A Rare Mesenchymal Neoplasm in an Uncommon Anatomical SiteSolitary Fibrous Tumour of Vulva

Previously, Solitary Fibrous Tumour (SFT) was thought to originate from the pleura, a relatively rare mesenchymal neoplasm with an indolent course. Vulva is a very uncommon site of extrathoracic SFT. This is a report of a very uncommon case of vulval SFT in a 30-year-old female with complaint of a swelling over vulval region. Fine Needle Aspiration Cytology (FNAC) of the growth was attempted twice and only blood was aspirated. The swelling was excised completely. On histological examination, the sections revealed a cellular tumour of ovoid-to-fusiform spindle cells with indistinct cell borders, with haphazard arrangement or patternless pattern along with proliferation of variable sized blood vessels. The diagnosis was finalised to be a benign stromal tumour (most probably SFT), which was confirmed on immunohistochemical examination using Cluster of Differentiation 34 (CD34), CD99 and Signal Transducer and Activator of Transcription 6 (STAT6) markers.