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Malignant pheochromocytoma with negative biochemical markers: Is it time to reclassify pheochromocytomas?
Shiva Borzouei1, Seyed Habibollah Mousavi-Bahar2, Sayed Ahmadreza Salimbahrami3
1Clinical Research Development Unit of Shahid Beheshti Hospital, Hamadan University of Medical Science, Hamadan, Iran.
Abstract:
Pheochromocytomas are catecholamine producing tumors of adrenal gland generally diagnosed by presence of these markers in urine or plasma. However, a few may be marker-negative and challenging for clinicians. Several reports of these marker-negative pheochromocytomas may warrant necessity for a new classification of these tumors. Adrenergic blockade before surgery is one of the main reasons for recognition of these cases. We present a case of marker-negative pheochromocytoma which turned out to be malignant on its recurrence. To our knowledge, this is the only case of malignant marker-negative pheochromocytoma reported in literature so far.
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