Normotensive functional para-aortic paraganglioma: A rare case report with surgical and histopathological correlation

Abstract

INTRODUCTION: Paragangliomas are rare neuroendocrine tumors originating from extra-adrenal chromaffin tissue. Their clinical manifestations are variable, often depending on the tumor's size, location, and catecholamine secretion. While most functional paragangliomas present with hypertension, a small subset can remain normotensive, making diagnosis more challenging. CASE PRESENTATION: We report the case of a 45-year-old woman with no notable medical history, who presented with vague abdominal discomfort and episodic palpitations. Notably, she exhibited no documented hypertension. Biochemical evaluation revealed markedly elevated urinary normetanephrines. Cross-sectional imaging identified a 4.5 cm para-aortic mass, which was further confirmed by ^123I-MIBG scintigraphy. After adequate preoperative alpha- and beta-blockade, she underwent open surgical resection. Histopathological analysis confirmed paraganglioma, demonstrating characteristic zellballen architecture and immunohistochemical positivity for chromogranin A, synaptophysin, and S100. Her postoperative recovery was uneventful. At 12-month follow-up, she remained asymptomatic with normal catecholamine levels and no signs of recurrence. Genetic testing was offered but declined. CLINICAL DISCUSSION: This case emphasizes the diagnostic difficulty posed by normotensive functional paragangliomas, which may be overlooked in the absence of classical hypertension. Biochemical screening and functional imaging are crucial even in atypical presentations. Preoperative pharmacologic preparation and expert surgical management are key to minimizing intraoperative risk and ensuring favorable outcomes. CONCLUSION: Clinicians should maintain a high index of suspicion for paragangliomas in patients with suggestive symptoms, regardless of blood pressure status. A multidisciplinary approach and long-term follow-up are vital, particularly for extra-adrenal tumors, with consideration of genetic counselling in all cases.