Defining the highway of lymphatic patterns for melanoma.

摘要

In 1892, Herbert Snow advocated wide excision and elective lymph-node dissection (ELND) to control lymphatic permeation of melanoma metastases. His studies suggested a connection between primary skin tumours and regional lymph nodes, indicating that treatment of melanoma should routinely include excision of these nodes. Through most of the next century, regional lymph-node dissection was usually based on anatomical landmarks alone. Most of the descriptions of lymphatic drainage patterns were attributed to Sappey, who suggested that the vertical meridian through the torso and horizontal axis through the umbilicus defined four quadrants, each with separate drainage to the axilla or groin lymph-node basins. While retrospective studies were done to validate Snow's observations as to the importance of ELND, none of the randomised trials studying this procedure have shown a survival advantage of ELND. The apparent absence of therapeutic benefit from ELND, in part, relates to the relatively small number of patients with intermediate thickness melanoma with tumour-positive lymph nodes (about 20%) and perhaps to the inherent