Aspiration cytology of elastofibroma dorsi: case report with ultrastructural and immunohistochemical findings.

Elastofibroma is a well-recognized tumor-like process which typically occurs in the soft tissue of the shoulder. Although fine-needle aspiration (FNA) represents a quick and simple method for definitive diagnosis, the possibility of a false-negative diagnosis is high due to the hypocellularity of the smears. However, a high index of suspicion based on the clinical presentation of a firm mass in a typical location in an elderly person, usually female, aids in the diagnosis. We describe the FNA findings of elastofibroma dorsi in an 89-yr-old woman which, although hypocellular, contained diagnostic aggregates of petaloid globules within a collagenous matrix. The cytologic material showed a green-yellow autofluorescence of the altered elastic fibers with ultraviolet light. Transmission electron microscopy revealed an elongated beaded appearance with small electron densities and obliteration of the central elastin core. The presence of a hypocellular aspirate with autofluorescent elastic fibers should suggest the possibility of elastofibroma dorsi.