Molecular and structural imaging in oncology, improvements and perfection “…the most effective multimodality approach and a significant advance for examining patients with cancer” *Houseni, M. & **Alavi, A. *MD, Department of Radiology, National Liver Institute, Menoufya University and Alfa scan, Egypt,**MD, MD (Hon), PhD (Hon), DSc (Hon), Department of Radiology, Hospital of the University of Pennsylvania, Philadelphia, PA. USA

Cancer is a major health problem and a
leading cause of death in the world even if
adequately treated. It will continue to be a
chronic and debilitating disease. The key to
improving the overall quality of life and to
decrease lingering morbidity in cancer
depends on continuous monitoring of
disease activity, accurate staging, early
detection of recurrence and initiation of
appropriate and effective treatment.
Obviously, there are very complex
undertakings in spite of major advances in
recent years in medical imaging and other
diagnostic initiatives. By now it has become
clear that structural imaging with CT and
MRI suffers from many shortcomings and
cannot be relied upon solely for optimal
management of these patients.
Positron emission tomography (PET) is a
molecular imaging technology which
utilizes tracers for assessing metabolic and
biochemical pathways in a non-invasive and
quantitative manner. By now, its role in
oncology is well established by its ability to
assess and characterize the metabolic and
functional parameters of malignant tissues
[1, 2]. PET/CT and PET-MR fusion imaging
is emerging as the most effective
multimodality approach and a significant
advance for examining patients with cancer.
The unique advantage of combined
molecular and structural information
provided by these multimodalities is to
exploit the advantages of both and evaluate
their role in many complex settings [3].
A large number of radiolabeled compounds
targeting specific molecules or biochemical
pathways have been and continue to be
synthesized and validated as PET tracers.
The leading tracer that is being widely used
is 18F-fluorodeoxyglucose (FDG). The
concept of the FDG technique was born in
1973 and was tested in 1976 at the
University of Pennsylvania and ever since
the critical role of molecular imaging in
medicine emerged around the globe. This
glucose analogue imitate glucose
metabolism in the healthy and diseased
tissue [4]. The idea behind using FDG in
cancer is that the malignant cells are
characterized by enhanced glucose
consumption [5]; hence FDG-PET imaging
allows detection and characterization of
cancer based on the presence and the degree
of 18F-FDG uptake. The evolution of FDGPET
from a basic science and experimental
undertaking to a powerful clinical modality
has lead down a strong foundation for
molecular imaging as a new specialty in
medicine.