Home > G. Tumoral pathology > primitive myxoid mesenchymal tumor of infancy

primitive myxoid mesenchymal tumor of infancy

Tuesday 4 April 2006

Synopsis

- infants or neonates (50%)
- localization: trunk, extremities, and head and neck
- nonencapsulated tumors
- multinodular appearance
- focal infiltrative growth
- white fleshy cut surface
- tumor diameter ranging from 2 to 15 cm
- diffuse growth
- primitive spindle cells or polygonal cells or round cells
- myxoid background
- vaguely nodular pattern
- peripheral collagenized stroma
- higher cellularity at the periphery
- delicate vascular network in the background

Immunohistochemistry

- diffuse reactivity for vimentin
- no reactivity for smooth muscle actin, muscle specific actin, desmin, S-100 protein, or myogenin

Electron microscopy

- poorly differentiated fibroblastic proliferation

Cytogenetics

- Chr.Y rearrangements
- Chr.9 rearrangements
- Chr.3 rearrangements

Differential diagnosis

- soft tissue sarcomas

  • embryonal rhabdomyosarcoma
  • Ewing sarcoma/primitive neuroectodermal tumor
  • congenital infantile fibrosarcoma
  • primitive sarcomas

Complications

- possible recurrences
- possible metastasis

References

- Alaggio R, Ninfo V, Rosolen A, Coffin CM. Primitive myxoid mesenchymal tumor of infancy: a clinicopathologic report of 6 cases. Am J Surg Pathol. 2006 Mar;30(3):388-94. PMID: 16538060

Portfolio

  • Primitive myxoid mesenchymal tumor of infancy (PMMTI)
  • Primitive myxoid mesenchymal tumor of infancy (PMMTI)
  • Primitive myxoid mesenchymal tumor of infancy (PMMTI)
  • Primitive myxoid mesenchymal tumor of infancy (PMMTI)