Demographics

• Men 15-45
• Incidence highest in western/northern europe
• Mortality highest in asia

Aetiology

Environmental factors

• Cryptorchidism (undecended testis)
• Fam Hx
• Infection
• Testicular trauma
• Hx of testicular cancer

Genetic factors (no single gene found yet)

Pathophysiology

Germ Cells Carcinomas 95%:

• Seminoma (most common)
• Non Seminoma (NSGCT) - dissemination/metastasis via lymph.
  • Embryonal Cancer (haemorrhagic)
  • Teratoma
  • Chriocarcinoma
  • Yolk sac tumour (haemorrhagic)

Poorly understood patho. Both arise from a precursor lesion, germ cell neoplasia in situ (GCNIS), which develops from arrested spermatocytes that failed to differentiate (? Maternal RFs - controversial)

Sex cord/stroma tumours 5%