Intradural spinal hibernoma: case report

Hibernoma is a rare, benign tumor arising from vestigial remnants of brown adipose tissue. It usually affects muscle and subcutaneous tissue and is asymptomatic and slow growing.

A review of the worldwide literature contains about 110 cases of hibernomas. However, only two cases (including our case) of hibernoma located in the intradural spine have been reported. We present an extremely rare case of intradural extramedullary spinal hibernoma and summarize the magnetic resonance imaging (MRI) findings of the lesion.

A 35-year-old woman suffered from motor weakness and numbness of the left upper extremity. Cervical spinal MRI revealed an intradural extramedullary mass at C7. She underwent surgery via the posterior approach and the lesion was completely removed. Histopathologic examination showed multivacuolated cells with centrally placed nuclei, and the diagnosis of hibernoma was made.

Because the CT and MRI findings of hibernoma are almost same as those of other lipomatous tumors, a surgical specimen of this tumor is necessary to establish the correct diagnosis. Early diagnosis and total resection are necessary as some cases showed malignant features or rapid growth. Etiologically, the tumor may have developed by the ectopic growth or migration of adipose tissue.