April 6, 2017
A 13-month-old girl with an enlarging right forehead mass, initially noticed after minor trauma 7 months ago; lesion is solid with no bruit, skin changes, or associated inflammatory signs
Cranial Fasciitis of Childhood
- Background:
- Cranial fasciitis is a rare, benign fibromuscular tumor of the skull found predominantly in children under the age of 6. Histologically, its appearance is identical to nodular fasciitis.
- Clinical Presentation:
- Presents as a rapidly growing, palpable, nonmobile and nontender scalp mass
- Symptoms are usually related to mass effect on adjacent structures.
- As in this case, head trauma is a possible inciting factor.
- Key Diagnostic Features:
- Mass arising from the deep fascia of the scalp, with erosion of the outer table of the calvarium; Some may progress with erosion through the inner table of the calvarium extending to the dura.
- Radiographs and CT will demonstrate a single lytic skull lesion with either nonaggressive-appearing thin osseous rim or aggressive-appearing periosteal bone formation, and an associated heterogeneous enhancing soft tissue mass which may contain internal calcification.
- MRI will demonstrate a heterogeneous mass isointense to gray matter on T1 and T2, with homogeneous postcontrast enhancement, no restricted diffusion, and some may have associated dural thickening and enhancement; there are no flow voids or signs of intratumoral AV shunt.
- Differential Diagnoses:
- Langerhans cell histiocytosis: well-defined lytic skull lesion with beveled margin; inner table calvarium more often involved than outer table; can have multiple lesions
- Calvarial hemangioma: intact calvarium; vascular flow voids; T2 markedly hyperintense
- Cephalohematoma: not vascular; little or no enhancement
- Metastasis: history of cancer; older patients
- Epidermoid cyst: well circumscribed; T2 hyperintense; does not enhance; marked DWI restriction
- Treatment:
- Definitive curative therapy is surgical excision. Some may involute on their own after partial excision.
