Comparison of classification systems in melanoma sentinel lymph nodes--an analysis of 697 patients from a single center.

BACKGROUND: In melanoma, different classification systems have been proposed that predict overall survival (OS) and recurrence-free survival (RFS) based on findings in the sentinel lymph node (SLN). The authors of this report compared the RFS and OS of 697 melanoma patients as predicted by various classification systems.
METHODS: The Rotterdam system (based on the greatest dimension of the largest tumor cell deposit), the Augsburg S-classification (based on tumor penetrative depth [TPD]), and the Hannover system (based on a combination of tumor load, TPD, and invasion of the capsule) were studied in 697 consecutive melanoma patients who underwent SLN biopsy at the authors' center.
RESULTS: In univariate analyses, the Rotterdam and Hannover systems (but not the S-classification) identified 1 group of SLN-positive patients that had OS and RFS similar to the OS and RFS of SLN-negative patients. The intermediate groups from all classification systems did not differ significantly with regard to RFS and/or OS from the adjacent groups. In multivariate analysis using a Cox model, the greatest dimension of the largest tumor cell deposit (cutoff point, <0.1 mm vs > or = 0.1 mm), the TPD (cutoff point, < or = 2 mm vs > 2 mm), and capsular involvement represented independent parameters for RFS; and TPD and capsular involvement also were independent parameters for OS. On the basis of these 3 parameters, a new scoring system for risk assessment in patients with melanoma is proposed that can distinguish 3 separate groups of patients that differed significantly in OS and RFS.
CONCLUSIONS: Different parameters of independent prognostic significance were identified in SLNs from patients with melanoma. Combining these parameters, the prognosis of patients with melanoma was predicted more precisely by the new scoring system than by currently published classification systems.