Paraganglioma of the pancreas: a potentially functional and malignant tumor.

Paragangliomas are neoplasms that arise from extra-adrenal chromaffin cells. Pancreatic paragangliomas are rare, and few are malignant. To the best of our knowledge, no cases of functional pancreatic paragangliomas have been reported in the literature to date. We present two cases of pancreatic paragangliomas with pathological confirmation. In the case 1, clinical testing and pathological analysis revealed functional and malignant characteristics of the tumor, which carried a poor prognosis. In case 2, functional paraganglioma was suspected. The clinical presentations and outcomes of these two patients are summarized, and the relevant literature is reviewed. Because of the small number of cases reported previously, few characteristics of these tumors are known. The best methods of predicting the malignant and functional potential of these tumors remain unknown. We propose careful preoperative treatment and close postoperative follow-up of paraganglioma patients because of the functional and malignant potential of these tumors.