title: Proposal for modification of the ENSAT staging system for adrenocortical carcinoma using tumor grade.
abstract: OBJECTIVE
  Various staging systems for adrenocortical carcinoma (ACC) have been proposed. We hypothesized that incorporating tumor grade into the current European Network for the Study of Adrenal Tumors (ENSAT) staging system would improve the ability to more accurately predict time to recurrence and death.
  
  
  METHODS
  A retrospective review of patients included in the University of Michigan ACC database from 2005 to 2009 was done; and stage, tumor grade, time to recurrence, and death were recorded and analyzed using the Cox regression and Kaplan-Meier survival curves.
  
  
  RESULTS
  Ninety one patients had complete information for inclusion. The median follow-up was 24 months while the median time to recurrence was 4.1 months. There were 28 deaths; overall, tumor grade showed a significant difference in time to tumor recurrence (p = 0.011) and time to death (p = 0.004). Time to death among stage 2 patients separated into those with high- and low-grade tumors reached statistical significance (p = 0.05), and notable but not statistically significant differences were identified in all stages. Based on tumor grade and survival curves, modifications to the current ENSAT staging system were made.
  
  
  CONCLUSIONS
  Tumor grade plays a significant role in the outcome of patients with ACC. High-grade tumors are associated with shorter disease-free intervals and shorter overall survival. The proposed modification of the ENSAT staging system allows for incorporation of tumor grade when predicting overall survival.
authors.affiliation: Division of Endocrine Surgery, University of Michigan, Ann Arbor, MI, USA. barbram@umich.edu
authors.forename: Barbra S
authors.initials: BS
authors.lastname: Miller
authors.forename: Paul G
authors.initials: PG
authors.lastname: Gauger
authors.forename: Gary D
authors.initials: GD
authors.lastname: Hammer
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Giordano
authors.forename: Gerard M
authors.initials: GM
authors.lastname: Doherty
mesh_terms: D000293:Adolescent; D000306:Adrenal Cortex Neoplasms / Q000401:mortality* / Q000473:pathology* / Q000601:surgery; D000315:Adrenalectomy / Q000379:methods; D018268:Adrenocortical Carcinoma / Q000401:mortality* / Q000473:pathology* / Q000601:surgery; D000328:Adult; D000368:Aged; D001707:Biopsy, Needle; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D005544:Forecasting; D006801:Humans; D007150:Immunohistochemistry; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000401:mortality* / Q000473:pathology / Q000601:surgery; D009367:Neoplasm Staging / Q000379:methods / Q000639:trends*; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D018709:Statistics, Nonparametric; D016019:Survival Analysis; D013997:Time Factors; D016896:Treatment Outcome; D055815:Young Adult