Comparison Between Potential Blood Markers to Detect Metastatic Uveal Melanoma

Abstract

Purpose: : Serum Osteopontin levels have been shown to increase in metastatic uveal melanoma. This study was designed to compare Osteopontin, with two other potential serum markers for metastatic uveal melanoma: S–100 and MIA.

Methods: : Serum levels of Osteropontin, S–100 and MIA were examined in sera from 15 patients with proven metastatic uveal melanoma and of 37 patients under follow–up for more than 10 years without metastatic disease. Among the 15 patients with metastases, serum samples from 8 patients before and after the diagnosis of metastases were assayed. Serum from 30 healthy age– and sex–matched individuals were also examined as a control group for this part. The three biomarkers were measured by commercially available ELISA kits (Assay Designs, Ann Arbor, MI).

Results: : The serum levels of S100 protein were 2 fold higher in patients with metastatic melanoma to the liver than in the control disease–free population (Kruskal Wallis chi–square = 4.0859, df=1, p=0.0432), but there was no significant difference between serum levels in patients before and after metastasis (sign test, p=0.4531). Serum levels of MIA neither discriminated between patients with patient with metastatic melanoma and controls (Kruskal Wallis chi–square = 2.4210, df=1, p=0.1197), nor between patients before and after metastasis (sign test, p=0.7266).

Conclusions: : The nearly 2 fold increase in S–100 levels is of borderline significance. In this study MIA was not found to be a useful serum marker for metastatic uveal melanoma. Elevation in serum osteopontin remains the only serum marker tested among three common biomakers for melanoma that appears to identify patients with metastatic uveal melanoma to the liver.

Keywords: melanoma • oncology