Review of Pediatric Extraosseous Chordomas with a Unique, Illustrative Case.

Introduction: Chordoma is a rare, aggressive tumor that is believed to originate from notochord remnants. It can occur anywhere from the clivus to the sacrum and often recurs even after resection and radiotherapy. We present a unique case that initially suggested a different pathology based on imaging and presentation but was found to be a chordoma on gross and pathological analysis.

Case presentation: An 11-year-old girl presented outpatient for scoliosis evaluation and was found to have what appeared to be a right L4 peripheral nerve sheath tumor on MRI, causing dextroconvex scoliosis. She underwent a gross total resection via a retroperitoneal approach and was found to have what appeared to be an extraosseous, extradural, extra-spinal canal lumbar chordoma. Immunohistochemical features on surgical pathology were consistent with chordoma. The patient was referred to radiation oncology for adjuvant radiotherapy and pediatric hematology/oncology for recurrence monitoring.

Discussion: Our case is the first to present in such a manner, was shown to be external to the spinal canal, encasing the nerve root, and was the first such case in a pediatric patient. We reviewed the growing body of literature on spinal extraosseous chordomas and their characteristics within the pediatric patient population. We also reviewed chordoma pathogenesis theories as well as current and future treatment options.