The Long Journey of Cardiac Lymphoma Follow-up.

We are very thankful to Kim et al for their work.1) For the patient, the journey to survival was a long one. As the authors say—and is also our experience—it is a rare condition. It can certainly have a wide variety of confounding presentations such as chest pain2) and atrioventricular block.3) We have invariably found it devastating for the patients and a huge challenge for, firstly, establishing the diagnosis and, secondly, ensuring appropriate follow-up. For establishing diagnosis, a multimodality approach—as undertaken in this case—is invariably helpful.4)

For follow-up purposes, we have previously found fluorodeoxyglucose (FDG)-positron emission tomography (PET) more consistently helpful to differentiate functioning and viable tumour, especially when anatomical imaging modalities such as magnetic resonance imaging and transthoracic echocardiogram show residual tissue abnormality but it is unclear if that tumour is active.5) In this regard, we were surprised that the follow-up imaging showed near-normalisation on transthoracic echocardiography but not on FDG-PET. What do the authors postulate to explain this outcome, which we—and other readers, we are sure—would find surprising?