Treatment Strategies for Spine and Spinal Cord Tumors

Matt El-Kadi, MD, PhD.

Professor, Chief of

Department of Neurosurgery

UPMC Passavant Hospital

Discussion Topics

Incidence of Spine Tumors

Has been estimated to be between 2.5 and 8.9 tumors per 100,000 population per year

Types of Primary Tumor of the Spine

Benign lesions: 

Ostoid osteoma, osteoblastoma, aneurysmal bone cyst, osteochondroma, etc.

Malignant lesions: 

Ewing’s tumor, chondrosarcoma, malignant lymphoma, angiosarcoma, etc

Clinical Presentation and Diagnostic Challenge

Axial pain – worse at night

Radiculopathy, myelopathy

Spinal instability

Indirect signs – Osteoma reported to be the most common cause of painful scoliosis

Why Benign Spine Lesion – are a diagnostic challenge

Slow growing pattern of lesion and subtle symptoms

Duration of symptoms to diagnose in osteoma, osteochondroma, and aneurysmal bone cyst in 6 – 30 months

Spine tumors are very rare and often accompanied with degenerative disc disease

Diagnosis of Primary Spine Lesions

Spine X-ray

MRI (patient with spine related complaints)

CT scan (provide more information for differential diagnosis and surgical planning)

Bone Scan and Spect/CT:  Precise localization and extent of lesion for diagnosis and surgical planning

CT guided biopsy 

Treatment Team may Include:

Neurosurgeon

Cardiothoracic and General surgeon

Neuroradiology

Oncology Specialist

Physical Rehab

Pre-operative Planning

Tumor location and extension

Involvement of the adjacent structures

Tumor vascularity and preoperative embolization

Stability of the Spine

Primary Spine Tumor

Spinal resection is for cure not palliative surgery

Only an experienced surgeon and multi-disciplinary approach provide the patient with the best outcome

Spinal Tumors Locations

Extradural

Intradural

–    Extramedullary

–    Intramedullary

Benign Tumors

Have slow growing pattern, by the time diagnosed, tumor is already compressing on neural structures and presenting with neurological deficit

 

Spinal tumors are easy to be missed because they are rare and can occur in conjunction with other spinal disease like HNP, lumbar and cervical stenosis, OPLL, Chiari Malformation

Intradural Extramedullary Tumors

Schwannoma

Meningioma

Ependymoma of filium terminale

Intradural Extramedullary Tumors Clinical Manifestations

Depends on location (Cervical, Thoracic, Lumbar)

Intradural Extramedullary Tumors: Preoperative Planning

Precise localization of tumor with placement of skin marker under fluoroscopic guidance (thoracic and upper lumbar)

Standard laminectomy with ½ level above and below the tumor

Necessary adjuncts for surgery

EMG, SSEP, CUSA, Spine fixation

Peri-operative Steroids

Intraoperative Pitfalls

Avoid hypotension in already compromised spinal cord

Surgical field absolutely clean and dry before opening the dura

Dural opening (meningioma, schwannoma and other)

Extension of dural opening and dural tack up sutures

Arachnoid membrane (open separately from dura, relation to meningioma

Advantages of “Lazy S” off center Dural Opening

Preservation of arachnoid membrane in the midline and prevention of possible cord tethering in the future

Direct access to dural attachments

Minimizing cord manipulation and compression by getting better angle for tumor removal

Tumor Resection

Identify the inferior and superior margins of tumor

Block CSF above and below with gelfoam and patty

En block resection vs. gradual debulking

Ventral-lateral located tumor that requires cord mobilization – cut the dentate ligament at its insertion in the dura above and below the tumor

Fibrous or partially calcified tumor – balance between total resection and post-operative morbidity

Intramedullary Tumor

Approximately 15% of all primary intradural tumors are intramedullary

Astrocytoma and Ependymoma are the most common

Hemangioblastoma – less common

Clinical Manifestations of Intramedullary Tumors

Sensory deficit antedate the motor symptoms

Symptoms resemble syringomyelia

Cervical intramedullary tumors present initially with lower motor neuron deficits (Involvement of anterior horn cells)

Weakness in lower extremities follows upper extremities symptoms

Hydrocephalus may occur in up to 12.5 %

Differential diagnosis – MS, (more rapid onset, remission and exacerbation, oligoclonal bands)

Decision Making in the Treatment of Intramedullary Tumors

The diagnosis of intramedullary tumors doesn’t mandate operative procedure

Patients who can’t stand – very unlikely to regain motor function to enable them to ambulate after surgery

Patient with complete motor and sensory deficits will not regain function after surgery

Surgery for anaplastic intramedullary astrocytoma do not appear to be beneficial

Intraoperative Management of Intramedullary Tumors

Evoke Potentials:

–     SSEP – alone are not useful in guiding the surgeon during surgery

–     Patient with profound sensory deficits have SSEP either absent or low amplitude where meaningful recording cannot be obtained

–     The delay of response 1 to 60 sec, to observe the waveform changes makes no difference in complication prevention

–     Therefore, SSEP should be combined with motor evoke potentials, so stimulation and recording of both (sensory and motor) pathways may be used for complete assessment of spinal cord function.

–     Mapping spinal cord motor tracts facilitates the extend of surgical resection

How to Define the Midline for Myelotomy

With intramedullary tumors cord can be distorted and rotated

The midline is visualized by identifying the branches of the dorsal medullary vein penetrating medial sulcus

The midline is midway between the left and right dorsal roots

Sometimes antidromically elicited SSEP with evoke stimulation may help the midline where is no response

Surgical Pitfalls for Intramedullary Tumors

Precise localization of the tumor nodule before opening the dura and before performing myelotomy (MRI, intraoperative ultrasound)

Myelotomy – over the area of solid tumor (not cyst)

The pia-arachnoid and dorsal surface of the cord is incised sharply to the depth of 2-3 mm and held apart by 6-0 atraumatic suture through the pia-arachnoid

Astrocytoma

Approx. 30% of intrinsic spinal tumors

More common in children

Pilocystic variants have definable surgical planes.  The rest have ill definable planes

Resection should be carried from inside out

Ependymoma

Most common intramedullary spine tumor in adult

Usually has definable plane

Outcome and survival depends on total resection

50% above the conus, 50% associated with filum terminale, cauda equina and conus medullais

Surgical goal is gross total resection

Risk of dissemination through CSF pathways

Conclusion

Multidisciplinary approach and precise preoperative planning and gross total resection provide the patient with the best outcome

Call, toll-free, at 412-630-7640 or 877-635-5234 to learn more.

Disclaimer:

Every effort has been made by the author (s) to provide accurate, up-to-date information. However, the medical knowledge base is dynamic and errors can occur. By using the information contained herein, the viewer willingly assumes all risks in connection with such use. Neither the author nor UPMC shall be held responsible for errors, omissions in information herein nor liable for any special, consequential, or exemplary damages resulting, in whole or in part, from any viewer(s)' use of or reliance upon, this material.

CLINICAL DISCLAIMER:

Clinical information is provided for educational purposes and not as a medical or professional service. Person(s) who are not medical professionals should have clinical information reviewed and interpreted or applied only by the appropriate health professional(s).

For questions or comments, please contact: bostj@upmc.edu

Updated: August 26, 2007