Aetiology

Non-descent or maldescent of the testis is a predisposing factor for testicular tumours, increasing the risk by 30-fold.

The higher the location of the undescended testicle, the greater the risk of malignancy:

• 1 in 20 for an intra-abdominal testicle
• 1 in 100 for an inguinal testicle

This risk is not modified by orchidopexy, suggesting that it may be an underlying abnormality of the testes which predisposes both to malignancy and to maldescent. However, orchidopexy does allow earlier recognition of malignant change.

Other factors implicated:

• genetic - no well defined pattern of inheritance
• testicular dysgenesis - 25% develop malignancy
• maternal factors - increased maternal weight and adiposity influencing the endocrine environment of the developing foetus and initiating changes which predispose to later malignancy

Reference:

• (1) Cancer Research UK. Testicular cancer incidence statistics
• (2) Office for National Statistics 2013. Testicular cancer incidence rates have more than doubled in the last 40 years
• (3) Horwich A et al. Testicular germ cell tumour. BMJ. 2013;347:f6205