Uterine Intravenous Leiomyomatosis with Intracardiac Extension and Pulmonary Benign Metastases on FDG PET/CT: A Case Report.

A 48-year-old woman presented with a 50-day history of irregular vaginal bleeding and lower abdominal pain. Ultrasound indicated an extremely large occupying lesion in the pelvic cavity that was highly suggestive of malignancy. Fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) was performed to further assess the nature of pelvic abnormality. PET/CT images demonstrated a diffusely lobulated mass ranging from cervix up to the inferior pole of kidneys with mild FDG uptake. Simultaneously, multiple nodules in bilateral lungs and a hypodense lesion in the right ventricle were shown without FDG-avidity. Based on the imaging results, the presumptive diagnosis was uterine intravenous leiomyomatosis with intracardiac extension and pulmonary benign metastases, which was subsequently confirmed by MRI and the lesion biopsy.