Sarcopedia

BenignSoft tissue

Benign Triton Tumour

Synonyms: Neuromuscular hamartoma, nerve rhabdomyoma, ectomesenchymal hamartoma

Benign intraneural proliferation composed of mature peripheral nerve and interspersed muscle

Quick Facts

Behaviour

Benign

Category

Soft tissue

Synonyms

  • Neuromuscular hamartoma
  • nerve rhabdomyoma
  • ectomesenchymal hamartoma

Category

Soft tissue

Behaviour

Benign

Gender

M = F

Tissue of Origin

Neural and muscular

Epidemiology

  • Extremely rare
  • Occurs often in the first decade of life

Clinical Features

May present with neuropathy or plexopathy, muscle atrophy, secondary deformities (cavus deformity, limb growth disturbance)

Location

  • Large nerves
  • Nerve plexuses
  • Cranial nerves

Imaging

MRI: fusiform enlargement of affected nerve, isointense to skeletal muscle in T1 and T2 sequences

Pathology

Smooth or striated muscle fibers among Schwannian nerve fibers

Genetics

Point mutations in CTNNB1

Treatment

  • Standard treatment is not clear due to rarity of condition
  • Surgical resection for symptomatic cases or tumors with mass effect
  • Observation acceptable for for asymptomatic cases
  • Intervention may precipitate the development of desmoid type fibromatosis

Prognosis

  • Local recurrence in 33%
  • 80% develop desmoid type fibromatosis

Key Points

  • Benign intraneural proliferation composed of mature peripheral nerve and interspersed muscle
  • Pathogenesis unclear, no aetiologic associations known

Workup - Blood Tests

No blood tests required

Workup - Local Imaging

MRI with contrast

Follow-up Summary

  1. 1

    Extended follow-up recommended

Medical disclaimer

The content on Sarcopedia is for educational and informational purposes only and does not constitute medical advice. It is not intended to be a substitute for professional medical diagnosis or treatment. Always consult with a qualified physician regarding any health concerns or before starting any new treatment. Reliance on any information provided on this site is solely at your own risk.