Predictive factors for false negative sentinel lymph node in melanoma patients

BACKGROUND Sentinel lymph node biopsy (SLNB) represents a useful tool for staging melanoma patients. However false-negative SLNB are reported in the literature. OBJECTIVE The aim of our study is to identify predictive factors for false-negative SLNB in melanoma patients. MATERIALS AND METHODS We conducted a retrospective analysis on 316 melanoma patients who underwent SLNB and were followed up at the Department of Dermatology and Plastic Surgery of University of Rome “Sapienza” from March 1994 to June 2008. RESULTS In our patients, SLNB was positive in 35 cases (11.07%) whereas it was negative in 281 cases (88.93%); 12/316 patients (3.8%) had positive SLNB and positive therapeutic lymph node dissection (TLND); 23/316 (7.28%) patients had positive SLNB and negative TLND; 266/316 (84.18%) patients had negative SLNB but without subsequent metastases in the SLN site; 15/316 (4.74%) patients had negative SLNB, but with subsequent metastases in the same SLN site (false-negative patients). Among the different prognostic factors, only ulceration was the main predictive factor for false-negative SLNB, according to statistical analysis (p=.0420). CONCLUSION Our data confirm that SLNB is a useful technique for staging melanoma patients. However, in patients with negative SLNB, a closer follow-up is recommended when ulceration is present. The authors have indicated no significant interest with commercial supporters.