Locoregional Lymph Node Recurrence of Trunk Melanoma in Non-sentinel Lymph Node Basins: An Observational Retrospective Study.

Locoregional lymph node recurrences of primary trunk melanoma can occur in basins not identified during sentinel lymph node biopsy. However, the factors associated with recurrences in non-sentinel lymph node basins are unknown. To evaluate these factors, this observational retrospective study examined the patterns of first lymph node recurrence and the factors associated with recurrence in non-sentinel lymph node basins. A total of 305 patients with primary trunk melanoma who had undergone sentinel lymph node biopsy from 2000 to 2015 were evaluated. Twenty-three patients presented locoregional lymph node recurrence; 8 of which (34.8%) were in non-sentinel lymph node basins. Non-sentinel lymph node recurrences were more frequent in patients with positive sentinel lymph nodes and in those patients whose number of tumour-involved nodes was > 3. These results suggest that clinical examination and ultrasound surveillance should be performed on all potential lymph node drainage basins of trunk melanomas.