Epidemiology of testicular cancer.

Testicular cancer is of interest and importance because its incidence has been increasing in most countries over the past four decades. Although it remains an uncommon malignancy overall accounting for 1-2% of all tumours in men, testicular cancer is the most common malignancy in young men. There is marked geographical variation in the incidence of testicular cancer, with the highest incidence among men in Nordic countries and lowest incidence among men in the Middle East and Asia. The association between some risk factors, including cryptorchidism, a previous history of testicular cancer and a family history of testicular cancer, and the incidence of testicular cancer has been widely reported. We reviewed published reports and present the evidence to support or refute the association between the well-established and the less well-established risk factors and the incidence of testicular cancer.