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Vertebral Intracavitary Cement
& Samarium (VICS).
A Novel Approach to treat
Painful Vertebral Metastases
H. Ashamalla, M. Macedon,, E. Cardoso, L. Weng,, B.
Mokhtar, A. Guirguis, N. Panigrahi.
Radiation Oncology and Neurosurgery departments
New York Methodist Hospital, Weill Medical college of
Cornell University, NY.
Background
Each year, more than 100,000 patients in
the U.S. develop bone metastases.
 Bone is the third most common site of
metastatic disease after liver and lung
 Up to 40% of patients presenting with
bone mets. will have spinal/vertebral mets,
90% of whom will develop severe axial
pain

Metastatic Bone Disease
Epidemiology - Etiology
Estimated Number
of Persons Living
with Cancer1
Number of New
Cases in 20041
Incidence of
Bone
Metastases2
Breast
2,184,125 (24%)
217,440 (16%)
65-75%
Prostate
1,838,653 (20%)
230,110 (17%)
65-75%
Bladder
521,945 (6%)
60,240 (4%)
40%
Lung
388,538 (4%)
173,770 (13%)
30-40%
Thyroid
273,642 (3%)
23,600 (2%)
60%
Other
4,013,458 (43%)
705,160 (52%)
Total
9,220,361 (100%)
1,368,030 (100%)
1. SEER Cancer Statistics Review 1975 – 2001, National Cancer Institute
2. Coleman, R.E. Cancer Treatment Reviews. 2001;27:165-176.
Metastatic Bone Disease
Metastasis Sites

Most common sites of
metastasis

Vertebra (69%)
Pelvis (41%)

Femur (25%)

Hip (14%)


Median time from cancer
diagnosis to bone
metastasis is 30 months
Vertebral Compression fractures
(VCF)Metastatic cancer in the bone
causes skeletal complications
every 3 to 4 months.
 17 – 50% of patients with
metastatic breast cancer will
develop VCFs annually.
 Median time to first fracture
among breast cancer patients
(not on bisphosphonate) is 12.8
months.

Metastatic Bone Disease
Treatment Goals
Reduce pain
 Eradicate or reduce tumor when primary
tumors are involved
 Prevent neurologic complications
 Treat pathologic fractures and prevent
recurrent fracture

A) Surgical Treatment

Operative Management
 Vertebral
column reconstruction
 A or P decompression with internal fixation
 Oncology patients are generally poor candidates
for open surgery due to soft bone/tumor mass and
co-morbidities

Minimally Invasive Procedures
 Kyphoplasty
 Vertebroplasty
Balloon Kyphoplasty





Patient placed in lateral decubitus position
Trochar inserted into anterior vertebral body under
fluoroscopic guidence
Curretting performed for tissue sample
Balloon inflated to decompress the fracture and to open up
space for cement injection
Balloon removed and PMMA bone cement injected into
cavity to stabilize the vertebra
Balloon Kyphoplasty
Balloon Kyphoplasty
Shown to significantly reduce pain
associated with VCF in patients with
metastatic bony lesions
 However, this procedure does not address
the neoplastic component of the problem

B) Radiation Treatment for Bony
Metastasis
External radiation
 Radionuclides – systemic administration,
localize to all bony mets

Strontium-90
 Samarium-153

Samarium-153
Created by bombarding Samarium-152
(stable) with neutrons
 Comes from manufacturer complexed to
EDTMP
 Beta particles from Sm-153 travel 3.1mm
in tissue, 1.7mm in bone
 Typically administered at the dose of
1mCi/kg

Samarium-153 (systemic)



When given IV, Sm-153-EDTMP (Quadramet)
has an affinity for bone and will concentrate in
areas of high bone turnover, especially bony
metastasis
Mechanism of relief of bone pain is unknown,
but may be due to suppression of the growth of
the tumor cells from radiation
Major adverse effect of systemic administration
is hematologic toxicity with nadir at 3-4wks:



Leukopenia
Thrombocytopenia
Decr. Hemoglobin
60%
69%
40%
Vertebral Intracavitary Cement
and Samarium {VICS}
Procedure
Materials
Methods
Vertebral Intracavitary Cement
and Samarium {VICS}
A novel approach to bony metastasis
 Employs combination of balloon
kyphoplasty and anti-tumoral activity of
Sm-153 injected directly into the affected
vertebra

Objectives
Study feasibility of intravertebral
administration of Sm-153 with kyphoplasty
 Assess procedure-related morbidities
(specifically hematological) related to
procedure
 Monitor pain relief and durability of
response

Eligibility

Inclusion criteria:





Documented bone mets with intact anterior wall of
vertebra
Recurrent pain or progression of metastases in areas
treated by prior external RT
Acceptable candidate for kyphoplasty
Good performance status, Karnofsky ≥ 60
Exclusion criteria



Epidural soft tissue component
Cord impingement or compression
Inability to undergo anesthesia
IRB approval was obtained
 After signing consent, all patients were
assessed for pre-op pain level.
 Pre-op MRI, CT and/or bone scan,
confirming presence of bony metastasis.

VICS Procedure



Insertion of trochar and balloon as with the
balloon Kyphoplasty approach
Under tight radiation safety measures, Sm-153
in escalating doses(1-4mCi) is co-injected and
mixed with the cement as it is injected into the
cavity of the vertebra using a three way valve.
Equipment, drapes, and room are surveyed
post-operatively. Contaminated needles etc. are
taken to the radioactive lab to allow for safe
decay
Procedure
Serial Samarium nuclear scans were
obtained post-op on days 0, 1, 2, and 4.
 F/U bone scans and MRI’s were obtained
at least 1 month post procedure
 Serial blood counts were also monitored

Patients
33 procedures were performed in 26
patients (18 males and 8 females).
 Seven patients had procedures performed
in two vertebral levels.
 The mean age of the cohort was 64 years
(range 33 to 86).
 The mean pain score prior to treatment
was 8.8/10.

Patients
Type
Primary Cancer Site
1
1
1
1
1
2
12
2
5
Lung
Prostate
Colon
Multiple Myeloma
Urinary Bladder
Ovary
Breast
Stomach
Head & neck
#
%
Lung
12
46
Prostate
5
19
Colon
2
7.5
Multiple Myeloma
2
7.5
Urinary Bladder
1
4
Ovary
1
4
Breast
1
4
Stomach
1
4
Head & neck
1
4
Distribution of Treated Vertebrae

Of the 33 vertebrae treated, 20 were in the lumbar
spine, 12 were in the thoracic spine and 1 was in
the sacral spine.
Thoracic
Lubmar
Sacral
Escalating Doses of Samarium
Dose of samarium
(mCi)
1
Number of Procedures
(Patients)
4(3)
2
7(7)
2.5
6(5)
3
8(5)
4
8(6)
A) Patients’ tolerance:
There was no mortality or procedurerelated complications.
 There was no hematological toxicity, no
significant change in the WBC, Hg and
platelets was seen at one month after the
procedure.
 Estimation of dose contribution to spinal
cord using diagrammatic and inverse
square models was 40 ± 6 cGy.

B) Pain control:
All patients tolerated procedure very well.
 The mean pain score (VAS) improved from
8.5 (±2) prior the procedure to 2.6 (±3.1)
one day after the procedure (p<0.0001).
 The ECOG performance scores only
improved marginally from 2.4 (±1) before
to 2 (±1) after (p=0.035, one-sided test).

C) Accuracy and Feasibility:



Whole body Samarium scans confirmed the
local absorption injected 153Samarium-EDTMP in
the intended vertebra in 32 out of the 33
injections.
One patient did not demonstrate clear
absorption of the 153Samarium-EDTMP in the
site with no evidence of spillage nor there was
systemic absorption.
No appreciable radiation leakage or spillage was
encountered.
Localization of Sm-153 in the injected vertebra persistently shown at 3, 24,
48, and 96 hours of post injection.
3 hrs
24 hrs
48 hrs
96 hrs
C) Accuracy and Feasibility:

Prior to treatment (A
B) low-signal lesion
and hyperintensity
(arrows) in the
anterior aspect of
the vertebral body.

12 months after
procedure (C , D):
local control of the
disease is observed
C) Accuracy and Feasibility:


On the left side there is evidence of targeting at the
injected L2. Decrease in signal from day 1 to day 3 after
treatment is observed.
The decline of radioactivity was consistent with the
known half life of 153Sm and followed the physical in-vitro
decay. On the right side, the curve shows the mean in
vivo decay of 153Sm in 11 patients (± 1SD) as compared
to in vitro decay.
D) Systemic absorption



Variable systemic absorption was evident in
Samarium scans in all patients (9-75%). The
mean ratio between the concentrations of 153Sm
in the target vertebrae and normal tissues was
37±26.3 (ranging from 9.3 to 92.1).
Patients with wide spread bone disease had
demonstrated Samarium absorption in distant
metastatic sites.
Asymptomatic extravasation of
cement/Samarium was encountered in 6
vertebrae (6/33).
Absorbed Sm-153 targets other skeletal lesions: right clavicle,
manubrium, and right posterior ilium. All these lesions were present on
pre-treatment bone scan.
Ant.
Post
Bone scan
Ant.
Post
Samarium scan
D) Cytotoxic effect:
Reduced intensity of bone tracer (99mTcMDP) uptake was studied in 8 patients
 The ratio of mean counts in the intended
vertebra to soft tissue after correction to
background was 12.1 prior to the
procedure dropped down to 6.9 at the last
follow up scan (3-12 months)

D) Cytotoxic Effect

Whole-body bone scans before treatment,
at 8 and 22 months post-treatment. The
new scan reveals reduction of uptake at
the treated vertebra L1, while new area of
uptake appears at L2.
Drawbacks to VICS
Radiation Safety: Open liquid radiation
source.
 Obtaining Sm-153 on a timely basis from
manufacturer
 Unsuitable for open procedures

Conclusions
Vertebral Intracavitary Cement and
Samarium {VICS}
Injection of Sm-153 is feasible and can be
performed safely
 No adverse effects were seen as a result
of the procedure
 No hematologic toxicities were seen
 Indirect evidence for the cytotoxicity of the
procedure is observed through reduction
of the intensity of uptake in bone scan.

Future Directions

Need direct head-to-head comparison of
VICS with balloon Kyphoplasty to
determine if there is any net change in the
duration of response, or in level of pain
relief