Focal 68Ga-FAPI-04 Uptake in Endometriosis at the Rectouterine Pouch

Endometriosis is a benign condition characterized by chronic inflammation and fibrosis. We report the findings of endometriosis at the rectouterine pouch on 68 Ga-FAPI-04 PET/CT scan in a 25-year-old woman. The finding was initially thought as peritoneal metastasis from her newly diagnosed gastric cancer. However, subsequent pathologic examination confirmed that it was endometriosis.