A 50-year-old man is referred for evaluation of a lump on his left forearm. The condition was first noted 3 months ago and is asymptomatic. He describes the initial presentation as “pea-sized” in length. The patient’s medical history is unremarkable except for a >30-year history of cigarette smoking. Examination reveals a firm, 2.5-cm, well-defined nodule. No similar lesions are noted elsewhere.
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Nodular fasciitis is a self-limited myofibroblastic neoplasm that affects subcutaneous tissue as well as muscle and fascia. The condition was first described in 1955 and was originally classified as a pseudosarcoma because of its resemblance to sarcoma but with a benign outcome.1 The term nodular fasciitis was first proposed in 1966.2
The tumors most frequently present as well-circumscribed lesions on the upper extremities and trunk of young to middle-aged adults.3 Up to 10% of cases are associated with antecedent trauma.4 Lesions are painless but are characterized by rapid growth. Histologic examination reveals spindle cells within a myxoid stroma. Mitotic figures are prominent. Immunohistochemistry is recommended to differentiate nodular fasciitis from sarcoma. Rearrangement of a specific protease gene defines this disorder as a clonal neoplastic proliferation.5 Surgical excision is curative and considered the treatment of choice. Some cases have resolved following intralesional steroid injections.6
Lauren Ax, MSPAS, PA-C, is a dermatology physician assistant at the DermDox Center for Dermatology. Stephen Schleicher, MD, is director of the DermDox Center for Dermatology, associate professor of medicine at Commonwealth Medical College, and clinical instructor of dermatology at Arcadia University and Kings College.
- Konwaler BE, Keasbey L, Kaplan L. Subcutaneous pseudosarcomatous fibromatosis (fasciitis). Am J Clin Pathol. 1955;25(3):241-252.
- Mehregan AH. Nodular fasciitis. Arch Dermatol. 1966;93(2):204-210.
- de Feraudy S, Fletcher CD. Intradermal nodular fasciitis: a rare lesion analyzed in a series of 24 cases. Am J Surg Pathol. 2010;34(9):1377-1381.
- Luna A, Molinari L, Bollea Garlatti LA, et al. Nodular fasciitis, a forgotten entity. Int J Dermatol. 2019;58(2):190-193.
- Shin C, Low I, Ng D, Oei P, Miles C, Symmans P. USP6 gene rearrangement in nodular fasciitis and histological mimics. Histopathology. 2016;69(5):784-791.
- Oh BH, Kim J, Zheng Z, Roh MR, Chung KY. Treatment of nodular fasciitis occurring on the face. Ann Dermatol. 2015;27(6):694-701.