Calcified amorphous tumor presenting with rapid growth in the ascending aorta

A calcified amorphous tumor (CAT) is a rare, non-neoplastic cardiac mass frequently located in cardiac chambers, especially the mitral valve or annulus. Here, we report an exceedingly rare case of CAT as an atypical mobile mass in the ascending aorta in a 62-year-old man who was on hemodialysis for 11 years. The CAT grew rapidly within 3 months. We resected the mass, and he was discharged with no complications. This report shows that the CAT can grow rapidly, even in the aorta, and provides important information on the progression of this rare disease and its clinical features.