Testicular germ cell tumor (TGCT) is the most common malignancy in men aged 18-45 and accounts for the most life-years lost of any non-pediatric cancer. Over 80% of TGCTs will be cured through a combination of chemotherapy and surgery, but treatment-related adverse events are common and devastating to the typically young men that present with TGCT. These side effects include deafness, heart disease, infertility, second malignancies, and more. Our research is focused on finding strategies to minimize these adverse events by (1) identifying low-risk patients that would benefit from minimal treatment or surveillance, and (2) devising methods of sensitization to current therapies.