Incidental Finding of a Pancreatic Adenocarcinoma on [68Ga]Ga-PSMA-11 PET/CT in a mCRPC patient under [177Lu]Lu-PSMA-617 Radioligand Therapy

Introduction

Prostate-specific membrane antigen (PSMA) is a transmembrane type II glycoprotein with folate hydrolase and neurocarboxypeptidase activity generally expressed by prostate epithelium and upregulated on the surface of prostatic adenocarcinoma (PCa) cells. Based on its exceptionally high level of PSMA expression by tumor cells, PSMA-based imaging as well as PSMA-based radioligand therapy (RLT) regimens have been introduced in the management of PCa patients. However, PSMA expression has also been demonstrated in the neovasculature of different solid tumor tissues. Even if the underlined mechanism is not completely understood, some preclinical data suggested that PSMA might be involved in cancer-related angiogenesis by degrading the extracellular matrix and participating in integrin signal transduction [1]. In this scenario, positron emission tomography/computed tomography (PET/CT) imaging by using Gallium-68 (⁶⁸Ga) or Fluoro-18 (¹⁸F)-labeled PSMA ligands can play a role also in tumors beyond PCa. Although the growing interest in the diagnostic performance of PSMA ligands in different solid tumors, data remain limited for some subtypes [2].

Here we report the clinical case of a 68-year-old man under [¹⁷⁷Lu]Lu-PSMA-617 therapy for metastatic castration-resistant prostate cancer (mCRPC) with the incidental detection of a pancreatic adenocarcinoma on the restaging [⁶⁸Ga]Ga-PSMA-11 PET/CT.

Publication History

Received: 02 November 2023

Accepted: 27 November 2023

Article published online:
08 January 2024

• References

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