Diagnostic challenges in primary cardiac lymphoma, the opportunity of 18F-FDG PET/CT integrated with contrast-enhanced CT

Imaging Features Differentiating Between Cardiac Sarcomas and Hematologic Neoplasms

PURPOSE

The aim of the study is to assess the efficacy of computed tomography (CT) and positron emission tomography (PET)/CT findings in differentiating between cardiac sarcoma and cardiac hematologic neoplasms, which are rare but potentially lethal primary cardiac malignancies.

MATERIALS AND METHODS

We searched the electronic medical record for pathology-proven cases from 2012 to 2023, finding 69 patients (46 sarcomas, 23 cardiac hematologic neoplasms). Imaging features including tumor size, atrioventricular (AV) groove involvement, right coronary artery (RCA) encasement by 180°, pericardial effusion, lymphadenopathy, and metabolic activity on fluorodeoxyglucose PET were reviewed by a radiology fellow. Statistical analysis was performed using Fisher exact test and Wilcoxon test.

RESULTS

Cardiac sarcoma patients were younger (median age 49 years) compared to patients with cardiac hematologic malignancies (66 years, P = 0.006). While tumor size and chamber involvement were similar between the 2 categories, hematologic malignancies exhibited a notable predilection for AV groove involvement (70% vs 43%, P = 0.04) and RCA encasement (52% vs 26%, P = 0.02). Pulmonary metastases were more frequent in sarcoma cases (33% vs 4%, P = 0.006). There was no significant difference in fluorodeoxyglucose uptake. Lymphadenopathy was similar between the 2 disease groups. A decision tree constructed using AV groove involvement and patient age achieved 75% accuracy in predicting the diagnosis of the mass.

CONCLUSIONS

Overall, there is a substantial overlap in imaging features of cardiac sarcomas and hematologic malignancies involving the heart. Involvement of the AV groove and RCA encasement can allow a radiologist to favor hematologic malignancy. Ultimately, biopsy is required to establish a diagnosis.

Review of cardiovascular imaging in the Journal of Nuclear Cardiology 2022: positron emission tomography, computed tomography, and magnetic resonance

In 2022, the Journal of Nuclear Cardiology® published many excellent original research articles and editorials focusing on imaging in patients with cardiovascular disease. In this review of 2022, we summarize a selection of articles to provide a concise recap of major advancements in the field. In the first part of this 2-part series, we addressed publications pertaining to single-photon emission computed tomography. In this second part, we focus on positron emission tomography, cardiac computed tomography, and cardiac magnetic resonance. We specifically review advances in imaging of non-ischemic cardiomyopathy, cardio-oncology, infectious disease cardiac manifestations, atrial fibrillation, detection and prognostication of atherosclerosis, and technical improvements in the field. We hope that this review will be useful to readers as a reminder to articles they have seen during the year as well as ones they have missed.

PET/CT morphology and cardiac conduction disorders help discriminate primary cardiac lymphoma from primary cardiac sarcoma

BACKGROUND

Primary cardiac lymphoma (PCL) and primary cardiac sarcoma (PCS) are similar in clinical presentation but differ in management and outcomes. We aim to explore the role of PET morphology and clinical characteristics in distinguishing PCL from PCS.

METHODS

Pretreatment 18F-FDG PET/CT and contrast-enhanced CT were performed in PCL (n = 14) and PCS (n = 15) patients. Patient demographics, overall survival, and progression-free survival were reviewed. PET/CT morphological and metabolic features were extracted. Specifically, R_Kurtosis, a PET-morphology parameter reflecting the tumor expansion within the heart, was calculated.

RESULTS

Compared with PCS, PCL occurred at an older age, resulted in more cardiac dysfunctions and arrhythmias, and showed higher glucometabolism (SUVmax, SUVpeak, SUVmean, MTV, and TLG). Curative treatments improved survival for PCL but not for PCS. Multivariable logistic regression identified R_Kurtosis (OR = 27.025, P = .007) and cardiac conduction disorders (OR = 37.732, P = .016) independently predictive of PCL, and classification and regression tree analysis stratified patients into three subgroups: R_Kurtosis ≥ 0.044 (probability of PCL 88.9%), R_Kurtosis < 0.044 with conduction disorders (80.0%), and R_Kurtosis < 0.044 without conduction disorders (13.3%).

CONCLUSION

PET-derived tumor expansion pattern (R_Kurtosis) and cardiac conduction disorders were helpful in distinguishing PCL from PCS, which might assist the clinical management.