Reliability of the sentinel node procedure in melanoma patients: Analysis of failures after long-term follow-up

Background: The sentinel node (SN) concept assumes that early lymphatic metastases, if present, always are found first in the SN. The aim of this study was to determine the reliability of this procedure by establishing the success rate and number of failed procedures during a follow-up period of at least 2 years. Methods: From August 1993 to November 1996, 204 consecutive patients with stage I and II cutaneous melanoma underwent SN biopsy by a triple technique. Preoperatively, all patients underwent (dynamic) lymphoscintigraphy. A gamma probe and blue dye helped localize the SN(s) during surgery, and these nodes subsequently were excised. These lymph nodes were step-sectioned and examined by routine and immunohistochemical staining. If the SN contained tumor cells, a lymphadenectomy was performed at a later date. Results: The median follow-up time was 42 months. The success rate was 99%. Three patients developed a recurrence in the negative SN basin during follow-up, without simultaneous appearance of (locoregional) metastases. Conclusions: With a 99% success rate and a 1.5% rate of failed SN procedures (7% false-negative rate) after a median follow-up of 3.5 years, we concluded that the combined triple technique approach of detecting the SN was a reliable method to accurately identify and retrieve the SN.