Serum tumour markers in germ cell tumours: From diagnosis to cure

Germ cell tumors (GCTs) represent the best and the only example of solid tumors curable in the large majority of patients. GCTs are one of the few malignancies for which specific biochemical markers have been identified: human chorionic gonadotropin (HCG) and alfa-fetoprotein (AFP). Due to their specificity and sensitivity they constitute formidable tools in the diagnosis and monitoring of treatment for GCTs. As a tumor mass marker, lactate dehydrogenase (LDH) is also considered. Tumor markers are expressed in 15–20% of seminoma and 60–80% of non-seminoma. With the aim to increase sensitivity and specificity, recent studies have proposed miRNAs as serum biomarkers. This review will focus on role of serum tumor markers in diagnosis, staging, prognosis, monitoring of response, and finally follow-up of GCTs.