Survival varies widely in Stage III melanoma. The existence of clinical significance for positive NSLN status would warrant consideration for incorporation into the AJCC staging system and better prediction of survival.

The objective of this study was to evaluate whether disease limited to the sentinel lymph node (SLN) represents different clinical significance than disease spread into nonsentinel lymph nodes (NSLN).

Our database was queried for all patients with positive SLN for cutaneous melanoma who subsequently underwent completion lymph node dissection.

Disease-free, melanoma-specific, and overall survival

4,223 patients underwent SLN biopsy from 1986–2012. 329 patients had a tumor positive SLN. 250 (76%) had no additional positive nodes. 79 (24%) had a positive NSLN. Factors predictive of NSLN positivity included older age (p=0.04), thicker breslow (p<0.0001), and ulceration (p<0.015). Median overall survival (OS) was 178 months for the SLN+ only group and 42.2 months for the NSLN+ group (5-yr OS, 72.3% and 46.4% respectively.) Median disease-specific survival (DSS) was not reached for the SLN+ only group and was 60 months for the NSLN+ group (5-yr DSS 77.8% and 49.5% respectively.) On multivariate analysis, NSLN positivity had a strong association with recurrence, {HR: 1.754 (1.228–2.505); p=0.002}, shorter OS {HR: 2.24 (1.476–3.404); p=0.0002} and shorter DSS {HR: 2.225 (1.456–3.072); p<0.0001}. To further control for the effects of total positive nodes, comparison was done for those with N2 disease only (2–3 total positive LN), this confirmed the independent effect of NSLN status (DSS; p=0.04).

NSLN positivity is one of the most significant prognostic factors in patients with Stage III melanoma. An AJCC sub classification of nodal stage based on NSLN positivity should be considered.