Vol. 5, Issue 1, Part A (2023)

In the last century, there have been significant advancements in the treatment of cancer through the use of ionizing radiation therapy. These advancements are mainly due to the progress made in medical imaging. The introduction of computed tomography (CT) has greatly improved the planning of treatment. However, CT remains the only imaging modality used for dose calculation in three dimensions, despite its limitations. More modern imaging techniques such as magnetic resonance imaging (MRI) and positron emission tomography are primarily used in the treatment-planning process. MRI, with its superior tissue contrast and resolution compared to CT, aids in tumor delineation. PET provides metabolic data along with anatomical information from CT and MRI. Clinicians can make more informed decisions about the most effective treatment options for cancer patients by analyzing and visualizing the metabolic profile, active pathways, and genetic markers of tumors. This knowledge can be used to compare different tumors and assess the heterogeneity of a specific tumor. The aim is to quickly determine the effectiveness and location of a chosen therapy. In the future, multimodality scanners such as PET/CT and PET/MR will provide the most precise information for targeting tumors in the era of the human genome.