Testicular Germ Cell Tumors with Somatic-type Malignancy

Abstract

Testicular cancer accounts for ∼1% of all cancers in men worldwide, with over 90% of testicular cancers being germ cell tumors (GCTs). Since the introduction of multimodal therapy, testicular GCTs have been among the most curable solid tumors. However, some patients may develop late relapse, which is defined as recurrence at least two years after the initial complete remission. Late recurrence is particularly common in patients with teratomatous GCTs and is associated with somatic-type malignancy (SM) development. Approximately 2.5–8.0% of testicular GCT patients may develop SM, a distinct secondary component that resembles cancers seen in other organs and tissues. The histological subtypes of SM are diverse and may show morphological features of sarcomas, carcinomas, embryonic-type neuroectodermal tumors, nephroblastomas, hematologic malignancies, or a combination of different forms. Several studies have demonstrated that the development of SM in testicular GCTs, particularly at metastatic sites, is associated with a poor prognosis. In the current review, we discuss the concept of GCTs with SM, the diagnostic criteria, the common histological subtypes, the pathogenesis, and the clinical outcomes of GCT patients with SM.