RESUMO
PURPOSE: We underwent this study to evaluate the diagnostic potential of I-123/I-131 metaiodobenzylguanidine (MIBG) scintigraphy alone in the initial diagnosis of pheochromocytoma, compared with biochemical test and anatomic imaging. MATERIALS & METHODS: Twenty two patients (M:F=13:9, Age: 44.3+/- 19.3 years) having the clinical evaluation due to suspicious pheochromocytoma received the biochemical test, anatomic imaging modality (CT and/or MRI) and I-123/I-131 MIBG scan for diagnosis of pheochromocytoma, prior to histopathological confirmation. MIBG scans were independently reviewed by 2 nuclear medicine physicians. RESULTS: All patients were confirmed histopathologically by operation or biopsy (incisional or excisonal). In comparison of final diagnosis and findings of each diagnostic modality, the sensitivities of the biochemical test, anatomic imaging, and MIBG scan were 88.9%, 55.6%, and 88.9%, respectively. And the specificities of the biochemical test, anatomic imaging, and MIBG scan also were 69.2%, 69.2%, and 92.3%, respectively. MIBG scan showed one false positive (neuroblastoma) and one false negative finding. There was one patient with positive MIBG scan and negative findings of the biochemical test, anatomic imaging. CONCLUSION: Our data suggest that I-123/I-131 MIBG scan has higher sensitivity, specificity, positive predictive value, negative predictive value and accuracy than those of biochemical test and anatomic imaging. Thus, we expect that MIBG scan is e tectively used for initial diagnosis of pheochromocytoma alone as well as biochemical test and anatomic imaging.
Assuntos
Humanos , 3-Iodobenzilguanidina , Biópsia , Medicina Nuclear , Feocromocitoma , Sensibilidade e EspecificidadeRESUMO
Pheochromocytoma is an uncommon tumor that originates in the adrenal medulla or in other paraganglia of the sympathetic nervous system. If a hypertensive crisis occurs during general anesthesia in incidental or untreated pheochromocytoma, it is a life-threatening event with a mortality rate of about 80%. Anesthetic drugs such as pancuronium, atracurium, and metoclopromide can exacerbate the potentially lethal cardiovascular effects of catecholamines. We report a case of a patient with pheochromocytoma who display abrupt increases in systolic arterial pressure and plasma norepinephrine following rocuronium administration. This case indicates the possible involvement of elevated sympathetic nervous system to a catecholamine crisis triggered by rocuronium in pheochromocytoma.