Non-FDG PET/CT in Diagnostic Oncology: a pictorial review

Abstract

Positron emission tomography/computed tomography (PET/CT) is currently one of the main imaging modalities for cancer patients worldwide. Fluorodeoxyglucose (FDG) PET/CT has earned its global recognition in the modern management of cancer patients and is rapidly becoming an important imaging modality for patients with cardiac, neurological, and infectious/inflammatory conditions. Despite its proven benefits, FDG has limitations in the assessment of several relevant tumours such as prostate cancer. Therefore, there has been a pressing need for the development and clinical application of different PET radiopharmaceuticals that could image these tumours more precisely. Accordingly, several non-FDG PET radiopharmaceuticals have been introduced into the clinical arena for management of cancer. This trend will undoubtedly continue to spread internationally. The use of PET/CT with different PET radiopharmaceuticals specific to tumour type and biological process being assessed is part of the personalised precision medicine approach. The objective of this publication is to provide a case-based method of understanding normal biodistribution, variants, and pitfalls, including several examples of different imaging appearances for the main oncological indications for each of the new non-FDG PET radiopharmaceuticals. This should facilitate the interpretation and recognition of common variants and pitfalls to ensure that, in clinical practice, the official report is accurate and helpful. Some of these radiopharmaceuticals are already commercially available in many countries (e.g. 68 Ga-DOTATATE and DOTATOC), others are in the process of becoming available (e.g. 68 Ga-PSMA), and some are still being researched. However, this list is subject to change as some radiopharmaceuticals are increasingly utilised, while others gradually decrease in use.

Current State of Breast Cancer Diagnosis, Treatment, and Theranostics

“…The improved spatial resolution and sensitivity of PET scanners dedicated to breast (positron emission mammography) has allowed its clinical application in the study of primary tumors [ 79 , 80 ]. Numerous studies have shown that hybrid imaging with 18 F-FDG PET/CT provides information about the cellular glucose uptake, which is elevated in malignant lesions [ 81 , 82 , 83 , 84 ]. Jørgensen et al observed significantly reduced uptake of 18 F-FDG by tumor cells following nanoparticle-assisted photothermal therapy, indicating that it can be effectively used as a marker to assess treatment responses [ 85 ].…”

Clinical Results of Fibroblast Activation Protein (FAP) Specific PET and Implications for Radiotherapy Planning: Systematic Review

“…One modality which has provided continuous innovation and therefore seen increasing use has been the positron emission tomography-computed tomography (PET-CT), mainly due to the development of new tracers in addition to the most prevalent 18 F-fluorodeoxyglucose ( 18 F-FDG) [ 1 ]. PET-CTs are nowadays recommended for a variety of clinical indications and have been shown to alter the management of oncology patients in many cases [ 2 , 3 ].…”

Positron Emission Tomography in Merkel Cell Carcinoma

“…When injected intravenously, this molecule can cross the blood-brain barrier to reach the dopaminergic neurons where it is used as a precursor of the neurotransmitter dopamine. In the field of nuclear oncology, the main clinical application of imaging with 18 F-DOPA is for the management of NETs and brain tumors [81,82]. On the basis of the knowledge that the amino acid DOPA is a precursor of melanin, 18 F-FDOPA PET has also been experimentally applied in melanoma patients in combination with 18 F-FDG.…”