Temporal Malignant Solitary Fibrous Tumor.

Copyright © Address correspondenc M.D., Ph.D., Department Temple University Schoo Boyer Pavilion, Philadelp E-mail: pamela.roehm@t The authors disclose n man presented with nontender sweleffects, with a slow onset because of A 63-year-old wo ling anterior to her right ear of 1-month duration. She denied hearing loss and dizziness. A palpable defect was detected in the outer table of the calvarium around the mass. Preoperative imaging demonstrated a 3.8 1.8 6.1 cm enhancing mass of the right pterional calvarium and temporal fossa with central T2 hyperintensity accompanied by midline shift but no invasion of the brain (Fig. 1, A–C). There was erosion of the right temporal calvarium, thinning of the tegmen, and a small focal dehiscence in the roof of the condylar fossa (Fig. 1A). After preoperative embolization (Fig. 1D), the patient underwent resection of the mass and cranioplasty. The tumor had eroded through the calvarium and floor of the middle fossa into the mastoid and epitympanum. On frozen section, the presence of spindle cells was noted. Final pathology demonstrated a spindle cell tumor with a vague storiform pattern, mild-to-moderate nuclear atypia, and focal fibrous bands (Fig. 2). There was significant mitotic activity (4–12/10 HPF) (Fig. 2A) and focal necrosis. There was a storiform cellular pattern and focal fibrous bands. The neoplastic cells were strongly immunoreactive to STAT-6 and vimentin (Fig. 2B); focally positive for CD34, BCL2, and cytokeratins (AE1/AE3, Cam 5.2); and negative for S-100, melan –a, EMA, CD31, calponin chromgranin, desmin, smooth muscle actin, p63, CD 21, CD 35, and TLE. FISH for EWSR1 and SYT breakapart analysis were also negative. The immunomorphologic features of the tumor were diagnostic for malignant solitary fibrous tumor (SFT).