Sections show a benign meningeal neoplasm characterized by a transitional architectural pattern. The tumor is composed of proliferating meningothelial cells arranged in prominent syncytial sheets and conspicuous, well-formed concentric cellular whorls. The tumor cells exhibit abundant, pale eosinophilic cytoplasm with ill-defined cell borders and uniform, bland oval nuclei containing delicate, finely dispersed chromatin; focal intranuclear pseudoinclusions are noted. Interspersed within the cellular whorls and stroma are scattered to frequent laminated, calcified psammoma bodies. There is no evidence of hypercellularity, small cell change, spontaneous necrosis, or increased mitotic activity. No features of atypia or malignancy are identified.
Anterior fontanelle soft tissue mass.
Soft tissue fragments collectively measured 6.5x5.5x2.5 cm, the largest measuring 3.5x3x2.5 cm.
Anterior fontanelle mass, excision: