Incidental Detection of Radiotracer Uptake in Intracranial Dermoid Cyst on 18F-Prostate-Specific Membrane Antigen PET/CT During Staging for Prostate Carcinoma

Clin Nucl Med. 2021 May 1;46(5):e273-e275. doi: 10.1097/RLU.0000000000003465.

Abstract

A 68-year-old man underwent 18F-prostate-specific membrane antigen (PSMA) PET/CT for staging of a newly diagnosed prostate adenocarcinoma. Unexpectedly, PET/CT revealed high focal 18F-PSMA brain uptake, which initially was suspected for a brain metastasis. Corresponding CT and MRI scans revealed characteristic imaging features of an intracranial dermoid cyst at this site. This is an exceptional location for a dermoid cyst, which had been followed up conservatively with no substantial changes. This case shows that dermoid cyst should be added to the reported list of benign neoplasms that shows "false-positive" PSMA uptake during evaluation of patients with prostate carcinoma, representing a potential interpretative pitfall.

Publication types

  • Case Reports

MeSH terms

  • Aged
  • Antigens, Surface / metabolism*
  • Biological Transport
  • Dermoid Cyst / complications
  • Dermoid Cyst / diagnostic imaging*
  • Dermoid Cyst / metabolism
  • Fluorine Radioisotopes*
  • Glutamate Carboxypeptidase II / metabolism*
  • Humans
  • Incidental Findings*
  • Male
  • Neoplasm Staging
  • Positron Emission Tomography Computed Tomography*
  • Prostatic Neoplasms / complications*
  • Prostatic Neoplasms / pathology

Substances

  • Antigens, Surface
  • Fluorine Radioisotopes
  • FOLH1 protein, human
  • Glutamate Carboxypeptidase II
  • Fluorine-18