Testicular conditions
Testicular microlithiasis and cryptorchidism have both been associated with increased risk of testicular cancer, which is in line with the highly suggestive evidence stemming from the present study. The majority of preadolescent boys with testicular microlithiasis and cancer have other predisposing conditions, such as cryptorchidism. Testicular microlithiasis is a relatively uncommon condition characterized by the presence of calcifications in the testicular parenchyma, possibly due to dysgenesis of the testis with slough of degenerated cells inside an obstructed seminiferous tubule. The mechanisms that may explain how these calcifications may be involved in the pathogenesis of testicular cancer remain unclear; in particular, it is far less known whether and when a patient with microlithiasis would develop testicular cancer. It is also possible that testicular microlithiasis may be associated with rather than being a risk for future development of testicular tumor, because the follow-up of patients with incidental microlithiasis have shown a low risk of developing testicular cancer. Despite this debate, our results are in line with previous studies supporting the general recommendations of regular screening for testicular cancer in case of testicular microlithiasis. Although the association between cryptorchidism and testicular cancer has been well-studied, the underlying mechanisms remain poorly understood. Cryptorchidism is one of the strongest risk factors for infertility and testicular germ cell tumors. Although corrective surgery largely reduces the risk of this tumor, in some cases the affected testis becomes cancerous. This finding is suggestive of permanent epigenetic changes as differences in promoter methylations and corresponding gene expression of several genes have been reported in testicular germ cell tumors. Gene expression in cryptorchid testes and animal models has shown deregulation of growth factors important for the balance of self-renewal and the proliferation of germ cells . The open question is whether the risk of malignant malformation is the result of a genetic predisposition or is due to the maldescent testis, which is more prone to dysplasia and malformation. In cases of isolated cryptorchidism, the 10% increased risk of developing cancer in the contralateral normally descended testis has provided indications that genetic factors may also play significant role by inducing aberrant gonadocyte development in fetal life.