68Ga-PSMA–Avid Liver Metastases From Colon Cancer, Not Visualized on FDG PET Scan

Abstract

Abstract 18F-FDG PET/CT scan is a well-known modality to assess distant metastases and treatment response in the patients with primary colon cancer. We are presenting an interesting case of 68Ga-PSMA–avid liver metastases in a 74-year-old man with colon cancer and recently diagnosed prostate cancer. The liver metastases were positive on initial FDG PET but lost FDG avidity on subsequent posttreatment FDG PET scans. Biopsy from the PSMA-avid liver lesions confirmed metastasis from colon origin. PSMA is expressed in various forms of tumor neovasculature other than prostate cancer with potential new applications as a theranostic agent in the future.