Effect of multiple-nodal basin drainage on cutaneous melanoma

The number of nodal basins draining a primary cutaneous melanoma is not an independent predictor of outcome.

Post hoc analysis of patients entered into a randomized, prospective study.

Multi-institutional academic and community medical centers.

Patients aged 18 to 70 years with melanoma 1.0 mm or greater Breslow thickness.

Wide local excision and sentinel lymph node biopsy were performed on all patients; patients with sentinel lymph node metastases underwent completion lymphadenectomy. Patients with multiple-nodal basin drainage were compared with those with single-nodal basin drainage.

Sentinel lymph node status, locoregional recurrence-free survival, disease-free survival, and overall survival.

A total of 2060 patients with single-nodal basin drainage (n = 1709 [83% of cohort]) were included in the analysis, with a median follow-up of 50 months. On univariate analysis, the group with multiple-nodal basin drainage (n = 351) was associated with female sex and primary tumor regression (P < .001). In addition, multiple-nodal basin drainage was associated with truncal primary tumor location (73.2%), while single-nodal basin drainage was more common for extremity tumors (50.9%; P < .001). On multivariate analysis, there were no differences in the rate of sentinel lymph node metastasis, disease-free survival, or overall survival between the groups. Interestingly, locoregional recurrence was significantly worse in the single-nodal basin drainage group (P = .003).

Multiple-nodal basin drainage does not confer a worse prognosis for patients with cutaneous melanoma. In fact, single-nodal basin drainage appears to be associated with a greater risk of locoregional recurrence.