Tumors of the Spine

• The spine is the frequent site for metastasis
• Certain tumors have a unique manifestation in the vertebrae
• Malignant tumors most common in lumbar spine (lumbar > thoracic > cervical)
• Malignant tumors more commonly in vertebral body than posterior elements

Metastatic breast cancer

Metastasis

• Most common tumors of the spine
• Spread to vertebral body first, then later to pedicles
• Breast, lung, and prostate cancers are most common

Signs/Symptoms of Metastasis:

• History of cancer
• Recent unexplained weight loss
• Night pain
• Age > 50 years

Radiographic appearance of Metastasis:

• Most are osteolytic
• Prostate cancer is an osteoblastic tumor (osteoid forming tumor)
• Most not visible on plain radiographs until > 30% of vertebral body destruction

Treatment of Metastasis:

• Prognosis is poor if neurologic dysfunction, proximal lesions, long duration of symptoms, rapid growth of lesions
• CT-guided needle biopsy performed when possible, surgery avoided
• Radiation and Chemotherapy mainstays
• Prostate and lymphoid tumors are very radiosensitive
• Breast cancer is 70% radiosensitive, 30% resistant
• GI and renal cell tumors are usually radioresistant
• Surgical indications:
• Progressive neurologic dysfunction unresponsive to radiation therapy
• Persistent pain despite radiation
• Need for diagnostic biopsy
• Pathologic fracture/dislocation
• Life expectancy should dictate whether or not surgical treatment is preformed
• For instability/neurologic deficit, anterior decompression and stabilization often used

Primary Tumors

Tumors of the Vertebral Body:

• Eosinophilic Granuloma
• Usually seen in children <10 years
• Predilection for thoracic spine
• Causes progressive back pain
• Classically causes vertebral flattening, vertebra plana – Calve’s disease, seen on lateral radiograph
• Treatment:
• Chemotherapy for systemic histiocytosis
• Bracing to prevent progressive kyphosis
• Low-dose radiation may be indicated in presence of neurologic deficit
• Most symptoms are self-limited
• 50% reconstitution of vertebral height expected
• Giant Cell Tumor
• Most commonly seen in 4^th-5^th decade of life
• Expansile destruction of vertebral body
• Surgical excision and bone grafting recommended treatment
• High recurrence rate reported
• Radiation therapy should be avoided due to risk of malignant degeneration

Giant cell tumor of the L3 vertebral body

• Chordoma
• Low-grade lytic lesion in midline of sacrum or base of skull
• May occur in vertebrae
• Patients present with intra-abdominal complaints and pre-sacral mass
• Treatment: Radiation and Surgery
• Surgical excision may include unilateral resection of all sacral nerve roots
• Bowel and bladder function can be preserved by unilateral root resection
• High recurrence rates

CT scan of sacrococcygeal chordoma

• Osteosarcoma
• Uncommon in spine (all primary malignant skeletal lesions)
• Poor prognosis
• Treatment: Radiation and chemotherapy
• Aggressive surgical excision occasionally performed

• Hemangioma
• Usually asymptomatic
• Small fractures may be present in symptomatic patients over age 40
• Radiographic appearance:
• “Jailhouse striations” seen on plain films
• “Spikes of bone” seen on CT
• Vertebrae normal sized, not expanded as in Paget’s
• Treatment
• Observation unless painful pathologic fracture present
• Anterior resection and fusion if posterior collapse
• Massive bleeding frequently encountered
• Marrow cell tumors: Multiple Myeloma & Plasmacytoma
• Common in spine
• Osteopenic, lytic lesions
• Pain, pathologic fractures and diffuse osteoprosis present
• Increased serum calcium levels
• Decrease hematocrit
• Abnormal protein studies (serum/urine electrophoresis)
• Treatment mainstay is radiation therapy (3000-4000 cGy +/- chemo)
• Surgery reserved for instability or refractory neurologic symptoms

Tumors of the Posterior Elements:

• Osteoblastoma and Osteoid osteoma
• Common in the spine
• May present as painful scoliosis in children – lesion is typically at apex of convexity
• Pain is typically relieved by non-steroidal anti-inflammatory drugs (NSAIDs)
• Bone scan helps localize
• Thin-cut CT scan directs surgical intervention
• Surgery indicated with scoliosis, curve resolves within 18 months of resection in children <11 years old
• NSAIDs are mainstay of treatment if no scoliosis present
• Resection performed if pain uncontrolled by NSAIDs
• Osteoblastomas common in posterior elements of older patients
• Neurologic involvement in 50%
• Resection and posterior fusion typically required

Osteoid osteoma of L3 vertebra in patient 9 years of age with back pain and mild scoliosis. Sclerotic lesion is seen in pedicle of L3 on concave side of curve.

• Aneurysmal bone cyst
• Cysts typically detected during second decade of life
• May represent degeneration of more aggressive tumors
• Can occur in posterior or anterior elements (vertebral body)
• Treatment is excision and/or radiation therapy

Imaging:

• Plain radiographs
• Radiographic changes include absent pedicle, cortical erosion or expansion, and vertebral collapse
• MRI also useful: malignant tumors have decreased T1 and increased T2 intensity
• MR sensitivity increases with use of gadolinium

Treatment:

• Complete resection is difficult
• Treatment usually comprises tumor debulking with stabilization
• Adjuvant chemotherapy and radiation are necessary