Abstract

Molecular imaging is rapidly gaining recognition as a tool with the capacity to improve every aspect of cancer care. Anatomic imaging will continue to play a role in cancer management, but, it is still limited in its ability to deliver metabolic and biological information. A modern personalized oncologic approach requires an understanding of cancer traits as tumors usually display several structural, physiologic, and molecular changes that can be assessed using molecular imaging. Different imaging techniques are useful for this role, including positron emission tomography (PET)¹, single-photon emission computed tomography (SPECT)², ultrasound (US)³, optical imaging⁴, magnetic resonance imaging (MRI), and magnetic resonance spectroscopy (MRS)⁵. These imaging techniques enable the evaluation of unseen tumor characteristics by conventional techniques improving tumor diagnosis and management. Recent advances in molecular MR imaging techniques have opened up new perspectives in imaging biological molecules within the tumor microenvironment, by using applications such as hyperpolarized tracers^6,7, the use of nanoparticles⁸, CEST agents⁹, etc. The last has emerged as a promising approach that can evaluate molecules other than water, thus providing increased sensitivity for in vivo imaging of tumor metabolism. CEST-based applications for the investigation of the tumor microenvironment, such as APT¹⁰, glucose and its analogs^11-13, tumor acidosis¹⁴, GAGs^15,16, and reporter genes¹⁷ imaging will be presented. Using these modalities may change the current primarily technology-driven approach of diagnostic imaging into a more disease-oriented approach for both basic research and clinical application. Eventually, biomedical imaging will become more and more multimodal in nature, as different anatomic and molecular imaging techniques can complement each other. Molecular imaging may serve in every aspect of oncology practice, thus, it is expected to have a major impact on our understanding of how cancer arises.

Acknowledgements

No acknowledgement found.

References

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