title: Radiographic Characteristics of Adrenal Masses in Oncologic Patients.
abstract: BACKGROUND
  We aimed to assess the usefulness of pre-contrast Hounsfield unit (HU) and mass size on computed tomography to differentiate adrenal mass found incidentally in oncologic patients.
  
  
  METHODS
  From 2000 to 2012, 131 oncologic patients with adrenal incidentaloma were reviewed retrospectively. Receiver operating characteristic (ROC) curves were applied to determine the optimal cut-off value of the mean HU and size for detecting adrenal metastasis.
  
  
  RESULTS
  The median age was 18 years, and 80 patients were male. The initial mass size was 18 mm, and 71 (54.2%) of these were on the left side. A bilateral adrenal mass was found in 11 patients (8.4%). Biochemically functional masses were observed in 9.2% of patients. Thirty-six out of 119 patients with nonfunctional masses underwent adrenalectomy, which revealed metastasis in 13. The primary cancers were lung cancer (n=4), renal cell carcinoma (n=2), lymphoma (n=2), hepatocellular carcinoma (n=2), breast cancer (n=1), and others (n=2). The area under the curve for the size and HU for clinically suspicious metastasis were 0.839 (95% confidence interval [CI], 0.761 to 0.900; P<0.001) and 0.959 (95% CI, 0.898 to 0.988; P<0.001), respectively. The cut-off value to distinguish between metastasis and benign masses were 22 mm for size and 20 for HU.
  
  
  CONCLUSIONS
  ROC curve results suggest that pre-contrast HU >20 can be used as a diagnostic reference to suggest metastasis in oncologic patients with adrenal masses.
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Ji Hyun
authors.initials: JH
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Eun Ky
authors.initials: EK
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: A Ram
authors.initials: AR
authors.lastname: Hong
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Eun
authors.initials: E
authors.lastname: Roh
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Jae Hyun
authors.initials: JH
authors.lastname: Bae
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Jung Hee
authors.initials: JH
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Chan Soo
authors.initials: CS
authors.lastname: Shin
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Seong Yeon
authors.initials: SY
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.|Department of Internal Medicine, Seoul Metropolitan Government Seoul National University Boramae Medical Center, Seoul National University College of Medicine, Seoul, Korea. swkimmd@snu.ac.kr.
authors.forename: Sang Wan
authors.identifier: http://orcid.org/0000-0001-9561-9110
authors.initials: SW
authors.lastname: Kim
keywords: Adrenal incidentaloma; Metastasis; Neoplasms