The role of elective lymph node dissection in malignant melanoma: who should undergo this nodal staging procedure?

The issue of elective lymph node dissection (ELND) is probably one of the most important controversies in the management of patients with melanoma. The debate is perhaps coming to a close because the results of the Intergroup Melanoma Surgical Trial have shown significant improvement in subgroups of patients based on age and melanoma thickness. In addition, increasing applicability of intraoperative lymphatic mapping and sentinel lymph node (SLN) biopsy in the surgical treatment of the patient with melanoma provides a more conservative approach to the regional basin. Historically, three randomized prospective studies did not demonstrate any survival advantage for ELND but three nonrandomized studies involving melanomas from all anatomic sites showed a statistically significant improvement in survival for the subgroup of patients with intermediate thickness melanomas. Although there is unanimous opinion that all melanoma patients do not need ELND, there is still a continuing debate that centers around two issues: (1) Is it possible to identify accurately a subgroup of melanoma patients at high risk for microscopic regional nodal metastases and a low enough risk of occult systemic metastases to justify a regional node procedure? and (2) What is the optimal timing of dissection (immediate versus delayed) if such a highrisk group can be identified? Prospective randomized studies have recently been completed to help resolve this issue. SELECTION OF PATIENTS