METASTATIC LESIONS OF SPINE

Dr. Sushil Paudel

Metastatic tumour - most common malignancy of bone

Spine - most common site of osseous metastases

5-10% of the patients with cancer develop spine metastases*

All age groups with highest age incidence in between 40 and 65 years

Male:Female – 3:2

*Ries LAG, Melbert D, Krapcho M, et al, eds. SEER Cancer Statistics Review,1975–2005. National Cancer Institute. Bethesda

LOCATION◦ Thoracic spine (60-

80%)◦ Lumbar spine (15-

30%)◦ Cervical spine (<10%)

PRIMARY*◦ Unknown(33%)◦ Breast (21%)◦ Lung (14%)◦ Prostate(8%)◦ Gastrointestinal (5%)◦ Thyroid (3%)

*Ries LAG, Melbert D, Krapcho M, et al, eds. SEER Cancer Statistics Review,1975–2005. National Cancer Institute. Bethesda

Basis of anatomic location* Intradural - 5%

◦ Intramedullary◦ Extramedullary – tertiary

drop metastases

Extradural - 95%◦ Pure epidural – rare◦ Arising from the vertebrae -

most frequent

*Perrin RG, Laxton AW. Metastatic spine disease:epidemiology, pathophysiology, and evaluationof patients. Neurosurg Clin N Am 2004;15:365–373

Intramedullary extradural metastases entrapped in cauda equina

Metastatic properties of primary neoplasia Anatomic properties of the host organism Biologic properties of the skeletal host

Posterior half of the body is seeded first, anterior half, pedicles and lateral masses are involved later

Local spread to adjacent vertebra Spread to epidural space Induce osteoblastic or lytic lesions, diffuse

osteopenia or variable combination Replacement of marrow tissue with

neoplasm, progressive collapse and finally spinal instability

Pain – 85%◦ Constant and

localised◦ Radicular◦ Axial

Spinal deformity Neurologic deficit Constitutional

symptoms

RED FLAG features– Gradual onset, progressive, constant, night time or recumbency pain and axial pain exaberated by movement in all directions

History Physical examination Laboratory studies Imaging studies

HISTORY◦ Nature of patient’s symptoms and their onset◦ Exposure to possible carcinogens◦ Family history◦ Review of other systems

PHYSICAL EXAMINATION◦ Comprehensive◦ Should palpate for

masses diagnostic of a primary breast, thyroid, prostate, or rectal carcinoma

LABORATORY STUDIES◦ Complete blood counts◦ Serum chemistry◦ ESR◦ Serum and urine protein

electrophoresis◦ Serum tumour markers-

PSA, CEA, CA 19-9, AFP◦ Mammography◦ Bone marrow biopsy

IMAGING STUDIES Plain radiographs Bone scan CT scan of chest,

abdomen, pelvis and of the suspicious area

MRI PET scan

History and physical examination

Local plain films, chest radiographsand Laboratory tests

Suspicious or no lesion

Bone scan

Bone scan

Polyostotic Monostotic

CT scan/MR imaging Perform biopsy

Impending fracture

No impending fracture

Perform biopsy and stabilise

Observe, radiate or perform biopsy

Biopsy

Primary sarcomaMetastatic carcinoma

Refer to sarcoma surgeon

Renal or thyroid primary

Non Renal or thyroid primary

Treat as indicated

History and physical examinationChest radiographs and Laboratory tests

MyelomaPrimary not identified

Primary identified

Stage and as indicated

Bone scan, CT scan of chest, abdomen

and pelvis

Skeletal survey; Refer to medical

oncologist

Bone scan; CT scan of chest, abdomen and pelvis

Primary identified

Solitary lesion and primary

not identified

Multiple bone lesions and Primary n0t identified

Assume sarcoma;Refer to

orthopaedic oncologist

Perform biopsy on most appropriate

site

Stage and treat as

indicated

Diagnostic imaging

Biopsy

PLAIN RADIOGRAPHS◦ Location◦ Pattern of bone destruction◦ Vertebral collapse◦ Winking owl sign ◦ Difficult to detect early lesions

BONE SCAN◦ Superior sensitivity◦ Extent of dissemination◦ Define the most accessible lesion

to biopsy in cases of unknown primary

SPECT

COMPUTED TOMOGRAPHY◦ Improved specificity ◦ Sensitive to alterations in

bone mineralisation◦ Osseous details ◦ Evaluation of cortical

penetration

MAGNETIC RESONANCE IMAGING◦ Superior sensitivity and specificity◦ Method of choice to evaluate spine ◦ Define the intramedullary, intradural and extramedullary lesions ◦ Extent of the lesion ◦ Differentiation from other

pathologies such as infection and osteoporotic ◦ Fat suppression and Gadolinium

enhancement to improve the delineation

POSITRON EMISSION TOMOGRAPHY◦ Uses Flourine-18-Flouro deoxy

glucose◦ MRgIc calculation by Patlak

analysis in ROI◦ Detection of primary and

metastatic tumours◦ Recurrences of tumour◦ Differentiation of osteoporotic

VCF from pathologic VCF’s

Tissue diagnosis of lesion guides the treatment

FNAC or needle biopsy Core biopsy Incisional biopsy Excisional biopsy

PER CUTANEOUS APPROACHES FOR BIOPSY

Posterior cervical

C 1 – 3= Transoral

Sub axial cervical

Anterior or posterior to sternocleidomastoid

Thoracic and Lumbar

Transpedicular or Postero lateral

Sacral Posterolateral

DIRECTED TO PRIMARY

LUNG CANCER Metastatic stage IV – dismal

prognosis, median survival < 6 months

◦ Small cell LC Chemotherapy Radiotherpy

◦ Non small cell LC Combined chemo and

radiotherapy Resection of the tumour with

vertebrectomy

PROSTATE CANCER Hormone withdrawal –

bilateral orchidectomies or androgen deprivation (LHRH agonists, flutamide etc)

Radiation therapy Chemotherapy Surgery Average survival around

12 months

BREAST CANCER Metastatic cancer –

median survival 3 years Chemotherapy Hormonal therapy –

Tamoxifen Bisphosphonates

THYROID CANCER Thyroidectomy followed by

iodine – 131 at therapeutic doses

Palliative radiotherapy Overall 10 year survival

rate – 35%

RENAL CELL CARCINOMA Metastatic – median

survival 6 to 9 months Combined

chemo/immune therapy Radiotherapy Pre operative

Embolisation and Surgery

DIRECTED TO SPINAL LESION

Early 1900’ s – surgical treatment such as decompressive laminectomy

1953 - first patient was treated with a linear accelerator

1980’ s – advent of spinal implants Recent developments - Intensity-modulated

radiation therapy (IMRT), stereotactic radiosurgery, and stereotactic radiotherapy

Life expectancy Biopsy – Histology to predict the response

to non operative management Stability Clinical presentation – Pain and Neurological

status

Analgesic treatment Physical therapy and bracing Bisphosphonates Vertebroplasty or Kyphoplasty Radiofrequency ablation Radiation therapy Surgical stabilization in patients with life

expectancy of more than 3 months

PATIENTS PRESENTING WITH PAIN AND NO NEUROLOGICAL DEFICIT

ANALGESIC TREATMENT Three Step model of analgesia

◦ NSAIDS◦ Short acting opioids◦ Pure opioid agonists

Disease-modifying therapies, coanalgesic/adjuvant administration, and interventional strategies (cognitive, behavioral, physiatric etc)

BISPHOSPHONATES Treat hypercalcemia Potent inhibitors of normal and

pathological bone resorption. Antiangiogenic effects and

Antitumoral activity*PHYSICAL THERAPY AND BRACING Orthoses Bracing

*Diel IJ, Solomayer EF, Costa SD, et al: Reduction in new metastases in breast cancer with adjuvant clodronate treatment. N Engl J Med 339:357–363, 1998

Emergency whole spine MRI

Dexamethasone

Radiosensitivity+ -

Unstable spine

VertebroplastyOr

Kyphoplasty

Radiotherapy

Neurological deficit<24 hrs

Surgical candidate

_

+

-

Surgical decompression and stabilization followed by

radiotherapy

+

CORTICOSTEROIDS Should be prescribed in

all patients presenting with neurological deficit◦ High dose

dexamethasone◦ Standard dose ◦ Methyl prednisolone

General indications

EXTERNAL BEAM RADIOTHERAPY◦ Pain-Single fraction radiotherapy◦ Neurological deficit-short course

and long course regimens Intra operative brachytherapy Cobalt-60 teletherapy Injectable radioisotopes Megavoltage therapy Proton/neutron/electron

bombardment

IMRT, STEREOTACTIC RADIOSURGERY AND STEREO TACTIC RADIOTHERAPY*◦ Deliver high doses safely◦ Possible to irradiate spine without affecting spinal

cord

*De Salles AA, Pedroso AG, Medin P, Agazaryan N, Solberg T,Cabatan-Awang C, et al: Spinal lesions treated with Novalisshaped beam intensity-modulated radiosurgery and stereotacticradiotherapy. J Neurosurg 101 (3 Suppl):435–440, 2004

(A) Target planning image. The thick dark pink line surrounds the target volume. The thick dark green line represents the thecal sac (main organ at risk). The remaining lines represent isodose lines. (B) Dose-volume histograms demonstrating steep falloff of radiation, with high doses being applied to the lesion and a low volume of the thecal sac being exposed to significant dose.

SYSTEMIC RADIOISOTOPE THERAPY◦ Strontium – 89, Samarium -

153 and Rhenium – 186◦ Affinity to osteoblastic bone ◦ Local antitumour activity

and analgesic affect*

*Serafini AN: Systemic metabolic radiotherapy with samarium-153 EDTMP for the treatment of painful bone metastasis. Q J Nucl Med 45:91–99, 2001

Injection of PMMA into the involved vertebral body under fluoroscopic guidance.

Reinforcement of the bone and stabilization of anterior column relieves pain

PMMA – Anti tumour activity

MECHANISM OF PAIN RELIEF*◦ Stabilization of microfractures◦ Reduction of mechanical forces ◦ Destruction of the nerve terminals by the

cytotoxicity of PMMA

*Cotten A, Dewatre F, Cortet B, et al. Percutaneous vertebroplasty for osteolytic metastases and myeloma: effects of the percentage of lesion filling and the leakage of methyl methacrylate at clinical follow-up. Radiology 1996;200:525–530

Percutaneous introduction of a KyphX balloon Inflated to reduce the fracture and deflation Void filled with PMMA

Low extravasation rate

Pain relief equivalent to that of vertebroplasty

Can restore the lost vertebral height

Can correct the sagital balance

Can use more viscous cement

Increases the vertebral body strength

Increases the vertebral body stability

Can provide tissue for diagnosis

ADVANTAGES

Uses thermal energy to destroy the tumour cells

Combined treatment with vertebroplasty*

*Schaefer O, Lohrmann C, Markmiller M, Uhrmeister P, Langer M. Technical innovation: combined treatment of a spinal metastasis with radiofrequency heat ablation and vertebroplasty. Am J Roent 2003;180:1075–1077

Radiofrequency Ablation Probe at T9Anterior-posterior (a) and lateral (b) fluoroscopic images of the radiofrequency ablation probe in the T9 vertebral body

Radiofrequency ablation combined with vertebroplasty/kyphoplasty

Tumour debulking combined with VB augmentation ◦ Ablation using LITT (laser induced thermotherapy)

before cement placement *

*Ahn H, Mousavi P, Chin L, et al. The effect of pre-vertebroplasty tumor ablation using laser-induced thermotherapy on biomechanical stability and cement fill in the metastatic spine. Eur Spine J 2007;16:1171–78. Epub 2007 Apr 20

A 71-year-old woman with undifferentiated cancer and a lesion at L4. B and C, A void is created in the vertebral body by debulking the spinal tumor using the plasma radio-frequency– based wand before vertebral body augmentation with bone cement. D–F, Axial (D and E) and sagittal (F) views by using MR imaging show excellent anterior placement

Vertebral body augmentation combined with hardware*◦ Short segment pedicle screw fixation combined

with vertebroplasty/kyphoplasty in lieu of traditional long segment fusion

*Cho DY, Lee WY, Sheu PC. Treatment of thoracolumbar burst fractures with polymethyl methacrylate vertebroplasty and short-segment pedicle screw fixation.Neurosurgery 2003;53:1354–60, discussion 1360-61

GOALS◦ Obtaining tissue in case

of an unknown diagnosis

◦ Relief of neurologic symptoms by decompression

◦ Relief of pain by stabilization and reconstruction of the spinal column

Pre operative for vascular metastatic lesions such as renal cell, thyroid carcinoma, squamous and adenocarcinomas of lung

Resection Decompression Reconstruction and stabilization

Radiation- and chemotherapy-resistant tumors (e.g., squamous and renal

cell)

Acute or progressive spinal cord compression

Recurrent tumor in patients who have already received maximal doses of

chemotherapy/radiation

Pain associated with collapse in vertebral height of greater than 50%, a 50% kyphotic

deformity, or more than 70% of the vertebral body destroyed

Isolated metastases in which durable remissions can potentially be achieved (e.g.,

renal, breast, thyroid)

Impending fracture

SCORING SYSTEMS Karnofsky score estimates a patient's ability

to carry out normal activities, work, and care for themselves.

The Tokuhashi index◦ Karnofsky index◦ Neurologic status◦ Metastatic disease◦ Cancer type◦ Surgical resectability.

Total Tokuhashi score Life expectancy

   0–4    <3 mo

   5–8    <6 mo

   9–12    >6 mo

Tokuhashi score is developed as an assessment tool to select the most suitable surgical procedure with respect to predicted prognosis

Tomita classification- built on Enneking oncological system

Description of the affected site Metastatic extent

◦ Intracompartmental(1-3)◦ Extracompartmental(4-7)

1. Vertebral body

2. One or both pedicles

3. Lamina and spinous process

4. Epidural canal

5. Paravertebral area

6. Adjacent vertebra

7. Skip lesions

Tokuhashi

score Life expectancy

Tomita

classification Surgical procedure (all receive radiation)

0–4 <3 mo 1–7 Laminectomy and stabilization

5–8 3–6 mo 1–7 Posterior decompression, stabilization, and

reconstruction

9–12 >6 mo 1–3 En bloc with vertebrectomy and 360-degree

reconstruction

4–6 Intralesional vertebrectomy and 360-degree

reconstruction

7 Posterior decompression and stabilization

Location of the tumour Spinal instability Neurological status

James weinstein model

Zones IB to IVB – Extraosseous extensions of the tumour beyond cortical boneZones IC to IVC - Associated regional or distant metastases

• Zones I and II lesions - posterior or posterolateral surgical approach Zone III lesions – anterior surgical approach Zone IV lesions - combined anterior and

posterior approach

SURGICAL APPROACHES LEVEL ANTERIOR POSTERIOR

Upper cervical Transoral, Extraoral, Extreme lateral

Midline

Lower cervical Southwick Robinson Midline

Cervicothoracic Sternal splitting, Low costotransversectomy

MidlineCostotransversectomy

Thoracic ThoracotomyCostotranversectomy

CostotransversectomyTranspedicular

Thoracolumbar 11th rib extrapleural retroperitoneal

MidlinePosterolateral

Lumbar RetroperitonealTransabdominal

Midline,TranspedicularPosterolateral

RECONSTRUCTION AND STABILIZATION◦ Anterior◦ PosteriorSubclassified according to the level

THORACIC SPINE Disease involving vertebral body at 1 or 2

levels- Transthoracic vertebrectomy and anterior reconstruction

Single stage posterolateral decompression and stabilisation – patients with specific contraindication to thoracotomy

Significant kyphosis with VB collapse, disease involving DL junction – posterior stabilization with anterior reconstruction

Inclusion of significant portion of chest wall in tumour resection – posterior stabilization to prevent the risk of kyphoscoliosis

Cases of tumours involving VB posterior elements and chest wall – combined approach for resection and VB reconstruction, anterior and posterior stabilization

INSTRUMENTATION Fixation using rods and screws Vertebral body reconstruction – metal cage,

cement, ceramic spacer, or grafts( autologous or allograft)

57 year old female of lung carcinoma with metastases D5 underwent circumferential tumor resection and simultaneous anterior and posterior reconstruction by combined approach.

LUMBAR SPINE Standard retroperitoneal approach –

excellent exposure Single level L1-3 disease – vertebrectomy

and anterior reconstruction Disease limited to L5 – posterolateral

decompression and stabilisation Multilevel disease – palliative posterolateral

decompression

LUMBOSACRAL JUNCTION AND SACRUM Resection and reconstruction by pedicle screws

and rods by modified Galveston technique

Cure is not the goal

Multidisciplinary approach

Surgery vs Radiotherapy*

Management often not clear cut

Patchell RA, Tibbs PA, Regine WF et al. Direct decompressivesurgical resection in the treatment of spinal cordcompression caused by metastatic cancer: a randomisedtrial. Lancet 2005;366:643-8.

Adult and Pediatric spine, 3rd edition Spinal Extradural metastases; Review of

current treatment options.CA Cancer J Clin 2008;58;245-259

Spinal instability and deformity due to neoplastic conditions.Neurosurg Focus 14 (1):Article 8, 2003

Bone metastases.Tumors