Epicardial Amyloidoma Mimicking Secondary Cardiac Lymphoma

Figures

• 

  Visual Summary. Epicardial Mass in a Patient With Indolent CD5-Positive B-Cell Lymphoma, IgG Lambda Monoclonal Gammopathy, and Echocardiographic Findings Suggestive of Amyloidosis Differential diagnosis included cardiac amyloidosis, Erdheim-Chester disease, and secondary cardiac lymphoma. Following no significant change after rituximab therapy, surgical biopsy demonstrated extensive Congo red–positive amyloid deposition associated with a lambda-restricted plasma cell infiltrate and a small CD5-positive B-cell population, establishing the diagnosis of epicardial amyloidoma. The patient ultimately died from noncardiac causes. AL = amyloid light chain amyloidosis; ATTR = transthyretin amyloidosis; ECV = extracellular volume; LGE = late gadolinium enhancement; MRI = magnetic resonance imaging.

• 

  Figure 1. Bull's-Eye Plot of Longitudinal Strain Demonstrating the Characteristic Apical Sparing Pattern (“Cherry-on-Top”) The global longitudinal strain is reduced (−11.3%).

• 

  Figure 2. Diastolic Evaluation Showing Restrictive Mitral Inflow Pattern Evaluation showed an E/A ratio of 2.36 (Left), severely impaired E/e′ ratio of 42 (Middle), and marked systolic blunting of pulmonary vein flow (Right).

• 

  Figure 3. Left Atrial Strain Evaluation Showing Marked Impairment of Reservoir Function (6%)

• 

  Figure 4. Right Ventricular Strain Analysis Showing Reduced Free Wall Strain Values (12.8%)

• 

  Figure 5. Hemodynamic Evaluation of Pericardial Effusion Mitral (Left) and tricuspid (Right) inflow pattern showing only modest respiratory variation, not suggestive of tamponade physiology.

• 

  Figure 6. Epicardial Mass (White Arrows) Appears Markedly Hyperintense on PSIR Sequences for Late Gadolinium Enhancement Assessment PSIR = phase-sensitive inversion recovery.

• 

  Figure 7. Epicardial Lesion Shown Encasing the Right Coronary Artery (White Arrow) Moderate pericardial effusion is also visible.

• 

  Figure 8. Circumferential Epicardial Mass (White Arrows) Showing a Very High Estimated Extracellular Volume Fraction (95%) Findings were compatible with a localized extracellular matrix deposition referred to as “amyloidoma.”

• 

  Figure 9. Histological Images From the Biopsy of the Epicardial Mass (A) Low-power hematoxylin and eosin stain demonstrating extensive extracellular eosinophilic amyloid deposition, representing the predominant component of the lesion, with an associated lymphoplasmacytic infiltrate. (B) Higher-power view of the boxed area in (A), highlighting the interface between the amyloid-rich area (left) and the lymphoplasmacytic infiltrate (right). Original objective magnification ×4 (A) and ×10 (B).