Polysialylated neural cell adhesion molecule in childhood ganglioneuroma and neuroblastoma of different histological grade and clinical stage

Background and aims: Neuroblastoma cells ex press the polysialylated form of the neural cell adhesion molecule (PSA-NCAM), which normally becomes restricted to a few neural regions after embryogenesis. The aim of the present study was to evaluate PSA-NCAM as a marker in childhood neuroblastoma. Patients/methods: We studied the expression of PSA-NCAM on tumor specimens and in sera of 27 children, altogether, with ganglioneuroma and neuroblastoma of different histological grades and clinical stages. For both methods, immunohistochemistry on 5-mu m frozen sections and immunoluminescence serum assay, the polysialic-acid-specific monoclonal antibody 735 was used. Results: PSA-NCAM expression was highest in patients with undifferentiated neuroblastoma and advanced stages of disease, whereas children with differentiated tumor types and low clinical stages had distinctly reduced or no reactivity in immunohistochemistry and, simultaneously, normal serum levels. PSA-NCAM expression correlated with other prognostic and diagnostic markers, such as MYCN gene amplification, and serum concentrations decreased during successful treatment. Conclusions: We conclude that PSA-NCAM, both immunohistochemically and in the serum, is a promising candidate for another useful diagnostic and prognostic tumor marker in childhood neuroblastoma.