title: Malignant pheochromocytomas and paragangliomas: a diagnostic challenge.
abstract: BACKGROUND
  Malignant pheochromocytomas (PCCs) and paragangliomas (PGLs) are rare disorders arising from the adrenal gland, from the glomera along parasympathetic nerves or from paraganglia along the sympathetic trunk. According to the WHO classification, malignancy of PCCs and PGLs is defined by the presence of metastases at non-chromaffin sites distant from that of the primary tumor and not by local invasion. The overall prognosis of metastasized PCCs/PGLs is poor. Surgery offers currently the only change of cure. Preferably, the discrimination between malignant and benign PCCs/PGLs should be made preoperatively.
  
  
  METHODS
  This review summarizes our current knowledge on how benign and malignant tumors can be distinguished.
  
  
  CONCLUSIONS
  Due to the rarity of malignant PCCs/PGLs and the obvious difficulties in distinguishing benign and malignant PCCs/PGLs, any patient with a PCC/PGL should be treated in a specialized center where a multidisciplinary setting with specialized teams consisting of radiologists, endocrinologist, oncologists, pathologists and surgeons is available. This would also facilitate future studies to address the existing diagnostic and/or therapeutic obstacles.
authors: Department of Surgery, County Council of Östergötland, Linköping, Sweden. oliver.gimm@liu.se
authors: Oliver
authors: O
authors: Gimm
authors: Catherine
authors: C
authors: DeMicco
authors: Aurel
authors: A
authors: Perren
authors: Francesco
authors: F
authors: Giammarile
authors: Martin K
authors: MK
authors: Walz
authors: Laurent
authors: L
authors: Brunaud
mesh_terms: D000310:Adrenal Gland Neoplasms / Q000175:diagnosis* / Q000401:mortality / Q000628:therapy; D000315:Adrenalectomy / Q000379:methods*; D000818:Animals; D001707:Biopsy, Needle; D017024:Chemotherapy, Adjuvant; D003937:Diagnosis, Differential; D003952:Diagnostic Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D009367:Neoplasm Staging; D010235:Paraganglioma / Q000175:diagnosis* / Q000401:mortality / Q000628:therapy; D010673:Pheochromocytoma / Q000175:diagnosis* / Q000401:mortality / Q000628:therapy; D011379:Prognosis; D018714:Radiotherapy, Adjuvant; D016019:Survival Analysis