S-100β protein - Serum levels in children with brain neoplasms and its potential as a tumor marker

Objective: To determine if serum S-100β levels are elevated in children with brain neoplasms and if it can be used as a tumor marker for children with brain neoplasms. Design: Prospective cohort study. Setting: Urban, tertiary care, children's teaching hospital. Patients: 136 healthy children and 27 children with brain neoplasms. Methods: Serum levels of S-100β were measured in 136 healthy children to serve as controls and 27 children with brain neoplasms, who underwent biopsy or resection of the mass. Patients were then classified into astrocytoma or non-astrocytoma groups. Measurements and main results: The median serum S-100β level for the control group was 0.27 mcg/l (range, 0.06-2.6 mcg/l), and for the brain neoplasm group was 0.2 mcg/l (range, 0.01-2.1 mcg/l), (p = 0.09). There were 13 children with astrocytomas and 14 with non-astrocytomas. The S-100β levels for the astrocytoma group was 0.25 mcg/l (range, 0.05-1.1 mcg/l) and for the non-astrocytoma group 0.17 mcg/l (range, 0.01-2.1 mcg/l), (p = 0.47). Conclusions: Serum S-100β levels are not elevated in children with brain neoplasms compared to healthy children, nor are they elevated in children with astrocytomas compared to non-astrocytomas. The S-100β protein does not appear to be useful as a serum tumor marker in children with brain neoplasms.