Nodular fasciitis of the head and neck region: a clinicopathologic description in a series of 30 cases.

Nodular fasciitis (NF) is a reactive lesion composed of fibroblasts/myofibroblasts and most commonly found in extremities and trunk. NF has been described in the head and neck region (HNR) in 13-20% of cases. It is our impression based on consultation experience that many pathologists do not consider NF in the differential diagnosis of soft tissue masses arising in the HNR. Moreover, it is common for these lesions to be incompletely excised, leading to additional challenges in diagnosis. We describe 30 cases of NF of the HNR in order to focus attention on this frequently overlooked diagnosis. While they had the typical histologic features of NF, the lesions had a tendency for smaller size, increased skeletal muscle involvement (30%) compared to fasciitis elsewhere in the body and diffuse and strong actin expression. Follow up demonstrated one recurrence (7.1%) higher than reported elsewhere in the body. These latter features may add to the challenge in diagnosing NF in these locations.