Efficacy and reproducibility of lymphatics mapping technique with sentinel lymph node biopsy in melanoma.

Introduction: The study of the Sentinel Lymph Node (SLN) in Melanoma is a procedure that aims the identification of the first node to which the affected cutaneous sector drains in order to avoid unnecessary lymphadenectomies. The present study documents the frequency of identification of SLN; the relationship between positive SLN (PSLN) and recurrence, between the Breslow index (BI) and PSLN, and between BI and disease recurrence.

Method: We analyzed the records of 148 patients with melanoma stages I and II undergoing lymphatic mapping and GC biopsy from 1999 to 2017 in a third level institution in Córdoba, Argentina. We performed preoperative lympho centellography, lymphatic mapping with combined technique and SLN biopsy. Postoperative controls were established in order to detect recurrences.

Results: SLN was identified in 145 patients (97.9%), being positive in 25 cases (17.2%). Recurrence was detected in 10 (8.3%) patients with negative SLN (NSLN), and in 2 (9.09%) with PSLN (p = 0.188). The median BI was 2 mm in PCG patients and 1.2 mm in GCN patients (p = 0.002). The mean BI in patients with recurrence was 2.77 mm, and 2.01 mm in those who did not show relapse (p = 0.311).

Conclusions: The combined technique allows a high GC identification rate. A greater tendency to recurrence was observed in the presence of CPG. A statistically significant relationship between GCP and IB was found. The GC technique is effective and replicable in our environment.