Screening is advised in individuals who are deemed at high risk of testis tumours, e.g. affected first degree relative (especially an identical twin), history of a delayed or undescended testis, and particularly patients who have had a prior malignancy in the contralateral testicle. These individuals should perform monthly testicular self-examination. In addition, patients with a previous malignancy of the opposite testis should be examined by clinicians at regular intervals.