management of spinal metastases
TRANSCRIPT
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Management of Spinal Metastases
Enric Cáceres Palou
Contents
General Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4310
Aetiology and Classification . . . . . . . . . . . . . . . . . . . . . . 4311
Applied Biomechanics, Pathology and Basic
Science . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4311
Metastatic Tumour Cells .. .. .. .. .. .. .. .. .. .. .. .. .. . 4311
Angiogenesis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4312
Invasion of Soft Tissue .. . . . . . . . . . . . . . . . . . . . . . . . . . . . 4313
Bone Resorption . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4313
Mechanism of Spinal Cord Compression .. .. . . .. . . 4314
Diagnosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4314
PET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4315Treatment of Spinal Metastases and Indications for
Surgery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4318
Steroids . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4318
Chemotherapy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4318
Radiation Therapy .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4318
Surgical Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4318
Indications and Contra-Indications . . .. . . . .. . . . . . . . 4319
Operative Technique . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4319
Vertebroplasty and Kyphoplasty . .. .. .. .. .. .. .. .. .. 4319
Decompression and Instrumentation . . . . . . . . . . . . . . . 4319
En Bloc Resection .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4322
Complications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4322
Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4322
References . . . . . . . . . . . .. . . . . . . . . . . .. . . . . . . . . . .. . . . . . 4322
Abstract
Metastatic spine tumours (MST) cause the lossof the supporting function of the spine through
vertebral destruction or invade and compress
the spinal cord or cauda equina. As a result,
metastatic spine tumour causes severe pain,
paralysis and decreased of quality of Life
(QOL). For this reason treatment is primarily
symptomatic and the major goals in selecting
therapeutic modalities are to relieve pain,
prevent paralysis and improve activities OD
daily living (ADL).Four main circumstances influence MST
treatment: continuous improving in survival,
changes in prevalence of the disease, multidis-
ciplinary dependence and evidence of
literature. Mortality rates continue to decrease
year-by-year for three most common sites in
men (lung, colorectal and prostate) and in
women fort breast and colorectal. Around
1.5 % for men and 0.8 % for women.
Analysing MST, the multidisciplinarydependence, with different approaches,
different attitude, especially different world
literature, medical oncologists, palliative
care, radiotherapists, epidemiology health
experts, neurosurgeons and the Orthopaedic
community means that the interpretation of
results and advice to the patient can be
confusing.
The optimal management of MST is con-
troversial, a multidisciplinary approach withaccording to assess neurological and oncolog-
ical symptoms, mechanical stability and
E. Cáceres Palou
Department Hospital Vall d’Hebron, AutonomousUniversity of Barcelona, Barcelona, Spain
e-mail: [email protected]
G. Bentley (ed.), European Surgical Orthopaedics and Traumatology,
DOI 10.1007/978-3-642-34746-7_259,# EFORT 2014
4309
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extent of systemic disease is the most easily
understood system of categorizing patient,
regardless of the specialty. We know this
approach by NOMS the capital letters of
N for Neurological status, O for Oncological
factors including tumour histology, M for mechanical stability of spine and finally S for
Systemic evaluation of the overall extent of
disease. These must always be factored in to
decision-making processes.
We advise the use a guideline combining the
Harrington classification (neurological status
and structural changes), Tokuhashi’s prognostic
scoring system and Tomita spread. This is the
modified Harrington classification in five
classes.In this chapter we discuss the role of con-
ventional and stereotactic radiotherapy treat-
ment and the different approach and
management according to the site of the lesion
in the cervical or thoracolumbar areas.
A more specific question is what is the role
of en bloc surgery for metastatic tumours of
the spine? We do these procedures in patients
suffering from single spinal metastases deriv-
ing from the primary tumour, with a long lifeexpectancy and already treated but we also
need to include tumour size, location and
Wenstein Boriani Biagini (WBB) surgical
score classification in order to know if it’s
possible to do it. Our conclusion is that there
is no significant difference of survival time,
but the local recurrence rate of en bloc resec-
tion is lower than for debulking.
Finally, we describe some specific surgical
procedures in different cases, radiation ther-apy, open surgery with decompression and
instrumentation, en bloc resection and the cur-
rent role of percutaneous image-guided verte-
bral body augmentation.
Keywords
Aetiology and Classification Biomechanics
and pathology Diagnosis Surgical
indications Surgical Technique
Vertebrectomy and Kyphoplasty
Decom-pression and instrumentation Complications
General Introduction
Cancer is the leading cause of death in western
world having supplanted heart disease in those
under age 85 since 1999 [1]. Recent data suggesta progressively improving trend in survival.
Since 1993, the death rate from all cancers com-
bined has decreased by 1.5 % per year among
men, and by 0.8 % among women. Mortality
rates continue to decrease for the three most
common sites in men (lung, colorectal, and pros-
tate) and in women for breast and colorectal
cancer [2 – 4].
Metastatic disease to the spine is by far the
most common clinical problem confrontingspine oncologists. Some autopsy data suggest
that metastases to the spine are present in more
than 70 % of the patients with the most common
cancers (breast, lung, and prostate), these data,
comes from original article by Jaffe [5] but
could be exaggerated. Other autopsy studies
have been performed to evaluate the rate of
spinal metastasis SM. Spines from 832
deceased patients with diagnosis of malignant
neoplasm were studied grossly, microscopi-cally, and radiographically by Wong et al. [6].
Overall metastases were disclosed in 36 % of
patients dying of neoplastic disease. Around
16 % were occult and not visible on plains
radiographies. The actual clinical incidence of
symptomatic epidural metastases causing spinal
cord and cauda equina compression is perhaps
much lower (around 5 %) [7].
Technological advances during the last two
decades have greatly expanded the possibilitiesfor treatment in oncology; this progress has
resulted in newer tools for diagnosis, treatment,
and follow-up.
The treatment of metastatic spine disease has
evolved significantly with the introduction of
advanced interventional, surgical and radiation
techniques. Successful treatment of SM
accomplishes effective pain palliation, mainte-
nance or recovery of neurological function and
ambulation, local durable pain control, spinalstability, and improved quality of life.
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Multiple guideline-scoring system have been
describe last two decades but the definitive
evidence-based-medicine has not yet been
determined.
Aetiology and Classification
The prevalence of primary tumours varies
according to published reports. Kostuick [8] in
a summary of 2,748 cases considering only solid
tumours, breast, lung and prostate compose the
majority of SM, followed by renal, gastrointesti-
nal and thyroid carcinomas. In the autopsy stud-
ies, breast and lung accounted for the most
frequent primary sites, followed bylymphoreticular malignancies, and pancreas.
Some SM may occur with no known history of
a primary site- Klimo [9] estimates 10 % of
metastases ignores the aetiology. The more his-
tological disclosed primary tumours are lung,
followed by prostate and kidney [10].
Besides the aetiology, the SM could be classi-
fied according to, their localization, the bony
pattern (lytic or sclerotic or a combination of
both) and the neurological signs. Several preoper-ative scoring systems have been proposed to clas-
sify patients with SM, to obtain prognostic
evaluation and designed a correspondent treatment.
Karnosky [11] score, is a functional to assess
the general condition of the patient with meta-
static disease, and could be used evaluating the
postoperative result of the surgical treatment. It’s
a subjective score with 100 points for abnormal,
healthy status to 0 for dead or 10: fatal processes,
progressing rapidly; moribund.Tokuhasi [12] proposed in 1990 a system to
assess the prognosis of metastatic spine tumours
using six parameters (Table 1) and in 2005
revised his system, increasing the role of the
primary site of cancer, with improvement in
prognosis prediction from 63 % to 82 %.
Tomita [13] proposed in 2001 a three prog-
nostic factor score for SM (Table 2) Finally more
in relation with neurological status the SM could
be classified in five categories followingHarrintong [14] classification score (Table 3).
Applied Biomechanics, Pathologyand Basic Science
Metastatic Tumour Cells
Although the genetic basis of tumours are varied,
the steps or stages in the development and rele-
vant clinical metastases are very similar for all
tumours. Because the tumour cells metastasize,
the malignant cells that have primary access tothe vascular system and travel through the
Table 1 Tokuhasi score. Tokuhasi [12] proposed in 1990a system to assess the prognosis of metastatic spine
tumours using six parameters and in 2005 revised his
system, increasing the role of the primary site of cancer
Characteristic Score
General condition (performance status)Poor (PS 10–40 %) 0
Moderate (PS 50–70 %) 1
Good (PS 90–100 %) 2
No. of extra spinal bone metastases foci
3 0
1–2 1
0 2
No. of metastases in the vertebral body
3 0
2 1
1 2Metastases to the major internal organs
Unremovable 0
Removable 1
No metastases 2
Primary site of the cancer
Lung, osteosarcoma, stomach, bladder,
esophagus, pancreas
0
Liver, gallbladder, unidentified 1
Others 2
Kidney, uterus 3
Rectum 4
Thyroid, breast, prostate, carcinoid tumour 5
Palsy
Complete (Frankel A, B) 0
Incomplete (Frankel C, D) 1
None (Frankel E) 2
Criteria of predicted prognosis: Total Score (TS)
0–8 ¼ >6 month; TS 9–11 ¼ 6 month; TS
12–15 ¼ 1 year
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circulation to the bone marrow and grow within
the bone. Thus the tumour cells are able to per-
form a number of basic activities and to induce
reproducible angiogenesis, invasion of soft tissue
and bone turnover.
Angiogenesis
Tumours developed in two phases and vascular
pre-vascular. The first can exist for months and
years and is characterized by limited growth and
little or no metastasis. The vascular phase, on the
contrary is characterized by rapid growth and
metastasis microscopic bleeding. To enter thestream vascular tumours should develop vessel
formation at the site of the primary tumour. In
the absence of angiogenesis localized tumour
masses do not reach a diameter greater than
2 mm (106 cells). After the formation of the
vascular access to tumours, the tumour cells
get into the bloodstream and allow the release
of growth factors and matrix proteins of the
tumour. These are produced in the endothelium
of new capillaries and are responsible for pro-ducing a paracrine invasion and the growth of
tumour cells (Fig. 1).
The importance of angiogenesis in the
metastatic process is very clear, and corroborated
by the fact that some cancers have an inverserelationship with vascularity and patient survival.
This is especially true for prostate cancer
Table 2 Tomita score. Tomita [13] proposed in 2001 a three prognostic factor score for SM (Table 3)
Scoring system
Prognostic factors
Point Primarytumor
VIsceralmets.
Bonemets.
Slowgrowth
[Breast,thyroid, etc]
[Kidney,uterus etc]
[Lung,stomach, etc]
Solitaryor
isolated
Moderategrowth
rapidgrowth
un-treatable
treatableMultible
Prognosticscore
4
2
1
2
3
4
5
6
7
8
9
10
Treatmentgoal
Surgicalstrategy
Long-termlocal control
Middle-termlocal control
Short-termPalliation
Terminalcare
Supportivecare
Palliativesurgery
Marginal orintralesional
excision
Wide or Marginalexcision***
Table 3 Harrington Spinal Metastases categories in rela-tion with neurological status the SM could be classified in
five categories following Harrintong [14] classification
score. Harrington classification based on structural defect
and neurological deficit
Class
Neulogical
status Structural changes
I Not
significant
No vertebral collapse
II Not
significant
Vertebral involvement
without collapse or instability
(lytic or blastic lesion)
II Major
(sensory or
motor)
No significant bone
destruction or instability
IV Not
significant
Mechanical pain from
vertebralcollapse ¼ or – Instability
V Major Retropulsion of hard
discovertebral
elements ¼ or – Kyphotic
deformity
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and breast, so these vascular tumours have
a higher probability of developing distant metas-
tases than those with a low level of
vascularisation.
Invasion of Soft Tissue
At the end of the process there is metastatic
invasion of the stroma and the basement
membrane. This process of invasion of soft
tissues has three phases: link, matrix destruction
and migration. The invasion by cancer cells
occurs with the binding of extracellular matrixcomponents, secreting enzymes degrading the
matrix and moving through the tissue. Without
these processes the cancer cells cannot enter the
adjacent vessels or nodes, and as a result
are not able to travel to distant organs such as
the lungs or bone (Fig. 2).
Bone Resorption
The invasion of tumour cells at the site of skel-
etal metastases is very different from the
invasion which occurs in the primary tumour.
To invade bone, the tumour cells must penetrate
the connective tissue mineralization. The
destruction of the mineralized portion of the
bone is a passive process that requires a low
pH and the destruction of the portion of bonecollagen is an active process that requires
the action of enzymes-collagenases. Unlike the
Fig. 1 Tumour angiogenesis and neovasculature. Toenter the stream vascular tumours should develop vessel
formation at the site of the primary tumour. In the absence
of angiogenesis localized tumour masses do not reach
a diameter greater than 2 mm (106 cells)
Fig. 2 Invasion of soft tissue. This process of invasion of soft tissues has three phases: link, matrix destruction and
migration
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destruction that occurs in tumour cells of soft
tissue is the direct activity of the cells them-
selves, resorption of bone metastases occurs
with the activation of osteoclasts. Osteoclasts
destroy cells as fraction of mineralized bone
like (Fig. 3).
Eighty-five percent of metastatic spinal
lesions are located in the vertebral body, being
intramedullary. Other locations are epidural,paravertebral and foraminal. In patients with
spinal metastasis, pathological fracture can
occur under normal physiological stress. Partial
or total destruction of the anterior vertebral body
results in decreased load-bearing capacity of the
spine. How and when pathological fracture
occurs is generally determined by the size and
location of the tumour, the extent of tumour
destruction, and the patient’s bone mineral
attenuation [14]. The threshold for pathologicalfracture can be accurately predicted by
evaluating the relationship between bone mineral
attenuation and the cross-sectional area of the
intact vertebral body [15].
Mechanism of Spinal CordCompression
The spinal cord injury secondary to metastatic
process is estimated at 8.5 per 100,000, some-
what higher than traumatic spinal cord injury.
The outcome of it is directly related to the nature
of the disease. There are several reasons
responsible for spinal cord injury: direct com-
pression expansion tumour or retropulsion
a bone fragment in pathological fractures,kyphotic deformity which collapses the body
and intradural metastatic lesion without evidence
of a bone lesion. In all these situations this is due
to through an alteration of vascularity there
develops a state of irreversible nervous tissue
ischaemia. It may be important to take surgical
action quickly at the first signs of spinal cord
compression.
Diagnosis
Symptoms-general: we need a complete medical
history by about weight loss, anorexia, fatigue
and changes in bowel habits and urinals.
Spine pain is the most common presentation,
about 85 % of patients. The pain is usually insid-
ious at first and tends to be progressive. When
there is pain pathological fracture may have an
acute presentation. The location may be cervical,thoracic, lumbar or lumbosacral. The cause of the
pain is from vertebral body cortical expansion
and invasion of soft tissues. The pain is usually
worse with standing and walking and does not
yield to rest, even waking the patient at night. By
itself is not a mechanical pain, but it affects the
stability of the spine [16].
Radicular pain: indicates compression or inva-
sion of the root growth of the tumour or patho-
logical fracture. This pain radiated does notrespond to rest and is difficult to respond to
Fig. 3 Bone resorption. The destruction of the mineral-ized portion of the bone is a passive process that requires
a low pH and the destruction of the portion of bone
collagen is an active process that requires the action of
enzymes collagenases. Osteoclasts destroy cells
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treatment. Muscle weakness is present in 70 % of
patients with metastases as a first symptom, but
we know how to differentiate between neurolog-
ical deficit and weakness secondary to systemic
disease.
Physical examination: assess cachexia or skinlesions and spinal deformity caused by muscle
contraction or by vertebral collapse. Selective
spinal palpation looking for points of pain. Discard
the existence of lymphadenopathy. The full neuro-
logical assessment should include: exploring sen-
sory, and motor reflexes in all four extremities.
Sensory level-look at chest and abdomen; assess-
ment of medullary cone with examining the func-
tion of sphincters.
Radiology: We usually we ask projections lat-eral and AP alignment to assess vertebral bone
and soft tissue integrity. But keep in mind that
radiology image shows no pathological involve-
ment until reaching between 30 % and 50 % of
trabecular bone loss. Once we see the radiologi-
cal injury we should study the location of
vertebrae, the pedicle appearances (“winking
owl” in AP), the radiological pattern (lytic,
blastic or mixed), the existence of deformity
(kyphosis, subluxation) and the existence of path-ological fracture.
The radiological evidence of tumour depends
on the type of tumour and is seen in 94 % of breast
tumours, 74 % of lung tumours and 40 % of
lymphomas and in 85 % of neoplastic spinal
cord compression. A normal radiograph does
not exclude metastatic involvement.
Bone scintigraphy: shows the existence of
osteoblastic activity throughout the skeleton
tracking and representing an important tool inscreening for vertebral neoplasia. In the case of
multiple involvement it helps us to choose the
most suitable site to perform a biopsy. It is
much more sensitive than radiography for it
gives earlier diagnosis, but is not
specific. However scintigraphy together with lab-
oratory and physical examination can identify up
to 95 % of metastatic lesions.
CT: This gives us the best picture of bone
involvement and the degree of bone destruction.It plays an important role in surgical planning in
the case. With the help of intrathecal contrast one
can better delimit the nerve structures in cases
where it is not possible to perform MRI.
MRI: The examination of choice to define
metastatic spinal disease. It is a non-invasive
technique that gives images in several planesand not just the injury but an anatomical region.
You can evaluate the bone marrow, meninges and
paravertebral space. It has high sensitivity to
reflect changes in the bone marrow, leading us
to overestimate sometimes the picture. MRI
allows us to distinguish between infection that
affects the spinal disc space from the metastatic
lesion that affects the intervertebral disc.
Angiography: is indicated for: (1) pre-operative
embolization of highly vascularised tumours,(2) location of the vascularity of the lesion, and
(3) identification of the artery of Adamkiewicz or
neural vascularisation of the area.
PET
Finally, positron emission tomography (PET)
employs tagged molecules to detect regions of
increased uptake. F-fluoride detects regions of increased fluoride uptake and thereby serves as
a marker of skeletal re-modelling. Fluorodeox-
yglucose (FDG) aggregates in regions of
increased metabolic activity in the skeleton and
soft tissues and signals regions of neoplastic,
inflammatory, or infectious activity. Both
F-PET and FDGPET scans have been shown to
be useful in staging systemic disease in cancer
patients in combination with CT and MRI. All of
the nuclear modalities provide better definition of lytic and mixed lesions in comparison to sclerotic
lesions. This is likely related to the acellular and
thereby hypometabolic nature of sclerotic
lesions.
Biopsy: percutaneous vertebral biopsy can be
performed and it is indicated to confirm metastatic
disease in a patient with a known primary tumour,
to evaluate a suspicious radiographic lesion, or to
provide tissue for hormonal evaluation.
Percutaneous biopsy is better performed usinga large biopsy needle in order to obtain
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a sufficient amount of tissue. The biopsy can be
performed under image intensifier control but CTguidance is preferable because of the more accu-
rate spatial resolution (Figs. 4 and 5).
The accuracy rate for percutaneous bone
biopsies is reported to be 90 % in diagnosingmetastatic lesions and the complication rate is
as low as 0.2 % [17].
Fig. 4 Vertebroplasty of a matestasisc lesion in the lumbar area
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Fig. 5 Posterior decompression and instrumentation in acute metastasis with epidural metastases mass
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Treatment of Spinal Metastases andIndications for Surgery
Spinal metastasis treatment needs a multidis-
ciplinary approach. Depending on the primarylesion, the degree of osseous destruction and
neurological compromise, as well as patient
co-morbidity and expectations, the treatment of
metastatic spinal lesions needs to be
individualized.
Different possible modalities include, non-
surgical measures, with pain management and
use of bisphosphonates to minimize risk of oste-
oclastic destruction of bone, chemotherapy, radi-
ation therapy and surgery.
Steroids
The use of glucocorticoids [18] in the treat-
ment of metastasis with neurological thought
to be due to oedema probably has an effect. Of
all these, dexamethasone is most recommended
for its minimal effect on the retention of salt
and the relative potency over other corticoste-roids. Two types have been recommended-low
dosage (4 mg every 6 h) or high (100mgrs
initial ev, and 24 mgrs oral every 6 h for
4 days). There are however serious potential
complications of therapy with steroids, which
include psychosis, diabetes, increased suscep-
tibility to infections and gastro-intestinal
bleeding.
Chemotherapy
Krakoff [19] defines three types of tumoral
sensitivity to chemotherapy (8):
Highly sensitive: Childhood cancers (like acute
lymphocytic leukaemia, Wilms tumour,
Ewing’s tumour, retinoblastoma, and rhabdo-
myosarcoma). Hodgkin’s lymphoma, Carci-
noma of the testis, Choriocarcinoma,
Burkitt’s tumour or Acute promyelocytic leu-kemia. In many centres chemotherapy is con-
sidered the primary treatment for patients with
these tumours even in the presence of epidural
compression.
Moderately sensitive: Adenocarcinoma of breast,
Non-Hodgkin’s lymphoma, Lung cancer,
Osteosarcoma, Adult myeloid and lympho-
cytic leukemia, Carcinoma of the prostate,Colorectal carcinoma, Female cancers of the
ovary, endometrium, and cervix.
Minimally sensitive: Endocrine gland cancers,
Malignant melanoma, Hepatocellular carci-
noma, Renal carcinoma, Pancreatic
carcinoma.
Radiation Therapy
Can be used for treatment of bone pain or neuro-
logical deficits in the absence of mechanical com-
promise. In the last years some advances in
imaging technology and computerized treatment
planning have allowed the safe delivery of high-
dose radiation (spinal radiosurgery) and local
control pass to figures around 70–90 %
depending the histology of the tumour [20].
Conventional RadiotherapyStrong recommendation with moderate- quality
evidence that conventional fractionated RT is an
appropriated initial therapy option in SM with no
relative contra-indications (spinal instability,
prior irradiation, radio-resistant histology and
high-grade spinal cord compression).
Radiosurgery
Strong recommendation with low-quality evi-
dence that radiosurgery should be consideredover RT for SM in the setting of oligometastatic
disease and/or radio-resistant histology with no
relative contra-indication.
Surgical Management
Surgical treatment of vertebral metastases is
a real challenge for a spine surgeon. There are
many strategies currently available for thisdisease, starting with observation to aggressive
en bloc spondylectomy. Furthermore, it is not
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enough to assess the patient only from the
surgical point of view, it is mandatory to assess
the stage of his cancer, needing a multidis-
ciplinary team. Patients with spinal metastases
are often compromised and at higher risk for
surgical and medical complications after aggres-sive treatment.
A prospective randomized clinical trial
conducted by Patchell et al. [21] provides fairly
convincing support for the role of surgery in the
treatment of patients with spinal cord compression
secondary to metastatic solid tumours. The multi-
institutional trial included patients with a tissue-
proven diagnosis of cancer with a single metastatic
spinal tumour causing displacement of the spinal
cord and at least a single neurological sign or symptom, which included pain.
The protocol randomized patients into two arms
in a non-blinded fashion. All patients received
high-dose dexamethasone at the time of randomi-
zation. The radiation group underwent 30 Gy in
10 fractions. Patients in the surgical group
underwent an operation, with the goal of achieving
circumferential decompression, and went on to
receive the 30-Gy radiation treatment within
14 days of the operation. The investigators termi-nated the trial after interim data analysis demon-
strated clear superiority of the surgical group in the
primary end-point of the study, which was the
ability to walk after treatment. Patients with spinal
metastases may undergo a wide range of surgical
interventions, ranging from limited decompression
to radical tumour excision.
Indications and Contra-Indications
Surgery is indicated in patients with rapidly
progressing or far-advanced paraplegia, histologi-
cal diagnosis in an unknown primary spinal insta-
bility and/or pathological fracture–dislocation,
failure of radiotherapy/known radio-resistant
lesion Relative contra-indications to surgery are
longstanding complete paralysis (less 24 h) highly
radiosensitive tumour (lymphoma, myeloma)
multiple levels of involvement, poor life expec-tancy (less 3 month) and extreme medical
co-morbidity.
Operative Technique
All patients with mechanical instability require
a spinal stabilization procedure because radiation
therapy and chemotherapy do not restore spinalstability. Depending on the degree of instability
and tumour infiltration, instrumented stabiliza-
tion or vertebroplasty can be performed. Finally
some hard selection cases could be treated with
en bloc resection.
Vertebroplasty and Kyphoplasty
Kyphoplasty or vertebroplasty provides fairlydurable and consistent pain relief for patients
with tumours that infiltrate only the vertebral
body, without significant involvement of the pos-
terior elements and an epidural tumour burden. If
the tumour infiltrates the posterior elements or
significantly extends into the spinal canal, an
instrumented stabilization is generally required
to restore stability and provide adequate pain
relief (Fig. 4).
A review of 97 cement augmentationprocedures performed in 56 patients with various
metastatic spinal tumours revealed that
improvement or complete pain relief was
achieved in 84 % of the procedures [22]. Further-
more, these procedures may be effectively
conducted in conjunction with spinal stereo-
tactic radiosurgery to treat or prevent patholo-
gical compression fractures [23]. The most
common complications of cement injection are
extravasation into the venous plexus or theepidural space and embolization via the vascular
system.
Decompression and Instrumentation
After to reviewing the evidence-based
medicine literature we strong recommend
management of patients with high-
grade spinal cord compression secondary tosolid SM by decompressive surgery and
instrumentation.
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Depending on the location of the tumour and
the goal of the operation, an anterior, posterior,
or lateral approach, or a combination may be
used. The posterior approach to the spine allows
direct access to the spinal cord, obviating the
extensive bone resection generally requiredwith anterior approaches. Furthermore, T3
through T12 nerve roots may generally be
sacrificed without significant morbidity, facilitat-
ing transpedicular access to the ventral elements
of the vertebral column. Most spine surgeons
have greater familiarity with the posterior
approach to the spine, and thus the posterior
approach represents the most commonly used
route for spinal decompression and stabilization
(Fig. 5).
The surgical approach could be influenced by
location.
In the thoracolumbar area we reviewed in
detail 32 of 161 articles with different degreesof evidence.
• The choice of approach was selected largely
based on tumour topography in relation to the
anatomical parts of the vertebra involved.
• The outcomes for either of these approaches
were similar.
• Posterior approach had a higher rate of wound
problems.
Fig. 6 (continued)
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• More wound healing problems with previous
radiation.
Our personal advice is:T2 through T5: strong recommendation for
a posterolateral approach
T6 through L5: strong recommendation for use of
any of the three procedures (Ant, Post, Com-
bined) depending on the clinical presentation,surgeon and patient preference. In lumbar
level sacrifice of nerve roots carries greater
Fig. 6 En bloc resection in an isolated breast metastases
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morbidity, and cardiopulmonary status may
precluded anterior approach.
Cervical location:
Occipital to C2 by posterior approach
C3-C6 by anterior approach
And cervicothoracic area by posterior approach.
En Bloc Resection
The main question is: Which is the role of en bloc
surgery for metastatic tumours of the spine?
Theoretical evidenc for en bloc resection but
there is a paucity of published experience in SM
treatment and the majority of these articles are
about renal cell carcinoma (Fig. 6). This isa comparative table between debulking and en
bloc resection of solitary SM We conclude and
we follow this procedure in patients suffering
from single spinal metastasis deriving from
the primary tumour, with a long life expectancy
and already treated, but we also need to include:
tumour size, location, WWB surgical score
classification in order to know if it’s possible
to do it.
Complications
The rate of complications from surgical proce-
dures on tumour affected vertebral bodies is
high. The majority of the patients are old-aged
and their general condition is reduced.
Hence particularly the mobility after surgery
of these patients is limited. Pulmonarycomplications, thrombosis and decubitus are
frequent consequences. Steroid therapy and/or
radiotherapy often is/are the reason(s)
for wound healing disorders. Patients with
very vascular tumour metastases (renal
cell carcinoma, plasmocytoma) in many cases
suffer from intra-operative complications and
post-operative hematomas. Researching the
literature, the overall rate of complications
from surgical procedures on a tumour af- fectedspine with metastases is high.
Summary
The spine is the most common site of skeletal
metastases. The evolution of surgical methods,
medical treatment, and radiation therapy has ledto improved survival, functional status, and
quality of life for patients with cancer. The role
of surgery in the treatment of patients with spinal
metastases has evolved over time.
The treatment goals of spinal metastases
include the preservation and restoration of
neurological function and spinal stability. Mod-
ern imaging modalities provide accurate methods
of tumour diagnosis. A variety of approaches and
stabilization techniques are available and shouldbe tailored to the location of the tumour and
systemic co-morbidities.
As part of multidisciplinary treatment that
includes radiation therapy and chemotherapy,
surgery provides an effective method of
restoration and preservation of neurological
function and spinal stability for patients with
metastatic spinal tumours.
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