Testis

Abstract

The testis is not a common specimen. Resections in children or young adults may be due to a non-neoplastic condition such as torsion, which produces the relatively nonspecific picture of hemorrhage and/or ischemic necrosis. There are also a few tumors that typically only occur in children. Most testicular tumors occur in men in their 20s–40s, although they also occur in the elderly. The vast majority of testicular tumors are of germ cell origin. The remainder, aside from lymphoma, are tumors of mesothelial, epithelial, or connective tissue origin which will not be covered here. Germ cell tumors, which include seminoma, teratoma, yolk sac tumor, choriocarcinoma, and embryonal carcinoma, can all occur as pure tumors in and of themselves, but they do have a tendency to collide in adults, with the resulting mixture called a mixed germ cell tumor (MGCT). This chapter will review the most common tumors of the testis, including the reclassified spermatocytic tumor.