Continuous, Preclinical Activity Reconstruction in Lu-based Radiopharmaceutical Therapy Using a Sparse Uncollimated γ-Sensor Network.
[PURPOSE] Lu-based radiopharmaceutical therapy (RPT) has shown increasing promise in the treatment of neuroendocrine and metastatic prostate cancer.
APA
Lall R, Evans M, et al. (2026). Continuous, Preclinical Activity Reconstruction in Lu-based Radiopharmaceutical Therapy Using a Sparse Uncollimated γ-Sensor Network.. International journal of radiation oncology, biology, physics. https://doi.org/10.1016/j.ijrobp.2026.02.224
MLA
Lall R, et al.. "Continuous, Preclinical Activity Reconstruction in Lu-based Radiopharmaceutical Therapy Using a Sparse Uncollimated γ-Sensor Network.." International journal of radiation oncology, biology, physics, 2026.
PMID
41713513
Abstract
[PURPOSE] Lu-based radiopharmaceutical therapy (RPT) has shown increasing promise in the treatment of neuroendocrine and metastatic prostate cancer. Delivering optimal radiation dose to tumors while minimizing dose to organs-at-risk (OAR) remains an unmet need because of significant patient-to-patient heterogeneity in treatment response, necessitating multiple snapshots of the in vivo activity distribution. Toward this goal, here we present a high temporal resolution activity reconstruction method demonstrated on preclinical prostate cancer models.
[METHODS AND MATERIALS] Using a priori knowledge of tumor locations from a pretherapy scan (eg, positron emission tomography/computed tomography), we have developed a low-cost, sparse sensor network to reconstruct the real-time tumor and OAR activity in preclinical cancer models. The proposed system was successfully validated with: (1) a small custom phantom filled with [Lu]Lu-prostate-specific membrane antigen (PSMA)-617; and (2) 4 mice models, bearing varying numbers of tumors from 2 human prostate cancer cell lines (PC3-PIP, PC3-flu), to which [Lu]Lu-PSMA-617 RPT was administered. Uncollimated γ counts using the developed network were acquired outside of the mouse at 10 minutes post-injection, 6 hours, 12 hours, 24 hours, and 48 hours post-injection.
[RESULTS] The developed system's total tumor activity and percent injected activity per milliliter of tissue (%IA/mL) reconstruction in tumors, kidneys, and bladders is highly linear with the total tumor activity (R = 0.991) and %IA/mL (R = 0.994) from state-of-art small-animal single photon emission computed tomography (SPECT). Acquisition and reconstruction were performed at a 1-minute temporal resolution, >30 times faster than conventional small-animal SPECT imaging, allowing for the ability to capture fast kinetics at early time points and create close-to continuous time-activity curves at a fraction of the cost of small-animal SPECT systems.
[CONCLUSIONS] The system can be used for high temporal resolution preclinical activity reconstruction, and motivates clinical adaptation in order to improve Lu-based RPT quality and safety through frequent activity distribution measurements of multiple tumors and OAR.
[METHODS AND MATERIALS] Using a priori knowledge of tumor locations from a pretherapy scan (eg, positron emission tomography/computed tomography), we have developed a low-cost, sparse sensor network to reconstruct the real-time tumor and OAR activity in preclinical cancer models. The proposed system was successfully validated with: (1) a small custom phantom filled with [Lu]Lu-prostate-specific membrane antigen (PSMA)-617; and (2) 4 mice models, bearing varying numbers of tumors from 2 human prostate cancer cell lines (PC3-PIP, PC3-flu), to which [Lu]Lu-PSMA-617 RPT was administered. Uncollimated γ counts using the developed network were acquired outside of the mouse at 10 minutes post-injection, 6 hours, 12 hours, 24 hours, and 48 hours post-injection.
[RESULTS] The developed system's total tumor activity and percent injected activity per milliliter of tissue (%IA/mL) reconstruction in tumors, kidneys, and bladders is highly linear with the total tumor activity (R = 0.991) and %IA/mL (R = 0.994) from state-of-art small-animal single photon emission computed tomography (SPECT). Acquisition and reconstruction were performed at a 1-minute temporal resolution, >30 times faster than conventional small-animal SPECT imaging, allowing for the ability to capture fast kinetics at early time points and create close-to continuous time-activity curves at a fraction of the cost of small-animal SPECT systems.
[CONCLUSIONS] The system can be used for high temporal resolution preclinical activity reconstruction, and motivates clinical adaptation in order to improve Lu-based RPT quality and safety through frequent activity distribution measurements of multiple tumors and OAR.