A rare case report of ectopic-adrenal paraganglioma with inferior vena cava infiltration. Case report and literature review.

INTRODUCTION AND IMPORTANCE: Phaeochromocytomas are neuroendocrine neoplasms arising from chromaffin cells of the adrenal medulla and are known as intra-adrenal paragangliomas. On the contrary, paragangliomas are non-epithelial neuroendocrine neoplasms that produce other peptide hormones such as norepinephrine, epinephrine, and dopamine. In a setting with limited resources, such a condition may result in inaccurate diagnosis and treatment, which may lose a patient life if left untreated. In addition, PPGLs present a surgical challenge to many surgeons who are not thoroughly prepared.

CASE PRESENTATION: We describe a case of extra-adrenal paraganglioma in a 27-year-old female who presented with symptoms of heartbeat awareness for almost a year and abdominal swelling for three months. Physical examination revealed a palpable mass around the umbilicus. Abdominal pelvic CT scan revealed a well-circumscribed mass in the central retroperitoneum displacing the IVC laterally and abdominal aorta medially with no invasion of surrounding structures. Results for pheochromocytoma workup showed elevated levels of 24-h urine Vanillylmandelic acid (VMA), and 24-h metanephrine excretion. Laparotomy through extended midline incision was done with successful excision of the tumor. The blood pressure, which was initially high normalized after surgery.

DISCUSSION: The diagnosis of a malignant EAP is commonly made based on recurrence and the development of metastasis to lymph nodes or to other organs. Our patient presented with similar symptoms as pheochromocytoma. Compared to the commonly stated 10 % risk for pheochromocytomas, people with EAPs have been observed to have a 20 % to 50 % incidence of malignancy. EAPs account for at least 15 % of adult and 30 % of pediatric pheochromocytomas and are frequently found in the Zuckerkandl organ. Pheochromocytoma symptoms may manifest asymptomatically in patients with EAPs, or they may occur because of compression of nearby tissues. Surgical excision of the tumor is always the best option in managing EAP.

CONCLUSION: Extra-adrenal paragangliomas can be successfully managed surgically, provided there is a multidisciplinary team, and the tumor location is well recognized and can reduce the chance of tumor metastasis.