Unsuspected Uterine Metastasis of Breast Carcinoma Diagnosed by 18F-FDG PET/CT

A 50-year-old woman with a history of bilateral lobular carcinoma of the breast in 1995 and 2001 was treated with mastectomy, axillary lymphadenectomy, chemotherapy, and hormone therapy which achieved a complete response. In 2009, the patient developed a progressive elevation of tumor markers. A CT scan was performed showing no suspicious malignant lesions. She was referred for F-18-FDG PET/CT and the images revealed highly increased tracer uptake in the uterus suggestive of malignancy. The patient underwent hysterectomy with bilateral double adnexectomy and a histopathological diagnosis of massive carcinomatous infiltration of breast lobular carcinoma was done.