Serum sialic acid is a biologic marker for malignant disease

Serial serum sialic acid (N-acetylneuraminic acid) was measured in 16 patients with advanced cancer of various histologic types. In the 15 evaluable patients serial changes in sialic acid correlated with the clinical course. Isolated sialic acid values were not predictive of clinical response. Serial determination of serum sialic acid appears to be a useful monitor of tumor burden.