Chordoma

Introduction

Chordomas are rare World Health Organization grade I slow-growing neoplasms that are thought to arise from remnants of the notochord. As a result, these tumors can occur anywhere along the spinal axis, in which the majority occur in the sacral region followed by the spheno-occipital or clival region, in which approximately 25% arise in the clivus and account for 0.1% of primary intracranial neoplasms. Chordomas typically involve the spheno-occipital synchondrosis, and those that involve the upper clivus (basisphenoid) can affect the upper cranial nerves, pituitary gland, and hypothalamus, whereas those involving the lower clivus (basiocciput) typically affect the lower cranial nerves. They can also involve the petrous apex, sellar region, sphenoid sinus, nasopharynx, maxilla, and paranasal sinuses, among others. Although these lesions are considered to be low-grade, they are highly invasive, radioresistant, and recurrent. They come in three histologic variants: classical, chondroid, and dedifferentiated. In this chapter, we present a case of a patient with clival chordoma.

Example case

Chief complaint: deviated tongue and neck stiffness

History of present illness

A 21-year-old, right-handed woman with no significant past medical history presented with deviated tongue and neck stiffness. Three months prior, she was involved in a motor vehicle collision, and since then has complained of neck stiffness. However, 7 days prior to evaluation, she noticed that her tongue deviated to her left. She was seen at a local emergency room for stroke evaluation, and imaging revealed a skull base lesion ( Fig. 66.1 ). She underwent endonasal biopsy consistent with chordoma.

Medications : Diazepam.
Allergies : No known drug allergies.
Past medical and surgical history : None.
Family history : No history of intracranial malignancies.
Social history : Military, no smoking or alcohol.
Physical examination : Awake, alert, oriented to person, place, time; Cranial nerves II to XI, except left tongue deviation; Moves all extremities with good strength.

	William T. Couldwell, MD, PhD, University of Utah, Salt Lake City, UT, United States	Paul A. Gardner, MD, Carl H. Snyderman, MD, MBA, University of Pittsburgh, Pittsburgh, PA, United States	Gerardo D. Legaspi, MD, Philippine General Hospital, Manila, Philippines	Henry W. S. Schroeder, MD, PhD, University of Greifswald, Greifswald, M-V, Germany
Preoperative
Additional tests requested	High-resolution CT Swallowing evaluation	High-resolution CT CT angiogram ENT evaluation Spine MRI	High-resolution CT	CT scan to assess stability of craniocervical junction
Surgical approach selected	Extreme lateral transodontoid resection, occipital-cervical fusion	Endoscopic endonasal transclival, left transpterygoid, possible partial transodontoid	Left suboccipital craniotomy with far lateral extension	Endoscopic endonasal transclival, occipital-C2 fusion
Other teams involved during surgery	ENT	ENT	None	ENT
Anatomic corridor	Extreme lateral transodontoid	Transnasal, transclival, left transpterygoid	Left far lateral transcondylar	Transnasal, transclival
Goal of surgery	Radical resection	Radical resection	Maximal safe resection	Radical resection
Perioperative
Positioning	Left lateral	Supine with right rotation	Left lateral	Supine for endonasal; prone for fusion
Surgical equipment	IOM (MEP, SSEP, cranial nerves IX–XII) Surgical navigation Ultrasonic aspirator	IOM (SSEP) Surgical navigation Endoscope Microdoppler	Surgical microscope Ultrasonic aspirator	Surgical navigation Endoscope Microdoppler
Medications	Steroids	Steroids	None	None
Anatomic considerations	Hypoglossal nerve, brainstem, odontoid, anterior arch C1, vertebral artery	Parapharyngeal ICAs, Eustachian tubes, hypoglossal canals, inferior petrosal sinus, foramen lacerum, vertebrobasilar junction	Hypoglossal nerve, lower cranial nerves, vertebral artery	Cranial nerves IX–XII, vertebral artery
Complications feared with approach chosen	Lower cranial nerve injury	Lower cranial nerves and vertebrobasilar injury	Brainstem injury, vertebral artery injury	Injury to petrosal carotid artery and lower cranial nerves
Intraoperative
Anesthesia	General	General	General	General
Skin incision	L-shaped inverted hockey stick	None	Linear 3 cm medial to mastoid from transverse sinus to C2	Midline posterior for fusion
Bone opening	Left retrosigmoid suboccipital, posterior arch/lateral mass/condylar joint of C1, C2 lamina/superior articular process/odontoid	Sphenoidotomy, bilateral maxillary antrostomy, left pterygoid wedge, left vidian canal, middle/lower clivus, left hypoglossal canal	Left retrosigmoid incorporating foramen magnum, left occipital condyle, partial anterior petrosectomy	Sphenoidotomy, clivus, anterior arch of C1 and infiltrated dens
Brain exposure	Extreme lateral	Transclival	Far lateral transcondylar	Transclival
Method of resection	L-shaped incision, identify suboccipital triangle, release muscle attachments to C1 transverse process to identify vertebral artery and C1 root, division of the C2 root and transpose vertebral artery, small retrosigmoid suboccipital craniectomy, inferior foramen magnum removed to identify dural entry of vertebral artery, posterior arch/lateral mass/condylar joint of C1 drilled, remove anterior C1 ring, drill C2 lamina and superior articular process, remove odontoid, debulk tumor, leave dura intact, identify and preserve hypoglossal nerve, occipital-cervical fusion	Lateralize inferior turbinates, harvest right extended nasoseptal flap, wide sphenoidotomy, left maxillary antrostomy, open left pterygopalatine space, right maxillary antrostomy, nasal sleeves, inverted U nasopharyngeal/retropharyngeal flap down to anterior arch of C1, displace left pterygopalatine contents laterally to locate vidian canal, drill base of pterygoid/medial pterygoid wedge until flush with paraclival ICA, drill sphenoid rostrum and middle/lower clivus above pole of tumor, dissect until lateral margins identified, biopsy to confirm chordoma, localize left parapharyngeal ICA with Doppler, peel lateral prevertebral/preclival tumor from parapharyngeal space, resect bulk of tumor, inspect for residual, drill bony margins, dissect foramen lacerum, stimulate left hypoglossal nerve to clear tumor in canal and drill surrounding bone, drill tip of C2 as needed, resect inner layer of dura if involved, reconstruct dura with collagen inlay/fascia lata, fat graft to fill nasopharynx, nasoseptal and retropharyngeal flaps to protect lower borders, ICG endoscopic angiography to confirm vascularization, placement of lumbar drain	Linear incision carried down to periosteum, dissect and isolate left extracranial vertebral artery in areolar space, retract muscle flap laterally to sigmoid space and medially near midline, burr hole on the asterion, craniotomy flap, complete foramen magnum removal with drilling and bone punching, extend to the precondylar area with special extension to the hypoglossal nerve, partial anterior petrosectomy to expose more extradural tumor, debulk and excise tumor using combination of sharp and blunt dissection assisted by ultrasonic aspirator, attempt total excision and debulk maximally, close in layers	Harvest nasoseptal flap on right, reverse flap on left, enter sphenoid sinus, drill out clivus, resect tumor as far laterally and dorsally as possible, incise nasopharynx mucosa and create a flap, resection anterior arch of C1 and infiltrated dens, close defect with fat and nasoseptal flap/fibrin glue/nasal pledgets, reposition patient in prone position, midline skin incision and fusion with occipital plate-lateral mass of C1 and lamina of C2 after resection of dorsal part of condyle
Complication avoidance	Large incision for fusion, early identification of vertebral artery, mobilization of vertebral artery, identification/preservation of hypoglossal nerve, occipital-cervical fusion	Harvesting nasoseptal and retropharyngeal flaps, drill out for bony margins, inspect hypoglossal canal, multilayer dural reconstruction, ICG vascular flap assessment	Isolate vertebral artery, large craniotomy, far lateral transcondylar extension, anterior petrosectomy	Neuro-monitoring, navigation, harvest nasoseptal flap, drill out margins, multilayer closure
Postoperative
Admission	ICU	Intermediate care or ICU	Floor	Intermediate care
Postoperative complications feared	Lower cranial nerve injury	CSF leak, worsened dysphagia, aspiration, craniocervical instability	Hypoglossal nerve injury, lower cranial neuropathy	CSF leak
Follow-up testing	MRI within 24 hours after surgery Swallow evaluation	Lumbar drain for 72 hours High-resolution CT within 1 day after surgery Swallow evaluation MRI within 48 hours after surgery	MRI within 48 hours after surgery	MRI within 24 hours after surgery CT within 24 hours after surgery
Follow-up visits	1 month after surgery	1 week after surgery with ENT 2 weeks after surgery with neurosurgery	1 week after surgery	3 months after surgery for neurosurgery Continual follow-up with ENT after surgery
Adjuvant therapies recommended	Reoperation to achieve gross total resection, proton beam radiation	Reoperation to achieve gross total resection, proton beam radiation	Proton beam radiation therapy	Reoperation to achieve gross total resection, radiation with proton beam or carbon ion radiation after 3 months