Endocrine Abstracts

Introduction: PGs are rare neuroendocrine tumours (NETs), slowly growing, derived from the neural crest cells of the autonomous nervous system. Presenting symptoms are related to catecholamine hypersecretion or to mass effect. The optimal approach is dictated by size, symptoms and anatomical relationship of tumours with neurovascular structures.

Aim: To describe a patient with bilateral carotid body and mediastinal carotid body PGs.

Case report: A 35 years old hypertensive female, previously diagnosed with bilateral non-functioning carotid body PGs at 28 years of age. Family history was negative for NETs. She initially underwent a partial resection of the right carotid body tumour and histopathological analysis revealed PG. CT imaging also detected a left carotid tumour and a middle mediastinum tumour. Angiography demonstrated large, highly vascularized masses of the carotid artery bifurcation bilaterally (9×3.5 cm on the right, 3×5 cm on the left). The patient denied any symptoms related to catecholamine hypersecretion, mass effect at diagnosis. Biochemical and hormonal assessment was unremarkable. Three additional surgeries were performed, one on each tumour. Left transpleural partial resection of the mediastinal mass led to left vocal chord palsy. During follow-up, the right cervical and mediastinal PGs slowly enlarged. The right carotid tumour was irradiated externally (45 Gy) and remained stable in size. The mediastinal mass developed mass effects leading to cough, dyspnoea and chest pain. The patient underwent a complete tumour resection via a median sternotomy. A diagnosis of PG was confirmed histopathologically. The tumour cells stained positively for chromogranin and synaptophysin and the Ki67 index was 8%. The patient recovered uneventfully, is currently asymptomatic and being followed up. Despite an apparently sporadic presentation, genetic testing for PGL genes mutation including succinate dehydrogenase subunits is required, especially given multicentric disease at a young age.

Conclusions: Multiple cervical and mediastinal PGs are exceedingly rare. In these patients, initial diagnosis and management should be followed by close observation, in order to detect multicentric tumours. Multidisciplinary collaboration is required for improved outcomes.

Keywords: Sporadic paraganglioma, middle mediastinum, multiple paraganglioma