Dilated Cardiomyopathy in a Patient with a Primary Hepatic Neuroendocrine Carcinoma: A Case Report and Literature Review

Abstract

Introduction: Primary Hepatic Neuroendocrine Carcinoma (PHNEC) has an indolent natural history resulting in devastating clinical syndromes. PHNEC (CHD) has been reported in up to 70% of cases of carcinoid syndrome. Most common clinical presentations of CHD include right-sided valve lesions. We present a case of PHNEC with dilated cardiomyopathy and severe left ventricular dysfunction. To our knowledge, this association has never been reported. Case Report: A 56-year-old male presented for 2-3 weeks of dyspnea and abdominal discomfort. 2-D echocardiogram revealed that hypokinesis of the left ventricular with four chambers enlargement, mitral regurgitation, pulmonary hypertension, and tricuspid regurgitation. Catheterizarion revealed three-vessel coronary artery disease, aortic insufficiency, and left ventricular dysfunction with EF of 15-20%. CT abdomen showed a mass in the liver. Biopsy reported a neuroendocrine carcinoma. Urine 5-hydoxyubdikeacetic acid (HIAA) was 23 mg/day (normal: 0-15 mg/day). An octreotide scan revealed that demonstrated uptake only in the liver. The tumor was diagnosed as a PHNEC. The patient was treated with octreotide acetate. His medications also included aspirin, lisinopril, lasix, spironolactone, and carvedilol. Subsequent 2-D echocardiogram after treatment for 6 months revealed LV function to EF of 40%. Discussion: CHD is associated with deposition of fibrous tissue on the endocardical surface. Development is thought to relate to the vasoactive substance secreted, such as serotonin (5-HT), by the tumor cell in the liver reaching the right heart. Study shows that serotonin (5-HT) may increase synthesis and upregulate tissue growth factor β, as well as stimulating collagen synthesis by heart valve interstitial cells. Most common deposition of carcinoid plaque has been found in tricuspid valve. Left-sided lesions of CHD only occur in up to 15% of all cases since serotonin is inactivated as it passes through lung parenchyma. Involvement of left side may be due to the presence of right-to-left shunt, bronchial carcinoid, or high level of circulating vasoactive substances. PHNEC has a unique specificity during its occurrence; the pathogenesis of CHD with PHNEC remains incompletely understood. Conclusion: Dilated cardiomyopathy with severe left ventricular dysfunction in a patient with a primary hepatic neuroendocrine carcinoma has been rarely reported. Further need of reporting similar cases is required, which may provide us a better understanding of the etiology and the best treatment/prevention options for PHNEC and CHD.