Nodular (pseudosarcomatous) fasciitis, a nonrecurrent lesion: clinicopathologic study of 134 cases.

Clinicopathologic review of 134 patients originally diagnosed as having nodular (pseudosarcomatous) fasciitis is presented. In 114 patients with 116 lesions, no recurrence of the lesion was noted. Of the 114 patients, 85% were younger than 50 years of age, and the forearm and arm were the most common sites of presentation. Nonrecurrent lesions rarely exceed 4 cm and 71% were smaller than 2 cm. In at least six instances, incompletely resected lesions never recurred. Though all lesions were histologically reminiscent of reparative mesenchymal tissue, four subtypes--the reactive type, the densely cellular type, those with osteoid or cartilaginous metaplasia, and the so-called proliferative fasciitis--were distinguished from the majority of lesions that conform to the description given by Kornwaler. Recurrence of the tumor was noted in 18 patients. Fifteen of 18 lesions recurred within two years, and two more recurred at 30 months following initial excision. In all these cases, review of the histology and clinical course led to a revision of the original diagnosis. The greatest number of errors was made in incorrectly classifying of inflammatory fibrous histiocytoma. Recurrence of a lesion originally diagnosed as nodular fasciitis should lead to a careful reappraisal of the pathologic findings.