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 met astases, if present, always are found first in the SN. The aim of this stud y was to determine the reliability of this procedure by establishing the su ccess 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 s tage I and II cutaneous melanoma underwent SN biopsy by a triple technique. Preoperatively, all patients underwent (dynamic) lymphoscintigraphy. A gam ma probe and blue dye helped localize the SN(s) during surgery, and these n odes subsequently were excised. These lymph nodes were step-sectioned and e xamined by routine and immunohistochemical staining. If the SN contained tu mor 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 foll ow-up, without simultaneous appearance of (locoregional) metastases. Conclusions: With a 99% success rate and a 1.5% rate of failed SN procedure s (7% false-negative rate) after a median follow-up of 3.5 years, we conclu ded that the combined triple technique approach of detecting the SN was a r eliable method to accurately identify and retrieve the SN.