The role of peptides and their receptors as tumor markers.

This article focuses on the role of peptides and peptide receptors as in vitro and in vivo markers for several human malignancies. Neuroendocrine or similar neoplasms can produce excessive quantities of peptides, which may be used as diagnostic markers. Recent studies demonstrate that several tumor types express excessive amounts of peptide receptors, which also may be considered as potentially valuable tumor markers. The considerable progress made in the field of peptide receptors in oncology, ranging from test-tube work in the laboratory to challenging diagnostic possibilities in the clinic, is reviewed in detail with particular emphasis on the peptide somatostatin and its receptors.