Lymphatic mapping in management of patients with primary cutaneous melanoma.

In patients with primary cutaneous melanoma, knowledge of regional lymph-node status provides important information on outlook. Evidence suggests that early removal of nodes that contain metastatic disease improves survival outcome. Lymphatic drainage occurs first to sentinel nodes, which are therefore the nodes most likely to contain metastatic disease. Lymphatic mapping with lymphoscintigraphy is important to identify reliably sentinel nodes for removal and thus establish the status of regional nodes. Mapping studies in patients with melanoma have provided new insights into lymphatic anatomy and have shown previously unsuspected drainage pathways, which have important implications for accurate identification and removal of sentinel nodes. Because it is impossible to predict the site or sites of sentinel nodes clinically in individual patients, routine preoperative lymphoscintigraphy is a prerequisite if reliable results are to be obtained from sentinel-node biopsy.