In 2010, the National Comprehensive Cancer Network (NCCN) recommended sentinel lymph node biopsy (SLNB) for thin melanomas ≤1 mm with mitotic rate (MR) ≥1. In 2016, the criteria were changed to Breslow depth >0.75 mm and MR ≥1.OBJECTIVE
To compare the impact of 2010 and 2016 NCCN guidelines on SLNB case selection and thin melanoma outcomes.MATERIALS AND METHODS
Ten-year retrospective cohort of primary thin melanomas at an academic hospital was retroactively stratified for SLNB eligibility using the 2010 and 2016 NCCN guidelines. Nodal recurrence-free survival (NRFS) and disease-free survival (DFS) were compared.RESULTS
Eight hundred two patients with 859 tumors and median follow-up of 79 months were included. Eleven percent fewer tumors qualified for SLNB under 2016 versus 2010 NCCN guidelines (19% vs 8%, p < .001). The 2016-qualifying cases also had lower 10-year NRFS (70.7% vs 95.2%, p < .001) and DFS (64.7% vs 91.4%, p < .001). Among 2016-qualifying cases, those that received SLNB had improved NRFS (85.6% vs 35.3%, p = .001) and DFS (80.2% vs 30.5%, p < .001) as compared to those that did not receive SLNB.CONCLUSION
The 2016 NCCN guidelines reduced the number of thin melanomas qualifying for SLNB and more accurately selected cases with higher risks of nodal recurrence and death.