Metastatic Carcinoid Tumor to Heart

A 78-year-old-Japanese man was admitted to hospital because of a cardiac tumor. He had undergone surgery for a thymic carcinoid tumor with capsular invasion at 68 years old, followed by radiation therapy. Since then, no heart abnormality had been found by ECG, chest X-ray, or transthoracic echocardiography (TTE). On this admission, chest X-ray showed cardiomegaly (Figure A), and ECG showed sinus rhythm and negative T waves in II, III, aVF, and V4–6 leads. TTE revealed a cardiac mass at the posterolateral wall and apex of the left ventricle (Figure B) without any valvular disease. Enhanced computed tomography confirmed the cardiac mass (Figure C) without any mass in other organs. Cardiac magnetic resonance imaging also showed the cardiac mass (Figure D) with both T2-weighted high intensity (Figure E) and gadolinium enhancement (Figure F). Laboratory data were normal, except for a high serum level of B-type natriuretic peptide (519 pg/mL). Urine 5-hydroxyindole acetic acid was 2.7 mg/day (normal range, 0.5–5.0).

Figure.

Chest X-ray shows cardiomegaly (A). Cardiac mass on transthoracic echocardiography (B, *) and chest computed tomography (C). Cardiac magnetic resonance images (D, T1-weighted; E, T2-weighted) shows the cardiac mass with gadolinium enhancement (F). Histopathology shows a carcinoid tumor (G, H&E; H, immunostaining for chromogranin A, I, neural cell adhesion molecule).

Endomyocardial biopsy was performed. Small cells with atypical nuclei were seen in the myocardium (Figure G) and were positive for chromogranin A (Figure H) and neural cell adhesion molecule (Figure I) by immunostaining. Finally, he was diagnosed with metastatic carcinoid tumor (MCT) to the heart. No treatment was decided at the meeting with oncologists and cardiac surgeons.

Although MCT is uncommon, we have to consider it even in cardiac tumor without carcinoid syndrome and carcinoid heart disease after surgical treatment of the primary carcinoid tumor.

Disclosures

K.M. is a member of Circulation Journal’s Editorial Team.

Conflicts of Interest

The authors have no conflicts of interest to declare.