An intracranial mass is removed from a 33-year-old patient. Th | Uworld | Step 1

An intracranial mass is removed from a 33-year-old patient. The mass is composed of cells that have elongated, wavy nuclei. A biphasic pattern of growth is identified, consisting of areas of dense cellularity interspersed with less dense myxoid regions. The cells show diffuse S-100 immunoreactivity.