title: Contrast-enhanced sonography of adrenal masses: differentiation of adenomas and nonadenomatous lesions.
abstract: OBJECTIVE
  The aim of this proof-of-principle study was to evaluate contrast-enhanced sonography in the characterization of adrenal masses.
  
  
  METHODS
  Thirty-five consecutively registered patients with newly detected adrenal masses underwent hormonal evaluation and duplex and Doppler sonography followed by contrast-enhanced sonography and CT or MRI. The dynamics of contrast enhancement were analyzed with time-intensity curves. CT and MRI were used as the reference methods for the diagnosis of adenoma and myelolipoma. Metastasis was diagnosed with fine-needle biopsy, and all other adrenal masses were diagnosed at adrenalectomy. Fisher's exact test was used to evaluate the criteria for diagnosis of malignant adrenal masses.
  
  
  RESULTS
  Size greater than 4 cm and hypervascularization were found significantly more often in malignant than in benign lesions (71% vs 21% for size; 57% vs 7% for hypervascularization). At contrast-enhanced sonography, early arterial or arterial contrast enhancement and rapid washout were seen in all patients with primary or secondary malignant lesions of the adrenal gland and in only 22% of patients with benign adrenal masses (p < 0.05). All primary malignant lesions were confirmed at histologic examination. In 32 of 35 patients (91%), findings at CT or MRI were congruent with those at contrast-enhanced sonography in regard to characterization of adenoma versus nonadenomatous lesion (p < 0.001). In two of the 35 cases, however, all imaging methods favored the diagnosis of nonadenomatous lesion, but the histologic result after adrenalectomy was adrenal adenoma. The sensitivity and specificity of contrast-enhanced sonography in the diagnosis of malignant adrenal mass were 100% and 82%.
  
  
  CONCLUSIONS
  Contrast-enhanced sonography can be used to differentiate adenomas and nonadenomatous lesions with a sensitivity comparable with that of CT and MRI and may be a cost-effective method for preselection of patients with adrenal masses.
authors.affiliation: Medizinische Klinik I, Klinikum der Johann Wolfgang Goethe Universität, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany.
authors.forename: Mireen
authors.initials: M
authors.lastname: Friedrich-Rust
authors.forename: Guenther
authors.initials: G
authors.lastname: Schneider
authors.forename: Rainer M
authors.initials: RM
authors.lastname: Bohle
authors.forename: Eva
authors.initials: E
authors.lastname: Herrmann
authors.forename: Christoph
authors.initials: C
authors.lastname: Sarrazin
authors.forename: Stefan
authors.initials: S
authors.lastname: Zeuzem
authors.forename: Joerg
authors.initials: J
authors.lastname: Bojunga
mesh_terms: D000236:Adenoma / Q000000981:diagnostic imaging*; D000310:Adrenal Gland Neoplasms / Q000000981:diagnostic imaging*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003287:Contrast Media; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010743:Phospholipids; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013459:Sulfur Hexafluoride; D014463:Ultrasonography
chemical_list: D003287:Contrast Media; D010743:Phospholipids; C420843:contrast agent BR1; D013459:Sulfur Hexafluoride