Nonfunctional Retroperitoneal Paraganglioma: A Histopathological Surprise

Paragangliomas are the tumors arising from chromaffin tissue which is distributed along the autonomic nervous system. Most of these tumors secrete and store catecholamines. They can be suspected by clinical symptoms and confirmed by biochemical tests. Retroperitoneal paraganglioma mostly arise from adrenal medulla and are also known as adrenal pheochromocytoma. About 10% of abdominal paragangliomas occur at extraadrenal locations and where they are known as extraadrenal paraganglioma or pheochromocytoma (EAP). Like their adrenal counterparts, most EAPs are functional tumors as they secrete and store catecholamines. Very few EAPs do not secrete clinically detectable amount of hormones and present themselves with the pressure symptoms related to their size. These nonfunctional EAPs mimic more commonly occurring tumors of the retroperitoneum and true diagnosis is made only after microscopic examination of the tumor tissue. We had a patient who was suspected to have a pancreatic tumor but found to have a nonfunctional primary EAP completely separate from the pancreas.