Extending Amyloidosis Diagnosis: A Rare Case of Peritoneal AL Amyloidosis Revealed by 18F-FDG PET/CT and 99mTc-PYP SPECT/CT

Arslan D. F., Inal E., Isik E. G., Sanli Y.

Clinical Nuclear Medicine, vol.50, no.3, 2025 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 50 Issue: 3
  • Publication Date: 2025
  • Doi Number: 10.1097/rlu.0000000000005603
  • Journal Name: Clinical Nuclear Medicine
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, EMBASE
  • Keywords: 18F-FDG PET/CT, 99mTc-PYP scintigraphy, AL amyloidosis, peritoneal amyloidosis
  • Istanbul University Affiliated: Yes

Abstract

We present a case with systemic amyloidosis secondary to immunoglobulin light-chain amyloidosis (AL amyloidosis), which 18F-FDG PET/CT and 99mTc-PYP scintigraphy revealed amyloid deposition in the peritoneum, omentum, and mesentery. AL amyloidosis is characterized by the proliferation of clonal plasma cells and increased production and extracellular accumulation of immunoglobulin light chains, leading to organ malfunction. Even though AL amyloidosis can affect the gastrointestinal system, peritoneal involvement is rarely observed. PET/CT and SPECT/CT images showed moderate to slightly increased tracer uptake in affected organs.