FDG PET/CT can assist lymphoma chemotherapy cardiotoxicity evaluation
Anthracycline chemotherapeutic agents are commonly employed in the treatment of lymphoma; however, their efficacy in combating the malignancy comes at a cost—they are cardiotoxic and are known to cause cardioditis and cardiomyopathy. A study presented at the recent Radiological Society of North America annual scientific conference sought to determine a relation between myocardial FDG metabolism with FDG PET/CT scanning and the use of anthracycline chemotherapeutic agents.

“Increased FDG metabolism by the myocardium has been shown to be a response to myocardial insult such as ischemia and inflammation,” said Srinesh Alle, MD, who presented the results of his team’s retrospective study, which was conducted at the Oschner Health System in New Orleans.

The scientists reviewed 24 consecutive patients who were newly diagnosed with lymphoma and underwent FDG-PET scanning before and after receiving cardiotoxic chemotherapy. All patients were newly diagnosed and the scans were performed on a GE Healthcare Discovery PET/CT system.

“No one knows what the exact mechanism of injury is with these anthracyclines, it is thought to be multi-factorial,” he said.

Myocardial FDG metabolism was measured in the initial PET scan (baseline, pre-chemotherapy) and after chemotherapy treatment. The difference in myocardial FDG metabolism was calculated in each patient and was correlated with cardiac function tests, when available, Alle said.

The group found that 21 (88 percent) of the 24 patients demonstrated a significant increase of myocardial FDG metabolism in the post-chemotherapy scans compared to their pre-chemotherapy scans.

According to Alle, the vast majority of the patients (86 percent) had greater than a 100 percent increase in FDG metabolism in the myocardium. He reported that three (12 percent) of the 24 patients demonstrated no significant change in myocardial FDG metabolism in their post-chemotherapy scans.

“Unfortunately, not enough cardiac function tests were available in these patients to determine whether increased uptake of FDG corresponded to a decline in cardiac function,” Alle noted.

Alle said that further research is needed to determine if this altered metabolism leads to a decline in cardiac function.

“The earliest manifestation of anthracycline cardiotoxicity may be at the molecular level, as evidenced by the altered myocardial metabolism of FDG before and after chemotherapy,” he observed.