Large Malignant Pheochromocytoma Causing Cardiac Failure and Metastasis: A Case Report With Review of Literature.

Extra-adrenal functional neuroendocrine neoplasms are termed paragangliomas. We describe a case of a large abdominal neuroendocrine tumor that was proved to be a paraganglioma on biopsy. Unfortunately, the patient presented with high output heart failure, an extremely rare complication of paraganglioma. Prior to surgical biopsy, the patient underwent a complete invasive and non-invasive cardiac workup, in addition to biochemical testing. On a PET CT, the retroperitoneal neuroendocrine tumor was shown to have been metastasized to the spine. Chemotherapy targeted at somatostatin analogs was initiated. The unique presentation and rare complications are presented with relevant review of literature to highlight the spectrum of disease geared towards diagnostic and interventional radiologists. It is crucial to understand the broad spectrum of disease and include this entity in the differential diagnosis of a retroperitoneal mass. Equally significant is to consider potential complications such as metastases and cardiac failure to guide appropriate workup and management.