logo efcs bianco

Fibromatosis colli

Bookmark (0)

No account yet? Register

Clinical features

  • Generally present after birth (0,4% of births), during the second until the eight week of life
  • Males more affected than females
  • Often bilateral
  • Associated with congenital anomalies-14%
  • Associated with birth injury-50%
  • In the lower third of the sternocleidomastoid


Fig 31a – Fibromatosis colli – Single fibroblasts, and regenerating multinucleated muscle fibres (H&E)

  • Scant material
  • Bland spindle fibroblasts, single or in clusters
  • Absence of atypia
  • fibromyxoid matrix
  • Regenerating multinucleated muscle fibbers



  • Vimentin: Positive
  • Smooth muscle actin: Positive


Differential Diagnosis

  • Fibrosarcoma
  •  Embryonal rhabdomyosarcoma


Main points

  • Spontaneous regression in weeks to months
  • Torticollis can be a complication
  • Fine needle diagnosis highly recommended, since excision usually is not required