Unresectable cardiac paraganglioma – a rare case of clinically malignant tumor in an 8-year-old girl

Neurogenic tumors localized within the mediastinum are very rare and occur almost exclusively in the middle and posterior mediastinum. They tend to occur in older individuals (mean age: 46 years), predominantly in women [1, 2]. Patients are usually asymptomatic, or present with local malignancy (compression syndromes). About 50% of patients have arterial hypertension and other symptoms related to release of catecholamines by the tumor. If resection of the tumor is feasible, a 50% recurrence rate is reported; it metastases in about 25% of cases [3]. Very rare paragangliomas arise from cardiac tissue and are usually located subepicardially, at the roof of the left atrium. Here, we describe a case of paraganglioma in an 8-year-old girl located in the area of the left coronary artery origin and bifurcation. Prior to diagnosis, the symptoms of tumor had been misdiagnosed and treated as bronchial asthma. An 8-year-old girl with a non-characteristic medical history of shortness of breath, fatigability, exertional dyspnea and tachycardia as well as chest tightness was referred to the family doctor. Symptoms occurred irregularly and were not always present after physical effort. The family doctor carried out physical examination and laboratory tests (blood gases, blood morphology). The results of physical examination, and basic biochemical and hematological tests were unremarkable, apart from mild anemia (Table I). Screening echocardiography revealed good function of the ventricles and valves and no structural heart defect. Electrocardiography showed normal sinus rhythm with no characteristic changes. She was referred to the department of pediatric cardiology. Based on initial symptoms and known clinical results the hypotheses of cardiac disease, respiratory problems and endocrine disturbances were taken into account. Detailed echocardiography as well as magnetic resonance imaging (MRI), angio-computed tomography (angioCT) scans and ultrasound examination of the neck and abdomen was carried out. Accessory biochemical tests were performed to differentiate clinical symptoms. These included: indicators of heart ischemia (CKMB, hsTnT), heart failure markers (NT-proBNP), markers of germinal tumors (AFP – α-fetoprotein, β-HCG) and urine catecholamine metabolites concentration (Tables II, III). Ultrasound of the thyroid gland showed normal echogenicity of the gland with a regular pattern of vascularity. The size of the thyroid gland was within normal limits. The lymph nodes of the submandibular area were slightly enlarged. Ultrasonography of the abdomen demonstrated normal appearing liver without evidence of intrahepatic biliary dilatation. The gallbladder was normal in appearance without evidence of stones or wall thickening. The common bile duct was not abnormally distended. The head, body, and proximal tail of the pancreas were normal. The spleen was not enlarged. The kidneys were normal in size and echogenicity. No signs of collecting system dilatation were noted. There was no free fluid within the abdomen. The abdominal aorta and IVC were normal in caliber. Detailed echocardiography revealed presence of a tumor in the area of the origin of the left main coronary artery and its division into the left anterior descendant and