Pure lumbar foraminal cavernous malformation in a patient with Cowden syndrome-a case report.

Background: Spinal cavernous malformations (CMs) are slow flow venous vascular malformations which can occur in vertebral body, epidural space or intramedullary. Only 7 cases were described confined in foraminal space. Cowden syndrome (CS) is an autosomal dominant genodermatosis that may present and develop vascular malformations, which include CM. They were found intracranial, and rarely visceral. No association with spinal CM and CS has been reported to date.

Case Description: A 46-year-old patient with CS came to our attention with a L5 radiculopathy secondary to a slow-growing intra-foraminal mass lesion, with bony scalloping. The lesion mimicked a schwannoma at radiological imaging and intraoperative findings. En bloc resection with root sacrifice was performed. No excessive bleeding was observed. After surgical resection, anatomical pathology demonstrated a CM. Postoperative review of neuroimaging revealed features compatible with chronic resolved peripheral haemorrage. The patient had no intra- or post-operative complications, and an immediate relief of symptoms was observed. The follow-up spinal magnetic resonance imaging (MRI) obtained 3 months after surgery, demonstrated the total removal of the lesion.

Conclusions: CMs can be confined to foraminal space and associated with CS. They may mimic peripheral nerve sheath tumors. Diagnosis may be challenging. No pathognomonic imaging features were found. Complete resection with root sacrifice seems to be a safe and efficient technique.