Evaluating Variation in Lymph Node Sampling During Sentinel Lymph Node Biopsy for Melanoma.

Area of Science:

• Oncology
• Surgical Oncology
• Cancer Staging

Background:

• The Commission on Cancer (CoC) operative standard for melanoma lacks SLNB data, unlike breast cancer standards.
• Sentinel lymph node biopsy (SLNB) is crucial for melanoma nodal staging.
• This study assessed facility-level variation in nodal yield and positivity for melanoma SLNB.

Purpose of the Study:

• To characterize facility-level variation in nodal yield for melanoma SLNB.
• To determine variation in nodal positivity for melanoma SLNB.
• To identify opportunities for standardization in melanoma SLNB.

Main Methods:

• Analysis of National Cancer Database (2018-2022) for melanoma patients (T1b-T4) of the trunk and upper extremities undergoing SLNB.
• Reliability-adjusted estimates for nodal yield and positivity calculated.
• Poisson and logistic regression with random intercepts used for hospital-level analysis.

Main Results:

• 48,653 melanoma patients from 1167 facilities were analyzed.
• Median nodal yield was 2.4 (IQR 2.2-2.7), with facility range 1.4-7.0.
• Median nodal positivity was 18.0% (IQR 17.1-19.5%), with facility range 11.6-40.5%.

Conclusions:

• Facility-level variation in melanoma SLNB nodal yield was minimal and weakly correlated with nodal positivity.
• Melanoma SLNB appears well-standardized across CoC hospitals without a specific operative standard.
• Future quality improvement efforts may target lymphadenectomy or novel dissection approaches.