Fig 5a,b . Large vascular tumor of size 8.0x6.5cm in left parapharyngeal space infiltrating into deep lobe of parotid laterally, reaching pterygoid plate medially extending up to skull base superiorly and up to angle of mandible inferiorly
Histopathology of excised specimen revealed a well circumscribed tumor composed of haphazardly arranged spindle shaped cells with attenuated nuclei in a collagenized background with hyper and hypo cellular areas were seen. The stroma showed presence of hemangiopericytomatous pattern of blood vessels. Mitosis was <3/hpf. On IHC, the cells were positive for CD34, negative for SMA, Chromogranin, synaptophysin, CD31, Vimentin and Ki index-2%. Therefore, it was diagnosed as Solitary fibrous tumor. (Fig 6a, 6b)