Chapter 7 - Liquid biopsy in male genital tract: Testis tumor

Abstract

Testis cancer is the most common solid tumor in the male population aged 15–35, which accounts for 20% of diagnosed malignancies in this age-group. The conventional serum tumor markers such as α-fetoprotein (AFP), β-subunit of human chorionic gonadotropin (β-hCG), and lactate dehydrogenase (LDH) for testicular cancer are increased in only 60% of the testicular germ cell tumors (GCTs). Moreover, these tumor markers do not show a rise in patients with pure teratoma. Therefore, other tumor markers are needed to improve diagnostic evaluation, prognosis evaluation, and recurrence monitoring in patients with testicular tumors to facilitate clinical treatment. Several clinical studies have implied the prognostic significance of detecting circulating tumor cells (CTCs), micro-RNAs, cell-free DNA, and epigenetic factors in these patients. Some of these studies have encouraging results. Even though liquid biopsy is a new entity in testicular cancer, it barges its way into diagnosing, treating, and monitoring GCTs. To date, serum micro-RNAs, especially miR-371-3p, have manifested promising results in these fields in numerous experiments. However, further investigations would be crucial to find novel markers and establish their role in various clinical aspects of patients with testicular cancers, more importantly, GCTs.