Yolk sac tumour

Clinical features

  • Children and young adults
  • Serum elevation of alpha-fetoprotein
  • Frequently develops from a teratoma
  • More common in the ovary than in the testis
  • Rare locations: retroperitoneum and mediastinum
  • No association with endocrine symptoms
  • Malignant-5-year survival-66.6%

 

Fig 69- Yolk sac tumor - Papillary aggregates of pleomorphic tumor cells (H&E)
Fig 70 - Yolk sac tumor – Cells are large and polygonal with hyperchromatic nuclei. Eosinophilic hyaline globules in extracellular location (H&E)
Fig 71 - Yolk sac tumor –Pleomorphic nuclei with coarse chromatin and eosinophilic nucleoli. Cytoplasm is pale and fragile (H&E)
Fig 72- Yolk sac tumor –Groups of neoplastic cells and dense basement membrane-like matrix (Giemsa)

 

 

  • (Macroscopically aspirates can carry translucent and viscous material
  • Moderate to high cellularity
  • Cells embedded within the matrix
  • Single cells or in spherical or papillary aggregates
  • Large polygonal cells
  • Hyperchromatic nuclei
  • Frequent nucleoli
  • Pale cytoplasm with vacuoles of glycogen
  • Mucoid background
  • Dense basement membrane-like matrix
  • Eosinophilic hyaline globules in intra or extracellular location  
  • Necrosis

 

Immunocytochemistry (see Table 1)

  • Alpha-fetoprotein: positive
  • Alpha-1-antitrypsin: positive (focal)
  • CEA: positive
  • Cytokeratin: positive
  • PLAP: positive
  • Human chorionic gonadotropin: negative
  • Vimentin: negative
  • CD30: negative

 

Histochemical stains

  • Eosinophilic hyaline globules (PAS-diastase positive)

 

Differential diagnosis

  • Embryonal carcinoma
    • Rare presence of hyaline globules
    • Absence of dense basement membrane-like matrix
    • Alpha-fetoprotein: generally negative
    • PLAP: positive
    • CD30: positive       
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