A comprehensive systematic literature review on the use of the Standardised Uptake Value (SUV) for the PET imaging of obese patients

Abstract

Background: Positron Emission Tomography (PET) imaging makes use of the Standardised Uptake Value (SUV) for quantitative analysis, to stage tumours and to assess tumour response to therapy in cancer patients. However, the accuracy and reliability of SUV measurements in obese patients have been questioned due to variations in body composition, potentially leading to misdiagnosis and ineffective treatment planning. Objectives: This study reviewed the available literature to assess if the SUV measurement is suitable for obese patients and to highlight potential superior methods. Research Methodology: Literature was reviewed systematically, focusing on publications from 2014 to 2024, to gather updated data. The literature was searched in the following databases: Hy-Di, Pub-Med and ScienceDirect, using the controlled keywords: ‘obese’, ‘PET’ and ’Standardised Uptake Value’. Relevant articles were selected using the PICO method to ensure the inclusion of high-quality and appropriate studies. 124 articles were found in total. 20 articles were chosen after reading their title and abstract, and 13 articles remained after reading their full text. Thereafter, data was extracted for qualitative meta-analysis. Results: The data extracted showed a significant overestimation of SUV values in obese patients, which can lead to erroneous diagnoses and suboptimal treatment planning. Analysis indicated that SUVs normalized by lean body mass (SUL) and body surface area (SUA) provided more accurate measurements compared to traditional SUV calculations. Metrics normalised by body mass index (BMI) and Fluorodeoxyglucose (FDG) were also proposed. These metrics demonstrated improved reliability, suggesting their viability for better clinical outcomes in obese patients. Conclusions and Recommendations: Results showed that the SUV measurement is not suitable for obese patients and may affect their diagnosis and treatment outcome. Metrics such as SUL and SUA offer more accurate and reliable alternatives, however, further research is required.