Interobserver variability associated with the MIB-1 labeling index: high levels suggest limited prognostic usefulness for patients with primary brain tumors.

摘要: BACKGROUND The use of the MIB-1 labeling index (LI) as a potential prognostic marker for patients with primary brain tumors is controversial. Many studies advocating its usefulness have suggested discrete LI cut-off values, above which significantly worse outcomes. However, interobserver variability associated previously calculation has not been reported despite fact that degree impacts clinical such values. METHODS MIB-1 LIs were calculated independently using standardized protocol by six pathologist observers 50 astrocytic gliomas varying grades. The level agreement was determined calculating kappa statistics pairwise comparisons values 2.5%, 5.0%, 8.0%, 11.0%, and 15.0%. Spearman rank correlation coefficients used to assess associations between observer LIs. RESULTS Although there general among pathologists regarding whether an given astroglial tumor low, moderate, or high based on analysis correlation, determination specific LIs. highest occurred value this ranging from 0.52 0.80. CONCLUSIONS The suggests proposed most likely are useful clinically predicting outcome individual tumors. Further prospective needed investigating ranges optimize agreement. Cancer 2001;92:2720–6. © 2001 American Society.