A patient with a large recurrent pheochromocytoma demonstrating the pitfalls of diagnosis

Abstract

This Case Study illustrates some of the potential pitfalls of diagnosis and demonstrates a combination of problems of follow-up biochemical screening in a patient operated for a large pheochromocytoma at increased risk of malignant disease. The difficulty in assessing the presence of disease after initial surgical resection and reaching a diagnosis of malignancy are highlighted. Background. A 59-year-old man presented for a follow-up, 6 years after surgery for a large pheochromocytoma. He had suffered from diabetes mellitus, hypertension and abdominal pain in the right flank region. Previous postoperative follow-up did not reveal tumor recurrence. Investigation. Measurement of plasma free metanephrine and normetanephrine by high-performance liquid chromatography and radioimmunoassay; 123I-metaiodobenzylguanidine (MIBG) scintigraphy; hybrid 123I-MIBG single-photon emission CT (SPECT)–CT; MRI; testing for plasma norepinephrine and epinephrine; intraoperative ultrasonography; histological staining for chromogranin A and synaptophysin; and postoperative 18F-dihydroxyphenylalanine (DOPA) PET scan. Diagnosis. Recurrent pheochromocytoma. Management. Laparotomy with tumor resection. Reduction of antihypertensive medications. Further follow-up by MRI, hybrid 123I-MIBG SPECT–CT and testing for plasma catecholamines and free metanephrines.