A 68Ga-FAPI-46 PET/CT Imaging Pitfall in Assessing Residual Gastric Cancer Early After Chemotherapy

Clin Nucl Med. 2022 Jul 1;47(7):644-645. doi: 10.1097/RLU.0000000000004143. Epub 2022 Mar 31.

Abstract

After neoadjuvant chemotherapy, preoperative imaging with 68Ga-FAPI-46 PET/CT showed a similar level of tracer uptake at the location of the primary tumors in 2 patients with gastric cancer. Postoperative histopathology revealed residual malignant cells only in one of the patients, whereas the elevated FAPI uptake in the other patient correlated to an inflammatory reaction and fibrosis. With this case, we would like to highlight that an increased FAPI uptake in inflammatory and fibrotic tissue early after chemotherapy may represent a potential interpretation pitfall. Further studies evaluating the clinical application of FAPI-PET in assessing residual cancer tissue are warranted.

MeSH terms

  • Gelatinases
  • Humans
  • Membrane Proteins
  • Neoplasm, Residual / diagnostic imaging
  • Positron Emission Tomography Computed Tomography* / methods
  • Quinolines
  • Serine Endopeptidases
  • Stomach Neoplasms* / diagnostic imaging
  • Stomach Neoplasms* / drug therapy

Substances

  • FAPI-46
  • Membrane Proteins
  • Quinolines
  • Serine Endopeptidases
  • Gelatinases