Primary Intracranial Ewing's Sarcoma (Peripheral Primitive Neuroectodermal Tumour of Parietal Bone) with Spinal and Pelvic Metastasis in a Young Female Child: Rare Case Report and Review

Abstract

Introduction The Peripheral Primitive Neuroectodermal Tumour (pPNET)/Ewing's sarcoma family tumor (ESFT) group is a recently redefined term which includes all small round cell tumors of bone, soft tissue, and nerve with a common neuroectodermal origin. These highly aggressive pediatric soft tissue tumors occur less frequently in the craniospinal axis. Primary cranial lesion associated with spinal and pelvic metastasis is a rare presentation. Clinical Presentation A 9-year old girl was hospitalized with features of progressive increase in intracranial pressure with quadriparesis. The patient had ⅘ quadriparesis with bilateral papilledema. Brain MRI showed a large, hetero intense, contrast enhancing right parietal bony lesion infiltrating the dura with mass effect over the brain. Brain CT showed bony expansion and multiple calvarial lytic lesions. MRI cervical spine revealed collapsed fourth cervical vertebral body with extensive paravertebral and paraspinal soft tissue components with cord compression. Metastatic workup revealed a lytic lesion in the left iliac bone and left lung. The patient underwent a surgically challenging C4 corpectomy with cage fixation followed by craniotomy and excision of parietal bony lesion with titanium mesh cranioplasty in the same sitting. Histopathology revealed pPNET and was confirmed by CD99 positivity. Conclusion This rare multiple site tumor presentation was carefully planned and effectively managed by a combined single-stage surgical approach involving total excision of primary parietal bone and metastatic cervical spine tumors with primary