Senescence, immune microenvironment, and vascularization in cardiac myxomas

Contrast-enhanced echocardiographic diagnosis of benign and malignant cardiac tumors and its correlation with pathology

Background

This study aimed to explore the diagnostic value of contrast-enhanced echocardiography (CEE) in benign and malignant cardiac tumors and detect the correlation of CEE parameters and immunohistochemistry (IHC) markers.

Methods

The data of 44 patients with cardiac tumors confirmed by pathology were reviewed. Lesions were examined before surgery using transthoracic echocardiography (TTE) and CEE with time-intensity curve analysis. The expression of CD31, VEGF and Ki67 was measured by IHC staining. Microvessel density (MVD) was quantified via IHC for CD31. The clinical variables, TTE, CEE and IHC parameters were compared between benign and malignant cardiac tumors. Receiver operating characteristic curve were used to analyze the value of factors in predicting malignant cardiac tumors. The correlation between CEE and IHC parameters was analyzed.

Results

Among 44 cardiac tumors, 34 were benign and 10 were malignant. There were significant differences in the TTE parameters (pericardial effusion, tumor boundary, diameter, basal width), CEE parameters (tumor peak intensity (TPI), peak intensity ratio of tumor to myocardium (TPI/MPI), area under time-intensity curve (AUTIC)) and IHC parameters (Ki67, MVD, CD31, VEGF) between the benign and malignant tumor groups (all P < 0.05). Receiver operating characteristic curve analysis showed that the CEE and IHC parameters had diagnostic value in malignant cardiac tumors. There was a correlation between TPI/MPI and Ki67 (r = 0.62), AUTIC and Ki67 (r = 0.50), and AUTIC and CD31 (r = 0.56).

Conclusion

TTE and CEE parameters were different between benign and malignant cardiac tumors. CEE is helpful to differentiate the properties of cardiac tumors. There is a correlation between CEE parameters and IHC markers. AUTIC and TPI/MPI can reflect the proliferation and invasion of tumors.

Morphological characteristics of cardiac myxoma causing embolism: a series of 40 years of experience at a single institute

Systemic and cerebral embolisms are serious complications of associated with cardiac myxoma. Embolism risk reportedly depends on the gross and histological morphology. This study is aimed at analyzing the morphologic pattern of excised cardiac myxoma as a high-risk embolic cause. Between 1978 and April 2022, 116 surgical specimens of cardiac myxomas were recorded at the pathology department of our hospital. The tumors were classified into three types based on their macroscopic shapes and external morphology-round-smooth, irregular, and villous-to investigate the embolic complications. Of the 116 specimens, 106 macroscopic images of cardiac myxoma (89% were located in the left atrium) were prepared. Round-smooth types were found in 36 (34.0%) patients, irregular types in 32 (30.2%) patients, and the villous types in 38 (35.8%) patients. Multivariable analysis revealed that a villous external appearance was an independent predictor of embolic events (odds ratio: 8.7; 95% confidence interval: 2.4-42.1; p < 0.001). Villous external appearance of cardiac myxoma was associated with the highest risk of distal embolism.

Autophagy in cardiac myxoma: An important puzzle piece in understanding its inflammatory environment

BACKGROUND

Cardiac myxomas are rare, predominantly sporadic tumors that can cause heart failure and systematic inflammatory symptoms, and increase the risk of emboli. Their pathophysiology remains poorly understood, but intra-tumoral inflammation and senescence seem to be implicated in it. One of the principal cellular mechanisms implicated in tumor progression is autophagy, largely unknown in myxomas. Thus, our study aimed to investigate the presence of autophagic markers in myxomas and to correlate it with their immune microenvironment.

METHODS

Twenty-five cardiac myxomas were studied for the autophagic markers LC3B and p62/sequestosome 1 and were compared with markers of the immune microenvironment.

RESULTS

Most myxomas showed expression of both autophagic markers. We found a positive correlation between LC3B and PD-L1, as well as CD163, and a negative correlation between LC3B and CD8, CD20, CD138, and CD117 infiltration.

CONCLUSION

Our data not only confirm the presence of autophagic markers within cardiac myxomas but also suggest a possible association with their immune microenvironment.