TOTEM has been more successful than we had imagined. It is enabling us to accelerate research on the new scanners while taking advantage of the new technology to develop and optimise scanning protocols to further enhance clinical diagnosis and research data acquisition.
Gary Cook, Professor of Molecular Imaging and Lead Investigator on TOTEM study
16 June 2026
TOTEM study reaches milestone with 1,000th participant scanned
1,000 participants have been recruited to the TOTEM study, which aims to establish evidence-based protocols for total-body PET scanning.
The TOTEM study launched in March 2025 when two next-generation Siemens Healthineers Biograph Vision Quadra Total-Body PET scanners were installed at the King's College London and Guy’s and St Thomas’ PET Centre. The scanners are two of only four systems in the UK.
Total-body PET (TBP) scanners are 10 to 40 times more sensitive than conventional PET/CT scanners and can capture the whole body simultaneously rather than in sections, resulting in better image quality, lower radiation doses and faster scan times.
However, as the technology is still new, no standardised, evidence-based protocols have been established.
TOTEM aims to address this by collecting additional scan data from patients already undergoing clinically indicated PET/CT scans, to develop and optimise protocols for the acquisition and analysis of TBP scans for use in research and clinical practice. The study will also explore how to harness machine learning and AI to improve image analysis.
For patients, this could mean earlier and more accurate detection of cancers such as lung cancer, lymphoma, melanoma and prostate cancer, better monitoring of treatment response and lower radiation exposure.
Reaching 1,000 participants reflects the strength of the multidisciplinary team behind the study, which brings together administrative, research delivery, nursing, physics, technologist and clinical academic expertise from across the PET Centre, King's and GSTT.
The study has also opened five sub-studies inviting participants to undergo additional research scans, with four more in final preparation, and nearly 100 additional research scans have already been completed. Over 1,000 standard-of-care scans and 140 anonymised datasets have been shared with King's academics for research purposes, including those working on advanced AI methods.
TOTEM's protocols have been shared across all other UK TBP sites through the National PET Imaging Platform, and internationally with the Peter MacCallum Cancer Centre in Australia.
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Professor of Molecular Imaging