National practice patterns of completion lymph node dissection for sentinel node-positive melanoma

Background and Objectives: Close observation may be an appropriate alternative to completion lymph node dissection (CLND) for selected patient populations, especially those with minimal tumor burden in the sentinel lymph node (SLN). In this study, we examined the practice patterns of CLND utilization. Methods: Using the National Cancer Database, we examined CLND utilization in SLN-positive patients diagnosed with clinically node-negative Stage III melanoma from 2012 to 2015. Hierarchical logistic regression models were constructed to assess the factors associated with observation after positive SLN biopsy (SLNB). Results: Of the 131 171 patients identified, 55 688 (42.5%) underwent SLNB and 7200 (12.9%) had an SLN with a metastatic disease. CLND was performed in 57.0% of the patients with a positive SLNB. Patients were more likely to forgo CLND if the primary tumor was located on the lower extremity (odds ratio [OR], 1.65, 95% confidence interval [CI], 1.40-1.94), were older (P < 0.001), had multiple comorbidities (OR, 1.61, 95% CI, 1.19-2.20), or were diagnosed with melanoma in 2015 (OR, 1.33, 95% CI, 1.13-1.56 vs 2012). Conclusions: CLND utilization varied based on patient factors and decreased over time. As evidence supports close observation in selected patient populations with low SLN tumor burden, monitoring is needed to ensure that CLND is performed in the appropriate patient populations. However, this will require improvements in the data collected by cancer registries.