title: Pediatric adrenocortical neoplasms: can imaging reliably discriminate adenomas from carcinomas?
abstract: BACKGROUND
  There is a paucity of literature describing and comparing the imaging features of adrenocortical adenomas and carcinomas in children and adolescents.
  
  
  OBJECTIVE
  To document the CT and MRI features of adrenocortical neoplasms in a pediatric population and to determine whether imaging findings (other than metastatic disease) can distinguish adenomas from carcinomas.
  
  
  METHODS
  We searched institutional medical records to identify pediatric patients with adrenocortical neoplasms. Pre-treatment CT and MRI examinations were reviewed by two radiologists in consensus, and pertinent imaging findings were documented. We also recorded relevant histopathological, demographic, clinical follow-up and survival data. We used the Student's t-test and Wilcoxon rank sum test to compare parametric and nonparametric continuous data, and the Fisher exact test to compare proportions. We used receiver operating characteristic (ROC) curve analyses to evaluate the diagnostic performances of tumor diameter and volume for discriminating carcinoma from adenoma. A P-value ≤0.05 was considered statistically significant.
  
  
  RESULTS
  Among the adrenocortical lesions, 9 were adenomas, 15 were carcinomas, and 1 was of uncertain malignant potential. There were no differences in mean age, gender or sidedness between adenomas and carcinomas. Carcinomas were significantly larger than adenomas based on mean estimated volume (581 ml, range 16-2,101 vs. 54 ml, range 3-197 ml; P-value = 0.003; ROC area under the curve = 0.92) and mean maximum transverse plane diameter (9.9 cm, range 3.0-14.9 vs. 4.4 cm, range 1.9-8.2 cm; P-value = 0.0001; ROC area under the curve = 0.92). Carcinomas also were more heterogeneous than adenomas on post-contrast imaging (13/14 vs. 2/9; odds ratio [OR] = 45.5; P-value = 0.001). Six of 13 carcinomas and 1 of 8 adenomas contained calcification at CT (OR = 6.0; P-value = 0.17). Seven of 15 children with carcinomas exhibited metastatic disease at diagnosis, and three had inferior vena cava invasion. Median survival for carcinomas was 27 months.
  
  
  CONCLUSIONS
  In our experience, pediatric adrenocortical carcinomas are larger, more heterogeneous, and more often calcified than adenomas, although there is overlap in their imaging appearances.
authors: Section of Pediatric Radiology, C. S. Mott Children's Hospital, Department of Radiology, University of Michigan Health System, 1540 East Hospital Drive, Ann Arbor, MI, 48109, USA.
authors: Kelsey A
authors: KA
authors: Flynt
authors: Jonathan R
authors: JR
authors: Dillman
authors: Matthew S
authors: MS
authors: Davenport
authors: Ethan A
authors: EA
authors: Smith
authors: Tobias
authors: T
authors: Else
authors: Peter J
authors: PJ
authors: Strouse
authors: Elaine M
authors: EM
authors: Caoili
mesh_terms: D000293:Adolescent; D000302:Adrenal Cortex / Q000000981:diagnostic imaging / Q000473:pathology; D000306:Adrenal Cortex Neoplasms / Q000175:diagnosis*; D018246:Adrenocortical Adenoma / Q000175:diagnosis*; D018268:Adrenocortical Carcinoma / Q000175:diagnosis*; D002648:Child; D002675:Child, Preschool; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007223:Infant; D008279:Magnetic Resonance Imaging; D008297:Male; D015588:Observer Variation; D012372:ROC Curve; D015203:Reproducibility of Results; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed