Imaging spectrum of peripheral primitive neuroectodermal tumours

Primitive neuroectodermal tumours (PNETs) arise from pluripotent neural crest cells and are classified as either central or peripheral. Peripheral PNETs (pPNETs) arise outside the central nervous system and sympathetic chain. These rare neoplasms comprise only 1% of all sarcomas and have highly aggressive biological behaviour and dismal prognosis. Adolescents and young adults are typically affected. Only isolated case reports on pPNETs appearing in both typical and atypical sites can be found in the literature. Timely diagnosis of pPNETs is a challenge to clinicians and radiologists due to the disease's insidious onset and variable locations, coupled with the limited studies that focus on the imaging features of pPNETs. Hence, this article serves to review the imaging features of this rare tumour.