Theoretical and empirical arguments in relation to elective lymph node dissection for melanoma

Nearly a century of clinical inquiry has failed to incontrovertibly resolve the question of whether elective lymph node dissection is therapeutically beneficial in the management of clinically localized melanoma. The controversy has been renewed by a recent interim update from the Intergroup Melanoma Surgical Program, sponsored by the National Cancer Institute, which has indicated a small survival benefit in a narrowly defined subgroup of patients with primary melanoma. That report stimulated this review of the data, which are presented in the historical context that originally prompted the Intergroup study. Case selection bias has intractably hindered firm conclusions from the numerous nonrandomized studies of elective lymphadenectomy. The two original randomized trials that were executed during the 1970s failed to uncover any significant effect of the procedure on survival. Definitive conclusions from the recent Intergroup report are limited by the likelihood that the observed therapeutic benefits are a chance occurrence resulting from uncorrected multiple subgroup comparisons. It remains uncertain whether elective lymphadenectomy can be therapeutically beneficial in the management of melanoma. Nevertheless, it is clear that the procedure, or preferably sentinel lymphatic mapping with selective lymphadenectomy, can provide clinically relevant prognostic information, as well as the staging data requisite to adjuvant interferon alfa-2b therapy or enrollment into other adjunctive trials for patients at high risk of clinical relapse.