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)