Table 1.

Molecular imaging for breast cancer

Modality	Indication	Advantages	Disadvantages
Radionuclide imaging
Positron emission tomography	Detection	Wide range of molecular imaging probes	Limited spatial resolution (improved with use of non-contrast computed tomography)
	Response evaluation Tumor characterization	Tracer imaging without perturbing biologic system
			Some radiation exposure
Positron emission mammography	Detection Tumor characterization	More sensitive for smaller tumors Higher spatial resolution	Increased radiation dose Visualization of posterior lesions Variable uptake of 18F-fluorodeoxyglucose (FDG) in small and less metabolically active tumors
Breast-specific gamma imaging	Detection	More sensitive for smaller tumors Heavy compression of breast tissue not required	Associated with radiation exposure Best combined with anatomic imaging (mammography) for optimal screening Longer imaging time
			Some radiation exposure
Magnetic resonance
Magnetic resonance imaging (MRI), especially dynamic contrast-enhanced MRI and targeted contrast agents	Tumor characterization	Quantification of tumor perfusion and tumor capillary permeability	Confined space Contrast design limited by need for magnetic atom
Magnetic resonance spectroscopy	Tumor characterization	Can measure wide range of molecules No contrast necessary	Limited spatial resolution Challenging to obtain high-quality spectra in routine imaging
Ultrasound, especially with contrast enhancement	Detection Tumor characterization	Highly portable, inexpensive Molecular microbubble agents possible	Operator dependence Contrast agents confined to vascular space thus far
Optical imaging	Tumor characterization	Inexpensive, highly portable, and does not necessarily require a contrast agent	Limited depth penetration, challenging spatial localization, and operator dependence