Stem cell therapy after irradiation of a malignant asecretory pheochromocytoma – a case report

A 51-year-old woman syncopated without tongue bit or enuresis. The day before she had felt a sudden pain in her right flank. Her medical and family history were inconspicuous. Physical examination, blood test, x-ray of the chest, 24-hour-ECG and 24-hour-BP-measurement were without pathological findings. Abdominal ultrasound revealed a mass at the right kidney. CT scan of the abdomen confirmed the presence of an approximately 8cm mass at the upper pole of the right kidney.

The patient was transferred for removal of a suspected carcinoma of the kidney. An endocrine evaluation revealed no abnormalities apart from slightly elevated urine metanephrines (1.4mg/24h; norm <1.0mg/24h). At open transperitoneal surgery a mass probably originating from the right adrenal and with adherence to the liver was resected. Histopathological examination showed a cystic, 10.5cm mass with medium-sized, pleomorphic cells with infiltration to capsule and adjacent fat tissue. Immunochemistry demonstrated a highly positive reaction for synaptophysin and chromogranine A. The diagnosis of a malignant pheochromocytoma was made. Postoperative MIBG-scintigraphy showed multiple metastases of liver, lung, brain, and bone. Chromogranine A and NSE were highly elevated (CgA 9.850µg/l, normal range <110µg/l; NSE 64.2µg/l, normal range <15.0µg/l). Sincethe patient did not suffer from hypertension and catecholamines were not elevated, no alpha-blockade was given. The patient was treated with two courses of 131I-MIGB (10.500 MBq each) leading to a pronounced decrease of CgA. Although the patient received autologue stem cell transplantation, persistent aplasia was developed leading to fungal pneumonia. The patient died of cerebral hemorrhage due to prolonged thrombocytopenia. Non-secreting malignant pheochromocytoma is a rare cause of adrenal incidentaloma. MIBG-therapy is usually well tolerated, but our patient suffered from severe aplasia probably due to bone marrow infiltration of MIGB-positive pheochromocytoma with consecutive irradiation of blood progenitor cells.