Sentinel lymph node detection with lymphoscintigraphy and intraoperative probe in malignant melanoma patients

BACKGROUND: The sentinel lymph node is the first node in a lymphatic basin to receive lymphatic drainage from a tumor site. If this node is free of tumor, then radical lymphadenectomy may be avoided. The goal of this study was to assess the usefulness of lymphoscintigraphy and intraoperative gamma probe in the sentinel node detection in patients with malignant melanoma. METHOD: We prospectively studied 40 patients with malignant melanoma (24 in I/II stages and 16 in III stage). The day before surgery a lymphoscintigraphy with Tc-99m-nanocolloid was performed and the first lymph node identified was considered as sentinel node. For intra-operative mapping a hand-held gamma probe was used. RESULTS: Sentinel nodes were identified in 39/40 (97.5%) patients. In 24 patients with I/II stages 34 sentinel nodes were demonstrated (six positive and 28 negative for malignant melanoma). A total amount of 161 regional lymph nodes was harvested, all of them being negative for malignant melanoma. In 16 patients with III stage, 22 sentinel nodes were located (14 positive and eight negative for malignant melanoma). A total of 89 regional lymph nodes were excised in sentinel nodes positive patients (44 positive and 45 negative for malignant melanoma) and 36 lymph nodes in sentinel node negative, all of them negative for malignant melanoma. CONCLUSIONS: In patients with malignant melanoma, lymphoscintigraphy with Tc-99-nanocolloid is useful for the detection of sentinel lymph node. Biopsy of this node is useful for the selection of patients to undertake a lymphadenectomy.