Tumor markers for metastatic
melanoma have, so far, been infrequently used. Although there is good evidence from several studies that
protein S-100B serum measurement could serve as a valid marker for micro- and/or macrometastasis, the S-100B-LIAmat test has not been established as part of national and international recommendations for the care of
melanoma patients. Future studies should focus on early detection of metastatic disease with S-100B compared to routine clinical, laboratory and technical evaluations. Furthermore, preliminary, interesting results on the predictive value of S-100B for the monitoring of metastatic patients during treatment should be verified in multicenter trials. The same considerations are true for
melanoma-inhibitory activity (MIA), a new and interesting tool for the detection of metastatic
melanoma. However, available data on the clinical use of on the MIA-ELISA are too limited to speculate on an even higher sensitivity and specificity than reported for S-100B.
Melanin metabolites are candidates for valid
melanoma markers, too. Quantification of
5-S-cysteinyldopa from blood or urine of
melanoma patients has not been transferred from the laboratory to daily routine due to several technical problems in the assessment of this particular molecule.
Cytokines, adhesion molecules and
metalloproteinases are shed from
melanoma cells into the serum, but these cells are not the only source of elevated serum levels. Several inflammatory conditions are responsible for high serum concentrations of these molecules. In general, they are not sensitive and specific enough to serve as "
melanoma markers."