Purpose: We report a very rare case of a fast-growing benign fibrous histiocytoma at the temporal bone.
Methods: A 1-year-old girl was referred for investigation of a right temporal mass that increased during 2-week observation. Imaging studies showed a lytic, loculated skull tumor at the left temporal bone. On magnetic resonance imaging scans, the tumor was isointense on T1- and relatively high-intense on T2-weighted images. The tumor was mostly homogeneously enhanced by gadolinium. On diffusion-weighted images, it was iso- to relatively low-intense; perfusion-weighted images revealed low perfusion.
Results: Complete macroscopic resection of the tumor was performed. Immunohistochemical analysis showed that the tumor was positive for CD68 and α-smooth muscle actin and negative for CD1a and CD34; the MIB-1 labeling index was 4 %. A diagnosis of primary benign fibrous histiocytoma of the skull was made. At 6-month follow-up, there were no clinical or radiological signs of tumor recurrence and/or metastasis.
Conclusions: We review the clinical, radiological, and immunohistochemical characteristics of benign fibrous histiocytoma at the skull.
Keywords: Benign fibrous histiocytoma; Neurocranium; Skull tumor.