Differentiation of Discordant Lesions on Dual-Tracer PET/CT (68Ga-PSMA-11 and 18F-FDG) in Prostate Carcinoma: Diagnosis of Second Primary Malignancies

J Nucl Med Technol. 2023 Dec 5;51(4):339-342. doi: 10.2967/jnmt.123.265779.

Abstract

We present 2 cases of metastatic castration-resistant prostate carcinoma with discordant lesions on dual-tracer PET/CT (68Ga-PSMA-11 and 18F-FDG PET/CT), which on subsequent histopathologic evaluation revealed second primary malignancies of combined hepatocellular carcinoma and cholangiocarcinoma and poorly differentiated squamous cell carcinoma. These case illustrations emphasize the need to evaluate discordant lesions on dual-tracer PET/CT, which can lead to early diagnosis of second primary malignancies and thereby can provide better management in these patients.

Keywords: 68Ga-PSMA-11;18F-FDG; dual-tracer PET/CT; prostate carcinoma; second primary malignancy.

MeSH terms

  • Carcinoma, Hepatocellular*
  • Cell Differentiation
  • Fluorodeoxyglucose F18
  • Gallium Radioisotopes
  • Humans
  • Liver Neoplasms*
  • Male
  • Neoplasms, Second Primary*
  • Oligopeptides
  • Positron Emission Tomography Computed Tomography
  • Prostate
  • Prostatic Neoplasms* / diagnostic imaging
  • Prostatic Neoplasms* / pathology

Substances

  • gallium 68 PSMA-11
  • Fluorodeoxyglucose F18
  • Oligopeptides
  • Gallium Radioisotopes