Nodular fasciitis and related pseudosarcomatous lesions of soft tissues.

BACKGROUND Nodular fasciitis is characterized by a proliferation of spindle cells which may be misdiagnosed as sarcomas due to the rich cellularity, mitotic activity and variant morphologic patterns. METHODS This report includes 42 cases of nodular fasciitis and related conditions of skin and soft tissue from the pathology files of the Royal Brisbane Hospital, Queensland, Australia. There were 33 cases of nodular fasciitis, three cases of ossifying fasciitis, three cases of proliferative fasciitis, two cases of proliferative myositis and one case of intravascular fasciitis. Two-thirds of cases were referred from outside Royal Brisbane Hospital. RESULTS Nodular fasciitis and ossifying occurred most commonly in young adults with 16 patients (44%) between the ages of 20 and 29. However, the other variants of nodular fasciitis including proliferative myositis and intravascular fasciitis occurred in older people (six patients being older than 49 years) and more commonly occurring in men (n=5). A painless rapidly growing mass was most common. The lesions of nodular fasciitis were most often located in the upper extremity with the forearm most commonly affected. CONCLUSIONS Nodular fasciitis and related conditions are benign. All patients are alive and well 3 months to 13 years (mean 7.2 years) after simple local resection.