Pediatric Mesenchymal Hamartoma

  • Etiology: Benign liver neoplasm
  • Imaging:
    — Typically cystic (80%) but can have variable solid component
    — Does not have hemorrhage or calcifications or enhancement
  • DDX:
  • Complications: Dedifferentiation to undifferentiated embryonal sarcoma of the liver
  • Treatment: Surgical resection due to mass effect and malignant potential
  • Clinical:
    — Usually in less than 1 year old
    — Does not cause elevation of AFP

Radiology Cases of Mesenchymal Hamartoma

MRI of mesenchymal hamartoma
Axial T1 weighted without contrast (above) and T2 weighted (below) MRI of the abdomen shows a mass in the right lobe as well as in the medial segment of the left lobe of the liver, measuring 13 x 13 x 7 cm in size and having a cystic and solid appearance.
US of mesenchymal hamartoma
Transverse and sagittal US images of the liver shows a large complex septated liver mass.

Surgery Cases of Mesenchymal Hamartoma

Surgical image of mesenchymal hamartoma
Surgical image shows a massive tumor in the left medial segment of the liver after it has been delivered. The left lateral segment of the liver and the right lobe of the liver appeared normal and this was confirmed by intraoperative ultrasound. The patient underwent a left medial segment hepatectomy.
Surgical image of mesenchymal hamartoma
Surgical image of the under surface of the liver with the hila being dissected shows a large tumor in the left medial segment of the liver.

Histopathology Cases of Mesenchymal Hamartoma

Histopathology image of mesenchymal hamartoma
Histopathological image H&E stained section showing fibrous tissue containing disorganized vessels. Frequently, the stroma in these lesions is more myxomatous and bile ducts or cysts lined by biliary-type epithelium are more numerous. Islands of hepatocytes are present at the corners of the image.
Histopathology image of mesenchymal hamartoma
Histopathological image of additional H&E stained section.
Histopathology image of mesenchymal hamartoma
Histopathological image of additional H&E stained section.