positive (biopsy group), or wide excision plus observation, with delayed lymph node dissection for nodal recurrence (observation group).
After 10 years follow-up, there was no difference in melanoma-specific survival between groups for either thickness. However, disease-free survival was significantly improved with sentinel node biopsy for both thicknesses. Among biopsy patients, sentinel node status powerfully predicted prognosis - positive nodes had far worse melanoma survival versus negative nodes.
20.8% of patients overall had nodal metastases. For node-positive patients with intermediate thickness melanomas, immediate lymph node dissection with positive sentinel biopsy significantly improved 10-year melanoma-specific survival (62.1% vs 41.5% with observation/delayed dissection) and distant metastasis-free survival. There was no survival difference for node-positive thick melanoma patients based on timing of lymph node dissection.
In summary, sentinel lymph node biopsy provides important prognostic information and may improve regional disease control and survival for intermediate thickness melanoma patients with occult node metastases. These long-term data support use of sentinel node biopsy for staging and guiding management of intermediate thickness melanomas.