PHEOCHROMOCYTOMA AND SECONDARY ERYTHROCYTOSIS - ROLE OF TUMOR ERYTHROPOIETIN SECRETION

Certain neoplasias can induce unregulated erythropoietin (EPO) secreti on which results in secondary erythrocytosis, Pheochromocytoma associa ted with erythrocytosis constitute a rare condition, where the seconda ry red cell abnormality is believed to be due to tumour EPO secretion. In one such case of pheochromocytoma related erythrocytosis, quantita tive determination of serum EPO by enzyme immunoassay was combined wit h immunohistochemical examination of tumour tissue sections to locate the site of EPO secretion. EPO levels were initially high but decrease d after tumour surgery, while immunolocalization showed EPO to be secr eted by the neoplastic cells.