MIB-1 proliferation index predicts survival among patients with grade II astrocytoma.
The purpose of this study was to determine whether a relationship existed between MIB-1 labeling index (LI) percentages and survival in patients with grade II astrocytomas. From archival paraffin-embedded surgical specimens of 50 patients of the University of Michigan Medical Center with World Health Organization grade II astrocytomas, 22 patients had a Ki-67 LI of less than or equal to 2.0; and 28 patients had a MIB-1 LI of more than 2.0. Over a median follow-up interval of 10 years, ranging up to 16 years, 23% (n = 5) died of tumor in the first group while 82% (n = 23) died in the second group, a distinct difference in survival between these groups. Univariate analysis showed that a high MIB-1 predicted shorter survival (p < 0.0001), and that increased age was associated with shorter survival (p = 0.007). Gender, tumor location and radiotherapy had no significant association with survival. When adjusting for these (excluding tumor location) in the Cox proportional hazards model simultaneously, MIB-1 and age were independently prognostic. The hazard ratios were 1.301 per 1% MIB-1 LI (p = 0.0001), and 1.045 per year of age (p = 0.0028). From other studies, we know that histopathologic grade and age predict survival for glioma patients. However, even within grade II astrocytomas there is still a wide heterogeneity in how long a patient survives. We conclude that among grade II astrocytomas older patients and, independently, patients with higher MIB-1 labeling index have shorter survival.
McKeever
P E
PE
Department of Pathology, University of Michigan, Ann Arbor, USA.
Strawderman
M S
MS
Yamini
B
B
Mikhail
A A
AA
Blaivas
M
M
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000704:Analysis of Variance; D000911:Antibodies, Monoclonal / Q000276:immunology; D001254:Astrocytoma / Q000473:pathology*; D001932:Brain Neoplasms / Q000473:pathology*; D002455:Cell Division / Q000187:drug effects; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007223:Infant; D019394:Ki-67 Antigen / Q000032:analysis* / Q000276:immunology; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D016019:Survival Analysis
D000911:Antibodies, Monoclonal; D019394:Ki-67 Antigen