Early recurrence after lymphatic mapping and sentinel node biopsy in patients with primary extremity melanoma: a comparison with elective lymph node dissection.

INTRODUCTION: Although sentinel node biopsy with completion lymphadenectomy in node-positive patients (SLND) has been widely adopted in the management of patients with early stage melanoma, reports detailing the outcome of patients after SLND are limited. To address this issue, we analyzed our experience with SLND and provided a comparison to patients treated with elective lymph node dissection (ELND).
METHODS: All patients who underwent SLND (1991-1998) and ELND (1974-1994) were identified from single institution melanoma databases.
RESULTS: A total of 152 and 329 patients with early-stage melanoma of the extremity underwent SLND and ELND, respectively. Nodal metastases were present in 44 of 329 ELND patients (13%) and in 31 of 152 SLND patients (20%). Early relapse-free and disease-specific survivals were similar for the entire population, although in patients at higher risk for recurrence (age >50 years, thickness >3.0 mm), there was an increased rate of relapse in the SLND group (P = .04). Among all sites of early recurrences, locoregional sites were more common in patients undergoing SLND (72%) compared with ELND (39%, P < .01). SLN-negative patients with nodal recurrence had evidence of metastases on retrospective enhanced pathologic analysis in four of seven cases.
CONCLUSIONS: Although overall relapse-free and disease-specific survivals are similar, there is a higher rate of relapse in a subset of SLND node-negative patients who are at high risk for nodal metastases. ELND and SLNB should not be thought of as equivalent approaches until studies with longer follow-up are available.