Figure 1
Ultrasonography of the neck
shows an ovoid mass in the lower part of the left sternocleido-mastoid muscle (<i>arrows</i>).
Clinical History
Torticollis and mass in the left neck region which was discovered two weeks after birth. Delivery was uncomplicated at a gestational age of forty weeks. The child was in good general condition without increased inflammatory parameters.
Imaging Findings
The patient presented with torticollis and a mass in the left neck region which was discovered two weeks after birth. Delivery was uncomplicated at a gestational age of forty weeks. The child was in good general condition without increased inflammatory parameters.
Ultrasonography of the neck shows an ovoid mass in the lower part of the left sternocleido-mastoid muscle (arrows).
MRI of the neck demonstrates on the coronal SE T1-weighted image (fig. 2 A) the presence of a fusiform enlargement of the left sternocleidomastoid muscle isotense to surrounding normal muscle (arrows).
On the axial SE T2-weighted image the lesion is almost homogeneous and predominantly of high signal intensity (arrows).
Ultrasonography of the neck ten months later shows almost complete regression of the swelling (arrows).
The clinical history, age of the patient, localization and the imaging findings suggest the diagnosis of fibromatosis colli.
Ultrasonography of the neck shows an ovoid mass in the lower part of the left sternocleido-mastoid muscle (arrows).
MRI of the neck demonstrates on the coronal SE T1-weighted image (fig. 2 A) the presence of a fusiform enlargement of the left sternocleidomastoid muscle isotense to surrounding normal muscle (arrows).
On the axial SE T2-weighted image the lesion is almost homogeneous and predominantly of high signal intensity (arrows).
Ultrasonography of the neck ten months later shows almost complete regression of the swelling (arrows).
The clinical history, age of the patient, localization and the imaging findings suggest the diagnosis of fibromatosis colli.
Discussion
Fibromatosis colli is a congenital fibrous tumor, mostly located in the sternal head of the sternocleidomastoid muscle. Typical clinical presentation consists of a painless, firm nodular swelling in the neck with largest diameter of one to three centimeters.
Mostly, the lesion is discovered two to five weeks after birth and enlarges gradually until the age of three to six months. Spontaneous regression and disappearance between the age of six to twelve months is common. When the lesion persists after one year, surgery should be considered.
Recognition of this entity can avoid unnecessary diagnostic and therapeutic maneuvers. On ultra-sonography, the mass is spindle – shaped and usually uniformly hypoechoic to its surrounding. The swelling is isodense to normal muscle on CT scan. T1-weighted MR-images show a signal intensity equal to normal muscle and a less homogeneous lesion of intermediate signal intensity on T2-weighted images. Among the multiple theories that explain the etiology of the lesion, the ischemic theory is most widely accepted and supported by several studies. This theory states that the fibromatosis develops following temporary venous obstruction in the muscle, which should be rendered permanent by patchy intravascular clotting in the obstructed venous tree.
On cytopathology there is low cellularity and admixture of myofibers and spindle shaped cells. The mixture of fibroblasts and residual degenerating skeletal muscle is stated to be diagnostic of fibromatosis colli.
Differential diagnosis includes cervical lymphadenopathy, lymphadenitis, cervical teratoma, branchial cleft remnant, congenital goiter, heterotopic thyroid, lymphangioma, hemangioma, accessory lobe of thymus, and sarcoma.
Mostly, the lesion is discovered two to five weeks after birth and enlarges gradually until the age of three to six months. Spontaneous regression and disappearance between the age of six to twelve months is common. When the lesion persists after one year, surgery should be considered.
Recognition of this entity can avoid unnecessary diagnostic and therapeutic maneuvers. On ultra-sonography, the mass is spindle – shaped and usually uniformly hypoechoic to its surrounding. The swelling is isodense to normal muscle on CT scan. T1-weighted MR-images show a signal intensity equal to normal muscle and a less homogeneous lesion of intermediate signal intensity on T2-weighted images. Among the multiple theories that explain the etiology of the lesion, the ischemic theory is most widely accepted and supported by several studies. This theory states that the fibromatosis develops following temporary venous obstruction in the muscle, which should be rendered permanent by patchy intravascular clotting in the obstructed venous tree.
On cytopathology there is low cellularity and admixture of myofibers and spindle shaped cells. The mixture of fibroblasts and residual degenerating skeletal muscle is stated to be diagnostic of fibromatosis colli.
Differential diagnosis includes cervical lymphadenopathy, lymphadenitis, cervical teratoma, branchial cleft remnant, congenital goiter, heterotopic thyroid, lymphangioma, hemangioma, accessory lobe of thymus, and sarcoma.
Differential Diagnosis List
Fibromatosis colli of infancy
Final Diagnosis
Fibromatosis colli of infancy
References
[1] Crawford S, Harnsberger H, Johnson L et al. Fibromatosis colli of infancy: CT and sonographic findings. Am J Roentgenol 1988; 1183-1184. (PMID: 3055894)
[2] De Schepper AM, Vandevenne JE. Tumors of fibrous tissue. In: Imaging and soft tissue tumors, ed. De Schepper AM, 1st edn., Springer Verlag Heidelberg, 1996; 147-172.
[3] Wakely PE, Price WG, Frable WJ. Sternocleidomastoid tumor of infancy (fibromatosis colli): diagnosis by aspiration cytology. Modern Pathol 2, 1989; 378-381. (PMID: 2762289)
Case information
| URL: | https://eurorad.org/case/944 |
| DOI: | 10.1594/EURORAD/CASE.944 |
| ISSN: | 1563-4086 |
Figure 2
Coronal SE T1-weighted image
demonstrates on the coronal SE T1-weighted image the presence of a fusiform enlargement of the left sternocleidomastoid muscle isotense to surrounding normal muscle (<i>arrows</i>).
on the axial SE T2-weighted image the lesion is almost homogeneous and predominantly of high signal intensity (<i>arrows</i>).
Figure 3
Ultrasonography of the neck
of the neck ten months later shows almost complete regression of the swelling (<i>arrows</i>). The clinical history, age of the patient, localization and the imaging findings suggest the diagnosis of fibromatosis colli.
Ultrasonography of the neck
shows an ovoid mass in the lower part of the left sternocleido-mastoid muscle (<i>arrows</i>).
Coronal SE T1-weighted image
demonstrates on the coronal SE T1-weighted image the presence of a fusiform enlargement of the left sternocleidomastoid muscle isotense to surrounding normal muscle (<i>arrows</i>).
on the axial SE T2-weighted image the lesion is almost homogeneous and predominantly of high signal intensity (<i>arrows</i>).
Ultrasonography of the neck
of the neck ten months later shows almost complete regression of the swelling (<i>arrows</i>). The clinical history, age of the patient, localization and the imaging findings suggest the diagnosis of fibromatosis colli.