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PET imaging targeting the prostate membrane-specific antigen (PSMA) has demonstrated high potential in localizing disease in prostate cancer. In addition to prostate cancer, both benign and malignant lesions have been reported to highly express PSMA (e.g. ganglia, parathyroid adenoma, lung, thyroid, and renal cancers [1,2,3]). Here, we describe the case of a 71-year-old male patient who was referred for imaging of biochemical recurrent prostate cancer (Gleason Score 7b, iPSA 116 ng/ml, s/p radical prostatectomy, PSA at imaging 0.32 ng/ml). [18F]rhPSMA-7-PET/CT showed high PSMA-ligand uptake in an expansile lytic bone lesion of the sternum, a small local recurrence and a bone lesion. The lesion of the sternum showed a lobular appearance, a shell-like periosteal reaction, and matrix calcifications (A PET MIP, B fused PET/CT, C PET only, D axial CT only, E sagittal CT only showing a sharply demarcated lesion, red arrows indicate the lesion, green arrow indicates a bone lesion, pink a local recurrence) and exhibited high T2-weighted signal intensity (F) and septonodular contrast enhancement (G) on magnetic resonance imaging. Given this morphological appearance, metastasis seemed unlikely and the subsequent biopsy and surgery confirmed the diagnosis of a grade 3 chondrosarcoma. Immunohistochemistry showed that PSMA was mainly expressed in small intralesional blood vessels/capillaries (histological slices H, yellow arrow: PSMA-staining; blue arrow: hyaline matrix). This is in line with previous reports demonstrating high PSMA-expression in vascular regions [2, 4, 5].
In summary, this case illustrates the potential pitfalls in PSMA-ligand PET-imaging given that PSMA-expression is also present in non-prostate cancer lesions and highlights the necessity of thorough analysis of the accompanying cross-sectional imaging modality.
References
Verburg FA, et al. First evidence of PSMA expression in differentiated thyroid cancer using [(6)(8)Ga]PSMA-HBED-CC PET/CT. Eur J Nucl Med Mol Imaging. 2015;42(10):1622–3.
Pfob CH, et al. Pitfalls in Ga-68-PSMA-PET/CT: incidental finding of parathyroid adenoma. Eur J Nucl Med Mol Imaging. 2019;46(4):1041.
Sheikhbahaei S, et al. Pearls and pitfalls in clinical interpretation of prostate-specific membrane antigen (PSMA)-targeted PET imaging. Eur J Nucl Med Mol Imaging. 2017;44(12):2117–36.
Silver DA, et al. Prostate-specific membrane antigen expression in normal and malignant human tissues. Clin Cancer Res. 1997;3(1):81–5.
Liu H, et al. Monoclonal antibodies to the extracellular domain of prostate-specific membrane antigen also react with tumor vascular endothelium. Cancer Res. 1997;57(17):3629–34.
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ME is a consultant for Blue Earth Diagnostics Ltd., Novartis and Janssen. Patent application for rhPSMA (ME). All other authors do not have conflicts of interest.
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Feuerecker, B., Mogler, C., Wörtler, K. et al. Pitfalls in PSMA imaging: [18F]rhPSMA-7-PET/CT reveals presence of chrondrosarcoma. Eur J Nucl Med Mol Imaging 48, 3007–3008 (2021). https://doi.org/10.1007/s00259-021-05254-x
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DOI: https://doi.org/10.1007/s00259-021-05254-x