SPINAL TUMORS-04 SOLITARY FIBROUS TUMOUR, A DIAGNOSTIC CONUNDRUM (A CASE REPORT)

A 33-year-old male presented with neck pain and early signs of cervical myelopathy. He had a circumferential enhancing C4 tumour with bone demineralization. He had previously had an ACDF and a biopsy of the affected region with variable histology results. Imaging revealed a circumferential C4 tumour with bilateral vertebral encasement and cord compression. He had an extensive tumour debulking , corpectomy and posterior fusion. His neck pain resolved and myelopathy is stable at Nurick grade I. Histology Sections showed cellular tumor composed of spindle cells with little intervening stroma CD34 positive, progesterone receptor negative and EMA. STAT6 was positive confirming a solitary fibrous tumour. Patient has commenced adjuvant radiotherapy. Solitary tumours, formerly classified hemangiopericytoma are rare. In this case, the patient had had three previous inconclusive histological evaluations. Utilization of immunohistochemistry tests enabled the establishment of a conclusive diagnosis and treatment planning. Previously solitary fibrous tumors were classified as hemangiopericytomas with the option of three grades. However, in the current 2021 WHO 5th edition, the term hemangiopericytomas has been dropped to align these tumors fully with the soft tissue pathology nomenclature. These tumors have the characteristic alteration of the NAB2-STAT6 gene/molecular profile.