Significance of multiple nodal basin drainage in patients with truncal melanoma.

Background: Assessing whether an association exists between drainage to multiple basins and lymphatic metastasis in patients with truncal melanoma (TM).

Methods: The study included 260 patients with primary TM (163 men; median age 56.5 y/o) with a cN0 M0, who underwent a sentinel lymph node scintigraphy and biopsy. The median tumor thickness (TT) was 1.51 mm.

Results: One hundred and three patients showed more than one basin; of these, 95 patients had 2 basins, 6 had 3 basins, and 2 had 4 basins of drainage. Nodal histology was positive for metastatic disease in 65 patients, of whom, 40 had 1 basin, 24 had 2 basins and 1 had 3 basins of drainage. Of the 195 node-negative patients, 116 had 1 basin, 70 had 2 basins, 5 had 3 basins, and 2 had 4 basins of drainage (P=0.89). In a median follow-up of 36 months, 26 patients showed progressive disease, of whom 15 had 1 basin and 11 had 2 basins (P=0.76). Twenty patients died, of whom 11 had 1 basin and 9 had 2 basins (P=0.8).

Conclusions: There is no significant association between the number of drainage basins and sentinel node positivity or further progress of the disease in patients with TM.