Prognostic value of sentinel lymph node biopsy compared with that of Breslow thickness: implications for informed consent in patients with invasive melanoma.

Background: Sentinel lymph node (SLN) status is reportedly a powerful prognosticator of survival. Breslow thickness alone provides significant prognostic information.

Objective: To assess overall survival (OS) according to tumor depth based on SLN status.

Materials And Methods: MEDLINE, EMBASE, and the Cochrane Central Database were searched for studies. Included studies evaluated overall survival according to SLNB results and were stratified according to Breslow thickness. Meta-analysis was performed if appropriate in each category for which three or more studies reported risk estimates and variability measurement.

Results: Twenty-nine articles met inclusion criteria. Six met the criteria for meta-analysis. In individuals with thin melanoma (<1 mm), SLN-negative status conferred no survival advantage (sign test, p > .99). Few studies were available for intermediate depths, and most reported worse survival in SLN-positive patients, although the difference was not statistically significant (p > .05). For thick melanoma (>4 mm), SLN positivity was related to worse prognosis (sign test, p = .004). Based on the pooled results of six studies of patients with tumors 4 mm thick or thicker, SLN-positive patients had a greater likelihood of dying (hazard ratio = 2.42, 95% confidence interval = 2.00-2.92).

Conclusions: Sentinel lymph node biopsy may not provide more-accurate prognostic information than Breslow thickness for most melanomas.