Imaging Features Differentiating Between Cardiac Sarcomas and Hematologic Neoplasms

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.

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.

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.

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.