Description
Tissue polypeptide specific antigen was first identified as a tumour marker in the late 1950's, and has recently been shown to be closely related to human cytokeratin 18. Cytokeratins are a group of about 20 cytoskeletal proteins, whose degradation gives rise to soluble fragments, measurable in the blood of patients. Serum levels are high in breast cancer patients and also some other malignancies, probably due to high cell turnover in tumours