Cervical myelopathy and extensive body destruction caused by primary Gli1 fusion sarcoma

Abstract

Sarcomas of the cervical spine with osteolytic lesions and intradural extension are extremely uncommon. This is a case report of a woman in her late 30s who had experienced numbness and gradual weakness of her four limbs. MRI with enhanced T1‐weighted contrast showed a heterogeneously enhancing intradural extramedullary mass lesion over C2–C4 levels compressing the spinal cord. Over the corresponding levels, the computed tomography scan showed an osteolytic lesion. Surgical intervention was performed under intraoperative neuromonitoring. Histopathological findings demonstrated a low‐grade tumor with round to ovoid nuclei with a moderate amount of eosinophilic cytoplasm with minimal nuclear pleomorphism. Next‐generation sequencing technology was employed and findings revealed PTCH1::GLI1 and GLI1::KDM2B fusion with strongly positive findings on GLI1 immunohistochemical staining. The final diagnosis was GLI1 fusion sarcoma. The patient recovered well under multidisciplinary treatment with stringent follow‐up, which are required for this rare disease entity.