Changes in 18F-FDG PET-CT Appearances of Treated Malignant Melanoma Metastases within the Right Atrium

Abstract

18 F-FDG PET-CT plays an important role in the management of malignant melanoma. Cardiac metastases of melanoma are relatively uncommon, but when present they often manifest with cardiac arrhythmia and cardiac failure. Once treated successfully, lesions in the heart reduce in size and FDG-uptake, while signs of cardiac arrhythmia and cardiac failure may resolve. With a background of normal physiological FDG-uptake in cardiac muscle, a careful observation is required when cardiac metastases are clinically suspected. We report a patient with right atrial metastases of melanoma who presented with new onset atrial fibrillation, and in whom the cardiac lesion reduced in size and FDG-uptake following appropriate treatment, and signs of cardiac arrhythmia spontaneously resolved. The authors believe this is the first set of PET-CT appearances of pretreatment and treated cardiac metastases of melanoma in the literature.