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

Area of Science:

• Oncology
• Radiology
• Gynecology

Background:

• Endometriosis is a benign condition involving chronic inflammation and fibrosis.
• Accurate diagnosis of endometriosis can be challenging, sometimes mimicking other pathologies.

Purpose of the Study:

• To report the utility of 68Ga-FAPI-04 PET/CT in identifying endometriosis.
• To highlight a case where endometriosis findings were initially misdiagnosed as malignancy.

Main Methods:

• A 25-year-old woman with newly diagnosed gastric cancer underwent a 68Ga-FAPI-04 PET/CT scan.
• The scan revealed findings at the rectouterine pouch.

Main Results:

• The 68Ga-FAPI-04 PET/CT scan showed abnormal uptake in the rectouterine pouch.
• These findings were initially interpreted as peritoneal metastasis from gastric cancer.
• Pathologic examination confirmed the lesions to be endometriosis.

Conclusions:

• 68Ga-FAPI-04 PET/CT can visualize endometriosis, particularly in the rectouterine pouch.
• This imaging modality may lead to misdiagnosis if endometriosis is not considered, especially in patients with concurrent malignancies.