SINGLE-INJECTION GAMMA-PROBE-GUIDED SENTINEL LYMPH-NODE DETECTION IN 40 MELANOMATOUS LYMPHADENECTOMIES

The aim of the study was to evaluate single-injection gamma probe-guid ed sentinel lymph node (SLN) detection, applied in 40 melanomatous sel ective sentinel lymphadenectomies (SSLNDs). Thirty-four patients under went preoperative lymphoscintigraphy, intraoperative SLN identificatio n by a gamma-detecting probe and blue dye, and SLN sampling. The first 11 patients underwent formal lymphadenectomy, The following 23 patien ts underwent formal lymphadenectomy only when the SLN was involved wit h tumor, Evaluation included hematoxylin-eosin-stained slide microscop y, monoclonal antibodies to S-100 protein, and the melanoma-associated antigen HMB45. In all patients, single or multiple SLNs were identifi ed by the gamma-detecting probe. However, only 82.5% of these specimen s included blue-stained nodes. None of the non-SLN specimens were the exclusive site of metastases. Four patients had metastases in their SL N specimen without non-SLN involvement. We conclude that SSLND can be performed easily and precisely with the exclusive use of the gamma-det ecting probe, A single injection is feasible, and decreases operating room contamination and patient discomfort.