Download Mammoscintigraphy

Breast Cancer and the Role of
Nuclear Medicine
Mark H. Crosthwaite, CNMT, M.Ed.
Associate Professor
Nuclear Medicine Technology
Department of Radiation
Breast cancer statistics for 1998 from
American Cancer Society estimate more
than 182,000 new cases of breast cancer
will be diagnosed during the year
For women between the ages of 35-54 it is
the leading cause of death
1 out of every 9 women will be diagnosed
with this disease
Early diagnosis
Early treatment
Reduced mortality
Two methods of screening for
disease:
• Self examination and physical
examination
• Mammography
•Mammography
• Has a sensitivity between 15 to 20%
• Is less helpful with women who have:
- Extremely dense breasts
- Heterogeneously dense breasts
- Surgically scarred breasts
- Post radiation therapy fibrosis
- Diffuse distribution of indistinct
calcifications
- Breast implants
Does nuclear medicine have a
role in this?
- Physiology vs. anatomy
- What types of radiopharmaceuticals might be
available?
• Tl-201 and tumor uptake
- Blood flow
- ATPase sodium potassium
pump
• Calcium ion channel
• Leakage of immature tumor
cells
• Reduced or no uptake in
connective tissue containing
inflammatory cells and necrotic
tissue
Tc99m sestamibi (Miraluma)
tumor uptake
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-
First reported by in Campeau
et al in 1992 (see references)
Uptake in tumor is a result of
blood flow, mitochondria
negative charge and density with
tracer being positively charged
F18-FDG
- Tumor has a great affinity for
glucose
- FDG is a glucose analog
- Tumor to background is 3:1
Sestamibi clinical trials
- For palpable mass
-
78% sensitivity
82% specificity
- Non-Palpable mass
- 40 – 50% sensitivity
- 90 – 95% specificity
Non-palpable tumor and
relation to size
- Less than 1 cm the
sensitivity was 20 – 30%
- Greater than 1 cm the
sensitivity was 60 – 70%
Tofani, et al evaluated 300
breast cancer patients tumor
size <1cm had a sensitivity of
48% and tumor > 1 cm had a
sensitivity of 95% (see
references)
Clinical role of scintimammography
according to Dupont Pharma (see
references)
- Not to be used in screening or to
replace biopsy
- According to Dupont Pharma,
“Miraluma as a second line diagnostic
drug after mammography to assist in
the evaluation of breast lesions in
patients with an abnormal
mammogram or a palpable breast
mass.”
It is specifically suggested for:
- Palpable mass not seen on mammography
- Increased size of mass on mammography
- Change in contour of mass seen on
mammography
- Mass seen on mammography, but not on
ultrasound
- Mass developing in area of scar or previous
surgical site
- Increased number of previously
demonstrated calcifications
- Multifocal areas of clustered calcifications
- Calcifications at surgical site
Procedure
- Equipment setup
- Small field of view camera
-
-
with a LEHR collimator
Energy - 140 keV with a 10%
window
Matrix – 128 x 128
Acquisition time 600 seconds per
view
Table overlay/matrix that has
cutouts for breasts to be imaged
in a prone dependent-breast
position
Radiopharmaceutical administration
- 25 mCi of Tc99m sestamibi
- Inject IV into the contralateral arm of the
suspected lesion
- If bilateral disease is suspected the
radiopharmaceutical should be injected
into a leg vein
Imaging
- Start imaging 5 minutes post
injection
- Patient should initially be in the
prone position with the breasts
inserted through the cutouts, in the
“dependent-breast” position.
- Breast should not be pinched at the
base and note the angle of the
nipple
- Lateral views of both breast
should be taken
- From the supine position
have the patient place her
arms behind her head and
take an anterior view that
would include both breasts
and lymph nodes in the axillae
SPECT is not necessary
recommended because of the
amount of activity coming from
the heart and GI tract
Negative For Breast Cancer
Breast Cancer Detected
Scinti-Camera Technology
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•
•
•
Current Auger cameras technology is a limiting factor in
Reduced resolution
Bulky size of detector has difficulty in positioning
Need for smaller and more versatile detector
SPEM
•
•
•
•
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Single-Photon Emission Mammography
Concept - Compact scintillation camera uses an array of
discrete scintillator Crystals
Matching array of photodiodes replaces PMTs and
detects the scintillation light that results when a gamma
ray is absorbed.
Digital imaging where CsI(Tl) replaces NaI(Tl)
Reduced camera/detector size
Improved spatial resolution
Compact size allows for closer and varied angles
Less expensive system
Literature Results on SPEM
• SPEM was compared with a large field of
view camera using Tc99m-sestamibi
• The small size of the detector head allows
the use of mechanical breast compression to
minimize detection distance and tissue
scatter
• Found a 0.4 cm breast lesion that was
missed on an Anger Camera
Still On the Drawing Board
• Small digital camera on a flexible arm
• Improves resolution
• Reduces background
Still On The Drawing Board
• This system has four digital imaging plates
This movable plates can be adjusted
• Assume that there might also be some
breast compression
• Better resolution and reduced background
Use of F18-FDG
• In comparison with Tc99m-sestamibi
• Mixed results
• Is F18-FDG the radionuclide of choice for
the detection of breast cancer?
• However, the technology for imaging breast
cancer also changed with the application of
a specialized PET system
Current Technology – PEM
Positron Emission
Mammography
• Dilon Technology is on the
left. They refer to their
system and its technology as
Molecular Breast Imaging
(MBI)
• GE has also made a system
which is displayed on the
right and refers to the
imaging as breast-specific
gamma imaging (BSGI)
Dilon - BMI
• System employs breast
compression along with
the detection of
coincidence detection of
511 keV photons
• This is an example where
mammography picked up
a calcification which
turned out to be cancerous
• BMI identified two
cancerous lesions which
where verified by biopsy
and MRI
• Can resolve to 3 mm
• Sensitivity – 90%
• Specificity – 85
• Axillary node issue
Another Case from BMI Files
• Mammography
identifies very dense
breast tissue. Difficult
to any specific breast
mass
• MBI identified a mass
which via biopsy is
proven to be cancerous
• For more information
visit
http://www.dilon.com/
Can F-18FDG be useful in
detecting/staging breast cancer?
Scheidhauer et al - The
accuracy of PET in the
detection of primary breast
cancer was 90%, and in the
detection of involved axillary
lymph nodes is 94%
Utech et al, stated, “In patients
with breast carcinoma, 18F-FDG
PET can be of value in
evaluating axillary lymph nodes
for metastatic involvement prior
to surgery.”
In an article entitled, “Comparison of
FDG-PET with MIBI-SPECT in the
detection of breast cancer and
axillary lymph node metastasis” it
studied and compared FDG-PET to
MIBI-SPECT. The authors
concluded “Neither FDG-PET nor
MIBI-SPECT is sufficiently sensitive
to rule out axillary lymph node
metastasis.
Regarding the use of chemotherapy
and the role of FDG. Bassa and
colleagues concluded, “FDG-PET is
valuable for monitoring the effects of
preoperative chemotherapy in patients
with locally advanced breast cancer
with better sensitivity for primary
tumor and better specificity for nodal
metastasis in comparison with
ultrasonography.”
FDG’s Future in Breast Imaging
• While not cancer specific FDG is
incorporated into breast cancers because of
it needs for glucose
• Its used to diagnose evaluate primary tumor,
assess staging/restaging, and monitor
response to therapy
• Newer PET systems can resolve tumors to
≤4 mm.
• Imaging difficulty occurs with lactation and
mastitis
Other PET Agents
• Flouro-L-thymidine (FLT)
– Detects high levels of DNM synthesis
– Not considered for routine staging, however, it
may have a role in predicting the course of
therapy (future)
• Flouro-17-β-estradio. (FES)
– Is an estrogen receptor and may have a future
role in immunohistochemical response to
different tumor types
– And there are others. See – Molecular Imaging
of Breast Cancer by M, THO, et al
- Conclusion
- Has the role of mammoscintigraphy been clearly
defined?
- Where do we go from here?
References
• Miraluma: Kit for the Preparation of Technetium Tc 99m Sestamibi. (Version 2.0) (CD-ROM).
(1997). Billerica, MA: Dupont Merck Pharmaceutical Company.
• Iraniha S, Khalkhali I, et al. Breast cancer imaging: can Tc-99m Sestamibi
Scintimammography fit in? Medscape Womane’s Health. 1997 2(4)
• http://www.medscape.com/medscape/WomensHealth/journal/1997/v02.n04/w3182.khalkhali/w
3182.khalkhali.html
• Bassa P, Kim EE, Inoue et al. Evaluation of preoperative chemotherapy using PET with
fluorine-18-fluorodeoxyglucose in breast cancer. Journal of Nuclear Medicine. 1996:
37(6):931-8.
• Campeau RJ. Kronemer KA. Sutherland CM. Concordant uptake of Tc-99m sestamibi and Tl201 in unsuspected breast tumor. Clinical Nuclear Medicine. 1992: 17(12):936-7.
• Yutani K, Shiba E, et al. Comparison of FDG-PET with MIBI-SPECT in the detection of
breast cancer and axillary lymph node metastasis. Journal of Computer Assisted Tomography.
2000: 24(2):274-80.
• Tofani A, Sciuto R, et al. 99Tcm-MIBI scintimammography in 300 consecutive patients:
factors that may affect accuracy. Nuclear Medicine Communications. 1999 20(12):1113-21.
• Scheidhauer K, Scharl A, et al. Qualitative [18F]FDG positron emission tomography in
primary breast cancer: clinical relevance and practicability. European Journal of Nuclear
Medicine. 1996: 23(6):618-23.
• Utech CI. Young CS. Winter PF. Prospective evaluation of fluorine-18 fluorodeoxyglucose
positron emission tomography in breast cancer for staging of the axilla related to surgery and
immunocytochemistry. European Journal of Nuclear Medicine. 1996: 23(12):1588-93.
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