Sentinel lymph node identification in the staging of cutaneous melanoma. Blue dye vs. radioguided localization

BACKGROUND: The purpose of this study is to emphasize the usefulness of combined intraoperative gamma-detecting-probe (C-Trak) and blue dye guided research of sentinel nodes (SN) in the treatment of cutaneous melanoma. METHODS: At the Department of General Surgery of Macerata Hospital, after informed consent, 22 consecutive patients (10 males and 12 females) with mean age 53 years (20-78 years) affected by histologically proved cutaneous malignant melanoma in stage I (TC, ultrasonography and bone scintigraphy) were studied by dynamic lymphoscintigraphy with 10.8-22.2 MBq of 99mTc albumin microcolloids 18-22 hours before surgery and by intradermal injection of blue dye at induction of anaesthesia. Intraoperative mapping technique to localize SN has been done by using a combination of a vital blue dye and a radioactive tracer. RESULTS: A total of 42 SN were identified. Micrometastases were found in 2 (9.1%) patients; 13 SN were well-coloured (31%), 23 SN were poorly-coloured (55%), and 6 SN were not coloured (14%). Overall localization with blue dye was 86%. All SN were radiolabeled, but identification with gamma detecting probe was possible only in 41 cases (95%). Combined techniques was effective in 100% of cases. CONCLUSIONS: Combined use of radiocolloids and blue dye is the gold standard for correct identification and biopsy of SN with 100% of favourable results. The technique is simple, fast and effective and permits to select the patients that need other surgical and oncologic procedures.