Is sentinel lymph node mapping indicated for isolated local and in-transit recurrent melanoma?

To determine the feasibility of sentinel lymph node mapping in local and in-transit recurrent melanoma. The accuracy of intraoperative lymphatic mapping and sentinel lymphadenectomy (LM/SL) for identification of occult lymph node metastases is well established in primary melanoma. We hypothesized that LM/SL could be useful to detect regional node metastases in patients with isolated local and in-transit recurrent melanoma (RM). Review of our prospective melanoma database of 1600 LM/SL patients identified 30 patients who underwent LM/SL for RM. Patients with tumor-positive sentinel nodes (SNs) were considered for completion lymph node dissection. Of the 30 patients, 17 were men and 13 were women; their median age was 57 years (range, 29-86 years). Primary lesions were more often on the extremities (40%) than the head and neck (33%) or the trunk (8%). At least 1 SN was identified in each lymph node basin that drained an RM. Of the 14 (47%) patients with tumor-positive SNs, 11 (78%) underwent complete lymph node dissection; 4 had tumor-positive non-SNs. The median disease-free survival after LM/SL was 16 months (range, 1-108 months) when an SN was positive and 36 months (range, 6-132 months) when SNs were negative. At a median follow-up of 20 months (range, 2-48 months), there were no dissected basin recurrences after a tumor-negative SNs. LM/SL can accurately identify SNs draining an RM, and the high rate of SN metastases and associated poor disease-free survival for patients with tumor-positive SN suggests that LM/SL should be routinely considered in the management of patients with isolated RM.