Primary therapy of malignant melanomas: sentinel lymphadenectomy.

BACKGROUND: Each melanoma is drained by one or, occasionally, several individual lymph nodes within the nearest lymph node region (sentinel lymph node). OBJECTIVE: By histopathologic examination of the removed sentinel lymph node (SLN), it is possible to select patients clinically according to stage I or II (UICC classification), but who, microscopically, represent stage III. METHODS: Sentinel lymphadenectomies (SLNEs) were performed initially by the vital blue dye technique, and later by gamma-probe guidance only. The removed SLNs were examined by hematoxylin and eosin as well as immunohistochemical stains (S100, and HMB 45). RESULTS: We have performed 115 gamma-probe-guided SLNEs in 100 patients. The SLN could be found in all cases. In pT3 + 4 melanomas, 27.5% of the SLNs were positive; in only one patient with a pT2 tumor were micrometastases found. CONCLUSIONS: gamma-Probe-guided SLNE is a reliable procedure with minimal complications that should be performed in all pT3 + 4 (intraoperative frozen section histology) melanomas without clinically evident metastases.