COMPARATIVE ANALYSIS OF TESTICULAR TUMORS IN MAN AND MAN’S BEST FRIEND

Abstract

Testicular cancer is the most common cancer in men aged 15-35 and is thus a diagnosis that negatively impacts many men early in their lives. Testicular cancer is also quite common in dogs but comes with several differences compared to the human counterpart. While testicular cancer typically occurs in young men, it is commonly found in older dogs. An additional difference is the cell type of origin – in men, the vast majority of testicular cancers are germ cell-derived, while in dogs most originate from epithelial Sertoli cells or interstitial Leydig cells. The exact cell type of origin can be difficult to define, as tumors often have a mixture of involved cell types. Also, the etiology of testicular cancers is poorly understood, and there are few molecular markers available for the clear diagnosis of specific tumor type for both humans and dogs. Although the prognosis for men (and dogs) diagnosed with testicular cancer is relatively good following surgical removal of the affected testis, the decision to follow up with radiation or chemotherapy is a difficult one to make based on our limited understanding of testicular cancer development and progression. Here, we present an analysis of human and canine case studies that examines distinct histological and protein marker expression changes in normal and abnormal (tumor-containing) testes. Results will be compared to published reports in the literature and data of previously conducted studies, with the goal to provide clearer diagnostic and prognostic tools for testicular cancers in both humans and dogs.