Hot-clot artifact in lung parenchyma on [68Ga]Ga-PSMA-11 PET/CT can mimic prostate cancer metastasis

Document Type : Case Report

Authors

1 Razavi Cancer Research Center, Razavi Hospital, Imam Reza International University, Mashhad, Iran

2 Nuclear Medicine Research Center, Mashhad University of Medical Sciences, Mashhad, Iran

Abstract

[68Ga]Ga-PSMA-11 PET/CT scan is an important whole-body imaging tool in oncology and is specifically used for staging and re-staging of prostate cancer, in recent years. Findings of significant focal accumulation of PSMA in the lung parenchyma without corresponding CT abnormalities are challenging and may be a cause for false positive interpretation of metastasis, caused by pulmonary microembolism due to hot-clot artifacts, as previously described in 2-[18F]FDG PET/CT studies. Here we present an unusual case of focal PSMA uptake in lung parenchyma without structural lesions on CT scan, which we believe is due to hot clot because of faulty injection techniques.

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