Malignant germ cell tumours arise in sperm- or egg-forming cells and usually occur in the reproductive organs, the testes or ovaries. The cancerous tumours are seen in patients of all ages, both in childhood and adulthood. Although many patients do well after treatment, current chemotherapy treatments can have severe long-term side effects, including hearing loss and damage to the kidneys, lungs and bone marrow. For some patients, outcomes remain poor and testicular cancer continues to be a leading cause of death in young men…