Nodular fasciitis

Nodular fasciitis
Micrograph of nodular fasciitis showing the haphazard arrangement of cells (tissue culture-like pattern). H&E stain.
Classification and external resources
Specialty	rheumatology
ICD-10	M72.4
ICD-9-CM	728.79

Nodular fasciitis, also known as nodular pseudosarcomatous fasciits,^[1] pseudosarcomatous fasciitis,^[2] and subcutaneous pseudosarcomatous fibromatosis,^[1]:992 is a benign^[3] soft tissue lesion most commonly found in the superficial fascia. The lesion commonly occurs in the first three decades of life. Upper extremities and trunk are the most common affected anatomical sites. Previous history of trauma may be present. Clinically and histologically, nodular fasciitis may be mistaken for a sarcoma.

Etiology and clinical course

Until recently, nodular fasciitis have been considered a reactive process of uncertain etiology.^[4] However, recent findings indicate that nodular fasciitis is a self-limited clonal neoplastic process (see below). Clinically, nodular fasciitis presents as a subcutaneous "growth" over a period of 3–6 weeks that eventually regresses. The lesion usually reaches a size of 2–3 cm. Larger lesions are unusual. Local recurrence has been described after simple surgical excision but it is rare.

Histology

• Histologically vast array of patterns.
• Short S-shaped fascicles, inflammation, accelerated mitotic index with normal mitoses.
• Essentially spindle cell proliferation.
• Stroma is rich in collagen and/or myxoid ground substance.

Additional images

• 
  Low mag.
• 
  Intermed. mag.
• 
  Goldner, 400x

See also

• Leiomyosarcoma
• List of cutaneous conditions
• Inflammatory myofibroblastic tumour

References