Radiation Oncology/Germ cell

Germ Cell Tumors


  • Germ cells originate in the yolk sac endoderm
  • During embryonal development, they migrate around the hindgut to the urogenital ridge
  • Germ cell tumors arise either after normal migration (in testes or ovaries) or after abnormal migration in midline structures (e.g. CNS, mediastinum, retroperitoneum)
  • Degree of differentiation determines the histologic type
    • Suppressed differentiation: Germinoma (germinoma/seminoma/dysgerminoma)
    • Differentiation: Non-Germinomatous Germ Cell Tumors (NGGCT/NSGCT/Nondysgerminoma)
      • Embryonic differentiation:
        • Embryonal Carcinoma
        • Teratoma: Mature or Immature
      • Extra-embryonic differentiation
        • Choriocarcinoma
        • Yolk Sac Tumor (Endodermal Sinus Tumor)
      • Mixed Germ Cell tumors
  • Germ cell tumors have the same morphologic and histologic appearance regardless of whether they originate in the gonads or in extra-gonadal sites
  • Serum half-life:
    • bHCG: 1-1.5 days
    • AFP: 5-7 days


Official GuidelinesEdit