Transcript Molecular Imaging “101” - HealthCare Provider | SNMMI

Molecular Imaging “101”
Martin G. Pomper, MD, PhD
Russell H. Morgan Department
of Radiology and Radiological Science
Johns Hopkins University
The Role of Molecular Imaging in Cancer
Briefing and Roundtable
Washington, DC
July 22, 2008
The evolution of diagnostic imaging
PAST
PRESENT
Anatomic
Functional
Hybrid
plain films, CT,
MRI, US
angiography,
doppler US, NM,
MRI, PET
PET/CT,
SPECT/CT, PET/MR
“FUTURE”
Molecular
NM, PET, SPECT,
MRS, optical,
PET/MRI
contrast-enhanced
MRI/US/CT
What is molecular imaging?
“Viewing” the Body’s Biological Processes

Uses imaging technologies to assess biological
activity in the body

Shows what cells are doing and how they are
functioning over time

Different than x-rays or CT scans that show
anatomical pictures of the body’s organs and
tissues

Changes in physiology and biochemistry occur
prior to changes in anatomy
Why is molecular imaging
important?





Enables early detection and/or identification of
changes occurring in tissue
Enables changes in individual patient management
in real time (personalized medicine)
Facilitates drug development
Allows researchers to explore new ways to manage
and treat illnesses
Serves as a noninvasive diagnostic and monitoring
tool
Molecular imaging modalities
Sensitivity
Modality
Agents
H
R
Primary uses
Examples
FMT
fluorescent
proteins
x
X
gene expression, tagging
superficial structures
GFP, RFP, NIRF
probes
BLI
luciferin
X
gene expression, therapeutic
monitoring
fLuc rLuc
X
site-selectivity, protein labeling
99mTc-annex
Optical
pM
Nuclear
SPECT
nM
99mTc, 123/5I, 111In
X
in V, 123I-
A85380
PET
11C, 18F, 124I,
X
X
64/62/60Cu
site-selectivity, gene
expression, drug development
11C-RAC, 124I-FIAU,
64Cu-ATSM
MRI
M
spectroscopy
endogenous
metabolites
X
X
CNS, prostate , heart , breast
NAA, Cr, Cho, Glx, mI,
31P
contrast
agents
Gd, Mn, FeO
x
X
cell trafficking, enzymatic
activation
poly-L-lysine,
dendrimers, MION
X
drug-delivery, gene
transfection
human albumin
(Optison)
Ultrasound
one
bubble
contrast
agents
perfluorinated
microbubbles
H=human, R=rodent
Molecular imaging modalities
MR Spectroscopy
PET/CT
Optical
Imaging
SPECT/CT
Targeted
ultrasound
Positron emission tomography:
PET
18FDG
511 kev+
-o
180
511 kev
Radiotracer
PET-CT image
How is molecular imaging relevant to
cancer patient care?
metastasis
Imaging cellular
and molecular
phenomena
in vivo
malignant
M. Harisinghani
Patient selection
by genotype
D. Artemov
Diagnostic and
therapeutic agents
combine as
“theranostics”
S. Gambhir
Molecular imaging and cancer
Optical: Activatable
fluorescence
for intestinal adenoma
MR: Amide proton
transfer imaging to
assess brain tumor
characteristics
U. Mahmood
Nuclear:
PSMA imaging
for prostate
cancer
Nuclear:
[18F]FHBG for
tracking T cells
J. Babich
S. Gambhir
P. Van Zijl
What is the state of molecular
imaging now?

~90 % of clinical molecular imaging is PET and
SPECT

Optical, other modalities on the horizon

Nanoparticles, bacteria, new probes used to image
critical cancer processes (cell death, tumor
proliferation, angiogenesis, hypoxia) on the horizon

Reporter-probe pairs are being generated for
molecular-genetic imaging