CLINICAL USE OF SPECT-CT IN BREAST & PROSTATE CANCERS
Emerita A. Barrenechea, MD Department of Nuclear Medicine St Lukes
Medical Center St Lukes Medical Center & Veterans Memorial
Medical Center Philippines Slide 2 Introduction SPECT-CT: emerging
dual-modality imaging technique with many established and potential
clinical applications in the field of oncology. As with PET-CT,
accurate co-registration of anatomical and functional data from
combined SPECT-CT camera often provides complementary diagnostic
information. Collection of both sets of imaging data in the same
exam increases the likelihood of 1:1 mapping and improved
diagnostic accuracy. Slide 3 Slide 4 SPECT Radiopharmaceuticals
More specific More specific Longer half-lives allowing for delayed
or increased imaging Longer half-lives allowing for delayed or
increased imaging Like PET, extremely useful in determining organ
or tissue function, which is augmented with anatomical correlation
with CT scanning Like PET, extremely useful in determining organ or
tissue function, which is augmented with anatomical correlation
with CT scanning Slide 5 SPECT-CT guided Bone Scintigraphy Bone
scintigraphy is often used to detect possible areas of metastases,
but the scans are so nonspecific that further radiological
follow-up is always needed when abnormal uptake is present. Using
the hybrid scanner, a patient undergoes SPECT imaging alone; if
abnormality is detected, the patient remains on the table for a
focused CT scan of the suspect region. Bone scintigraphy is often
used to detect possible areas of metastases, but the scans are so
nonspecific that further radiological follow-up is always needed
when abnormal uptake is present. Using the hybrid scanner, a
patient undergoes SPECT imaging alone; if abnormality is detected,
the patient remains on the table for a focused CT scan of the
suspect region. Slide 6 Applications: Detection of primary or
metastatic lesions Detection of primary or metastatic lesions
Staging of malignant disease Staging of malignant disease
Assessment of chemotherapy or radionuclide therapy Assessment of
chemotherapy or radionuclide therapy Sentinel node identification
Sentinel node identification Locating difficult lesions in oncology
Locating difficult lesions in oncology Slide 7 Clinical
Applications in Oncology Endocrine tumors Endocrine tumors
Lymphoscintigraphy Lymphoscintigraphy Lung cancer Lung cancer Brain
tumors Brain tumors Bone scan Bone scan Liver perfusion studies
Liver perfusion studies Liver hemangiomas Liver hemangiomas Slide 8
Breast Cancer It is the most prevalent cancer worldwide in women.
It is the most prevalent cancer worldwide in women. PET with FDG
may be the most single sensitive imaging test to detect primary and
systemic metastases but fails to detect microscopic disease smaller
than 5- 10mm lesions as well as limited capabilities in axillary
nodal evaluation where SPECT/CT lymphoscintigraphy is preferred PET
with FDG may be the most single sensitive imaging test to detect
primary and systemic metastases but fails to detect microscopic
disease smaller than 5- 10mm lesions as well as limited
capabilities in axillary nodal evaluation where SPECT/CT
lymphoscintigraphy is preferred Slide 9 Tc 99m Sestamibi
Scintimammography Slide 10 Slide 11 Sentinel Node - Breast Slide 12
Sentinel Node - Melanoma Slide 13 Sentinel Node Mapping Slide 14
Indications on planar lymphoscintigraphy for additional SPECT-CT
Unusual lymphatic drainage patterns Extraaxillary drainage in
breast cancer patients Extraaxillary drainage in breast cancer
patients Drainage to more than one lymph node basin Drainage to
more than one lymph node basin Drainage not to nearest lymph node
basin Drainage not to nearest lymph node basin Slide 15 Indications
(contd) Lymphatic patterns difficult to interpret Sentinel lymph
node close to injection site Sentinel lymph node close to injection
site Deeply located sentinel lymph nodes Deeply located sentinel
lymph nodesNon-visualization No lymphatic drainage on late planar
images No lymphatic drainage on late planar images Slide 16
SPECT-CT Imaging: Breast Cancer A = Anterior B = L Lateral No
lymphatic drainage 4hrs C = Axillary Sentinel Node Slide 17
SPECT-CT Imaging: Breast Cancer No lymphatic drainage Axillary
sentinel node Internal Mammary sentinel node Slide 18 SPECT-CT
Imaging: Breast Cancer Int Mam LN 2 nd Echelon LN Slide 19 SPECT-CT
Imaging: Breast Cancer Axillary LN Int Mam LN SLN Breast Slide 20
Slide 21 Adenosylcobalamin: New radiopharmaceutical under
investigation for use in SPECT-CT New radiopharmaceutical under
investigation for use in SPECT-CT Indium 111 DTP adenosylcobalamin
(Vit B 12 analogue) Indium 111 DTP adenosylcobalamin (Vit B 12
analogue) Action: Vitamin B 12 involved in methylation reactions
important in Krebs cycle, thymidine production required for DNA
synthesis. These processes are increased in metabolically active
tissues like cancers Slide 22 Ductal Breast Carcinoma in 4 Women
using Adenosylcobalamin Slide 23 Prostate Cancer Prostate cancer:
leading form of cancer for men, and leading cause of cancer-related
deaths. Slow growing, but lethal once it has metastasized. Indium
111 Capromab Pendetide (ProstaScint) imaging is indicated for
staging and recurrence detection as well as for metastases.
Interpretation without correlated structural information becomes
challenging as the radiopharm demonstrates non-specific uptake in
the normal vasculature, bowel, bone marrow and prostate gland Slide
24 ProstaScint Agent: Indium 111 ProstaScint Agent: Indium 111
ProstaScint Half-life: 2.8 days Half-life: 2.8 days For assessment
of nodal metastases For assessment of nodal metastases Detection of
occult metastatic disease in post-prostatectomy patients Detection
of occult metastatic disease in post-prostatectomy patients Slide
25 Slide 26 Prostate CA: Widespread Osseous Metastases
Interpretation dependent on pattern of tracer distribution
according to expected physiology or pathophysiology Interpretation
dependent on pattern of tracer distribution according to expected
physiology or pathophysiology Slide 27 Prostate CA with
Degenerative Joint Disease Highly sensitive for metabolic increases
in osteoblastic activity Highly sensitive for metabolic increases
in osteoblastic activity Poorly specific: Poorly specific: also
accumulates in inflammation or areas of hypervascularization Slide
28 SPECT Useful in localizing lesions in complex bony structures
such as the skull, vertebral column, or pelvis Useful in localizing
lesions in complex bony structures such as the skull, vertebral
column, or pelvis Prostate CA with neck pains revealed to be of
degenerative origin Prostate CA with neck pains revealed to be of
degenerative origin Slide 29 SPECT Typical bone scan agents like
Tc-99m MDP or HDP are taken up by osteoblasts in bone formation and
chemoabsorbed in the hydroxyapatite mineral component of the
osseous matrix Typical bone scan agents like Tc-99m MDP or HDP are
taken up by osteoblasts in bone formation and chemoabsorbed in the
hydroxyapatite mineral component of the osseous matrix Even with CT
correlation, however, the characteristics of Tc 99m HDP or MDP
limits the study Even with CT correlation, however, the
characteristics of Tc 99m HDP or MDP limits the study Slide 30
Slide 31 Conclusion SPECT-CT imaging in breast, prostate and other
cancers has been proven effective through SPECT-CT imaging in
breast, prostate and other cancers has been proven effective
through improved specificity and diagnostic confidence helping to
guide conventional management and assess suitability for targeted
therapy. combines anatomic and functional techniques to allow
accurate localization of tumors, increased detection of recurrent
and metastatic disease, and exclusion of physiologic uptake.
SPECT-CT combines anatomic and functional techniques to allow
accurate localization of tumors, increased detection of recurrent
and metastatic disease, and exclusion of physiologic uptake. Slide
32 Conclusion Both functional and morphologic information can be
obtained in a single imaging session. Both functional and
morphologic information can be obtained in a single imaging
session. With SPECT-CT, it is now possible to have the best of both
worlds, providing functional information on lesions within an
adequate anatomic context. With SPECT-CT, it is now possible to
have the best of both worlds, providing functional information on
lesions within an adequate anatomic context. Slide 33 Thank you for
youe attention Thank you for your attention.
