summary Nodular Fasciitis is a common, fibrous, soft tissue lesion that usually occurs in the upper extremities of young people. Diagnosis is made with MRI studies showing a deep-seated inhomogeneous mass with nodularity along the fascial planes. Biopsy shows short irregular bundles and fascicles in a dense reticulum network. Treatment is usually marginal surgical resection. Epidemiology Incidence most common fibrous soft tissue lesion half of the cases occur in the upper extremities Demographics males and females equally affected Anatomic location volar forearm, back, chest wall, head and neck Presentation Symptoms may be painless or painful painful in half of patients often rapidly enlarging mass over 1 to 2 weeks lesions 1 to 2 cm Imaging Radiograph usually normal MRI shows deep seated inhomogeneous mass nodularity with extension along the fascial planes avid enhancement with gadolinium most commonly is superficial but can occur intramuscularly or along the superficial plane Histology Classic characteristics are short irregular bundles and fascicles dense reticulum network small amounts of mature collagen Treatment Operative marginal resection Differential Differential of Nodular Fasciitis Treated with marginal excision Nodular fasciitis (soft tissue) o Periosteal chondroma o Neurilemoma (soft tissue) o Epidermal inclusion cyst o Glomus tumor o