Foreign body granulomas masquerading as metastatic deposits

ABSTRACT

A 30-year-old male with a known case of rectal adenocarcinoma, post-low anterior resection (LAR) and oxaliplatin with capecitabine chemotherapy, presented with fluorodeoxyglucose (FDG)-avid extensive multiple peritoneal and hepatic deposits on Positron Emission Tomography-Computed Tomography (PET-CT), suggestive of metastatic disease. After histological examination, these lesions were pulse granulomas with vegetable matter deposits, causing a florid foreign body-type giant cell reaction. This case represents a rare presentation of foreign body granuloma masquerading as a metastatic deposit. It is an important diagnostic pitfall where benign foreign body granulomas can mimic metastatic disease both radiologically and clinically, emphasizing the role of histopathology in definitive diagnosis and guiding appropriate patient management.