A case of mistaken identity

Paragangliomas (PG) are rare tumors of the autonomic nervous system. Their origin takes part in the neural crest cells, which produce neuropeptides and catecholamines [1]. In 1050% of cases, they are hereditary, beginning at younger ages. In 80-90% of abdominal PG and 5-10% of head and neck PG, catecholamine production can cause arterial hypertension, headache, palpitations, anxiety and weight loss [1,2]. The diagnosis is usually made by conventional imaging (CT, MRI, scintigraphy). A biopsy cannot distinguish benign from malignant tumors (<10%), which can be diagnosed in the presence of distant metastasis [3]. On the other hand, biopsy of these lesions might be dangerous, with the possibility of causing a life threatening event [4]. The most sensitive and specific pre-operatory diagnostic test is the determination of plasma and urine metanephrines [5]. Histological examination showing polygonal cells with finely granular eosinophilic cytoplasm, oval nuclei and positivity for neuroendocrine markers such as cromogranine A, neuron-specific enolase, synaptophysin and insulin-like growth factor II are specific for paragangliomas and are not present in hepatocellular tumors [6]. The treatment for non-metastatic disease involves surgical resection [5]. It is also recommended that these patients must be tested for succinate dehydrogenase mutations.

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