RADIOGUIDED SURGERY FOR THE ULTRASTAGING OF THE PATIENT WITH MELANOMA

PURPOSE Lymphatic mapping techniques have changed the standard of surg ical care for the malignant melanoma population and are being investig ated to improve the staging and decrease the morbidity of patients wit h all types of cancer. This study aimed to describe a combination of t echniques and the use of multiple disciplines for accurately staging a nd treating patients with melanoma. MATERIALS AND METHODS Over a 4-yea r period, 595 patients were studied using a protocol consisting of pre operative lymphoscintigraphy using filtered technetium sulfur colloid to define all regional basins at risk for metastatic disease, and intr aoperative lymphatic mapping with a vital blue dye and radiocolloid to identify the node in the basin most at risk for metastases (the senti nel lymph node). Detailed pathological exam (serial sectioning, immuno histochemical staining, reverse transcriptase polymerase chain reactio n [RT-PCR] analysis) of the sentinel lymph node was used to stage the melanoma patient. RESULTS A combination of blue dye and radiocolloid i ntraoperative mapping resulted in a 98% success rate for the identific ation of the sentinel lymph node. Routine pathological examination ide ntified 73.8% of the metastases. The remainder were detected with seri al sectioning (7.8%) and immunohistochemical staining (18.4%). RT-PCR analysis based on a tyrosinase probe has upstaged 47% of the histologi c sentinel lymph node -negative population. CONCLUSION Lymphatic mappi ng technology provides accurate staging of the melanoma patient, at lo wer costs for the health care system and a lower morbidity for the pat ient.