A novel case of paravertebral glomangiomyomatosis.

Glomangiomyomatosis is an extremely rare variant of glomus tumours. We describe the first known case of paravertebral glomangiomyomatosis in the literature to cause spinal cord compression. A 45-year old female patient presented with sudden onset of left leg pain and progressive weakness in left-sided hip flexion. An MRI spine revealed a large, lobulated, heterogeneous mass cantered on the left L2/3 foramen, mimicking a dumbbell nerve sheath tumour. The mass was invading the psoas muscle and displayed evidence of recent haemorrhage. The patient underwent debulking of the lesion via a left retroperitoneal approach. Surgery was uneventful, with clinical improvement and resolution of leg pain post-operatively. Histopathology of the tumour revealed delineated glomus-like cells and foci of spindled shaped cells resembling myoid differentiation. Immuno-histochemical features of the tumour confirmed the diagnosis of glomangiomyomatosis. The patient continued under close follow up, representing 18 months later with clinical and radiological progression of the disease with similar symptoms of leg pain but no weakness. Follow up MRI revealed progression of the intraspinal and paraspinal components of the tumour with thecal compression. A posterior approach was utilized in order to decompress the intraspinal component, which again was uneventful, and improved the patient's symptoms. This is the first known case of paravertebral glomangiomyomatosis in the literature and this rare entity should be considered in the differential diagnosis of nerve sheath tumours due to risk of progression and recurrence.