A CASE OF MALIGNANT PHEOCHROMOCYTOMA WITH A GIANT GROWTH

Abstract

It is said that malignant pheochromocytomas represent about 10% of all pheochromocytomas, and no effective treatment has been established for malignant pheochromocytoma if it is associated with multiple organ metastases before surgery. We experienced a rare case of giant malignant pheochromocytoma with coexistence of poorly differentiated neuroendocrine tumor and its hepatic metastasis. A 37-year-old man was seen at the hospital because of left lateroabdominal pain. At initial visit, a giant tumor 17cm in diameter was noted in the retroperitoneum. The patient also had attacks of hypertension. With close examination, the tumor was diagnosed as pheochromocytoma. Besides the tumor, scattered tumors were observed in the liver, indicating malignant pheochromocytoma. The tumor was extirpated. Histopathologic examination of the specimen revealed malignant pheochromocytoma with coexistence of poorly differentiated neuroendocrine tumors. Only poorly differentiated neuroendocrine tumors occurred in the hepatic metastatic foci. Although the origin of pheochromocytoma is still obscure, here we report this valuable case of malignant pheochromocytoma with neuroendocrine tumors which may be involved in the genesis of the disease.