S100B protein detection in serum is a significant prognostic factor in metastatic melanoma

The serum detection of S100B, a new melanoma marker, has shown clinical sig nificance in early studies. The aim of our study of 1,339 serum samples fro m 412 different melanoma patients and 107 control patients was to prove the prognostic value of serum S100B levels in melanoma patients at different s tages of disease and at follow-up (median: 30 months). Using a cutoff level of 0.2 mu g/I S100B, 5 of 286 patients (1.7%) with primary tumors (stage I /II), 14/73 (19.2%) patients with locoregional metastasis (stage III) and 5 7/84 (67.9%) patients with advanced disease (stage IV) were S100B positive (statistically significant differences for stage I/II vs, III, I/II vs. IV, and III vs. IV, p < 0.001). The estimated overall survival time was signif icantly longer (p < 0.001)for patients with S100B values below 0.2 mu g/I c ompared to patients with elevated S100B levels (greater than or equal to 0. 2 mu g/I), which was independent of the stage of disease (I-IV). Regarding prognosis, we were furthermore able to distinguish different subgroups amon g stage III and IV patients using S100B serum levels (p < 0.01). Patients w ith different cutaneous non-melanoma diseases served as S100B-negative cont rols. S100B serum evaluations using the Sangtec(R)100 IRMA are highly speci fic and sensitive for the detection of metastatic melanoma. S100B has been shown to be a relevant prognostic factor for survival in a study with a lar ge sample site of melanoma patients including close follow-up evaluations.