Hamartoma

Clinical features

  • Benign tumour/tumour like malformation
  • Rare in children
  • Association with other malformations and tumours
  • X-ray-
    • Peripheral coin lesion with well demarcated borders
    • Calcification (curvilinear popcorn)-diagnostic-best seen in computed tomography

 

Fig 88 – Lung Hamartoma Smear from a transthoracic guided fine needle aspiration, Fragment of mesenchyma in a myxoid matrix. (H&E)
Fig 89 – Lung Hamartoma- Smear from a transthoracic guided fine needle aspiration, Fragment of malformed cartilaginous tissue and few aggregates of epithelial cells (H&E)
Fig 90 - Hamartoma – Smear from a transthoracic guided fine needle aspiration; numerous epithelial cells together with immature cartilage (H&E)

 

  • Malformed cartilage -the presence of cartilage by itself is not enough
  • Mesenchymal myxoid matrix (essential to diagnose) (characteristic linear fibrillary parallelism)
  • Sheets of bronquial epithelium

 

Immunocytochemistry

No contributory

 

Modern Techniques of Diagnosis

No contributory

 

Differential Diagnosis

  • Normal tissue from chest wall or bronchus
  • Teratoma (Dermoid)
    • More frequent in the mediastinum
    • Cartilage can also be seen as well as mesenchymal tissue
  • Blastoma
    • Cartilage is immature
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