title: Adrenal incidentaloma, borderline elevations of urine or plasma metanephrine levels, and the "subclinical" pheochromocytoma.
abstract: OBJECTIVE
  To assess the risk of pheochromocytoma in patients with borderline-elevated urine or plasma metanephrine levels.
  
  
  METHODS
  Retrospective review.
  
  
  METHODS
  University tertiary care center.
  
  
  METHODS
  Forty-two consecutive patients with adrenal incidentalomas (defined as adrenal tumors identified during routine imaging for another condition) who were treated at the UCSF (University of California, San Francisco) Medical Center between January 1, 1995, and July 31, 2005. Patients with genetic syndromes were excluded.
  
  
  METHODS
  Laparoscopic adrenalectomy for adrenal incidentaloma based on size criteria and preoperative hormonal test results.
  
  
  METHODS
  Urine or plasma metanephrine and catecholamine levels, tumor size, and presence of pheochromocytoma.
  
  
  RESULTS
  Of 42 patients, 14 (33%) had a pheochromocytoma (11 of whom had clear-cut elevations in urine or plasma metanephrine levels defined as greater than 2 times the upper limit of normal) and 28 did not. Ten of the 42 patients (24%) had borderline elevations in urine or plasma metanephrine levels (defined as 1-2 times the upper limit of normal), 3 of whom had a pheochromocytoma (30%). Of patients with borderline elevations, mean +/- SD tumor size was 5.4 +/- 3.1 and 4.8 +/- 1.9 cm for patients with and without pheochromocytoma, respectively (P = .37). In these 10 patients, no clinical factors (age, sex, hypertension, presence of symptoms, number of antihypertensive medications, preoperative hemodynamics, or size of tumor on computed tomographic scan) allowed differentiation between those with and without pheochromocytoma.
  
  
  CONCLUSIONS
  Thirty percent of patients with adrenal incidentaloma and borderline-elevated urine or plasma metanephrine levels had a pheochromocytoma. Clinical factors cannot distinguish between those with and without pheochromocytoma. In this group of patients, we advocate either routine alpha-blockade preoperatively or further diagnostic tests to better characterize the tumor.
authors: Division of Gastrointestinal/Endocrine Surgery, Columbia University Medical Center, New York, New York, USA.
authors: James A
authors: JA
authors: Lee
authors: Rasa
authors: R
authors: Zarnegar
authors: Wen T
authors: WT
authors: Shen
authors: Electron
authors: E
authors: Kebebew
authors: Orlo H
authors: OH
authors: Clark
authors: Quan-Yang
authors: QY
authors: Duh
mesh_terms: D000310:Adrenal Gland Neoplasms / Q000097:blood* / Q000601:surgery / Q000652:urine*; D000315:Adrenalectomy / Q000379:methods; D016009:Chi-Square Distribution; D005260:Female; D006801:Humans; D033162:Incidental Findings; D010535:Laparoscopy; D008297:Male; D008676:Metanephrine / Q000097:blood* / Q000652:urine*; D010673:Pheochromocytoma / Q000097:blood* / Q000601:surgery / Q000652:urine*; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D016896:Treatment Outcome
chemical_list: D008676:Metanephrine