Pheochromocytoma: Study of 50 cases

Purpose: We studied the clinical picture, sensitivity of the biochemical tests and imaging studies, pathological findings, surgical results and followup of patients with pheochromocytoma. Materials and Methods: The records of 50 patients with pheochromocytoma were identified. Hyperadrenergic symptoms and signs; urinary dopamine, epinephrine, norepinephrine and vanillylmandelic acid levels; serum dopamine, epinephrine and norepinephrine levels; ultrasonography; computerized tomography; magnetic resonance imaging and (131)iodine-metaiodobenzylguanidine images were analyzed. The size, weight and malignancy of the tumors, as well as the operative mortality, survival rate and clinical condition of the patients were also studied. Results: The hyperadrenergic syndrome alone was found in 90% of the patients, Cushing's syndrome alone in 2%, both syndromes in 4%, a palpable abdominal tumor only in 2% and incidental tumors in 2%. The sensitivities of the urinary evaluation in the diagnosis were metanephrines 97%, vanillylmandelic acid 90%, epinephrine 64%, norepinephrine 93% and dopamine 66%. For serum assessment the sensitivities were epinephrine 67%, norepinephrine 93% and dopamine 63%. The sensitivities of the localization examinations were 89, 94, 100 and 88% for ultrasonography, computerized tomography, magnetic resonance imaging and I-131-metaiodobenzylquanidine, respectively. There was only 1 operative death. Of the patients with benign tumors 88% were cured and 12% remained hypertensive with no clinical or biochemical evidence of a hyperadrenergic profile. Of the 8 patients with malignant pheochromocytoma 1 was lost to followup and 3 died of widespread disease (1 without surgery and at 2, 24 and 78 months postoperatively). Of the 4 living patients 3 had no evidence of disease and 1 was well, although with pulmonary metastases.