Congress logo
Back to Conference page

UICC World Cancer Congress 2006

Bridging the Gap: Transforming Knowledge into Action

July 8-12, 2006, Washington, DC, USA

Monday, 10 July 2006 - 12:00 PM
84-114

Diagnosis and Prognosis of Glioblastoma Multiforme Utilizing MCM7 and Ki-67 as Tumor Proliferation Markers

Matthew S. Sinnwell, BS, Department of Pathology, University of Iowa Carver College of Medicine, 100 Medical Research Center, Room 260 MRC, Iowa City, IA 52242, Pifu Luo, MD, PhD, Department of Pathology, University of Iowa, 100 Medical Research Center, Room 263 MRC, Iowa City, IA 52242, and M. Bridget Zimmerman, MS, PhD, Department of Biostatistics, University of Iowa, C22E - General Hospital, Iowa City, IA 52242.

Objective: Proliferation marker Ki-67 is recommended but rarely used in diagnosis and evaluation of GBM. Recent studies have indicated over-expression of minichromosome maintenance proteins (MCM) in multiple cancer types. The purpose of this study is to quantify and compare MCM7 and Ki-67 in GBM to determine if a correlation exists between positive stained cells and patient prognosis.

Methods: MCM7 and Ki-67 were evaluated using an immunohistochemical method. Blocks of 86 GBM cases were archived from two institutions. Slides were immunostained with anti-MCM7 and anti-Ki-67 antibodies. MCM7 and Ki-67 labeling indices were quantified based upon counting positive stained cells per 500-3000 tumor cells in each case. Statistical analyses were performed using Cox proportional hazards analysis methods, Kaplan-Meier curves, and log rank tests.

Results: Indices of Ki-67 and MCM7 were 26.50 ± 14.03 and 45.02 ± 21.36 in these cases (n=86). Both indices were strongly correlated (r=0.79, p<0.0001), but MCM7 index was consistently higher than Ki-67. Both proliferation markers correlated with patient prognosis, in that there were significant survival differences for patients with an MCM7 index cutoff of 25% (p= 0.025), and a Ki-67 index cutoff of 15% (p= 0.017). Ki-67 index was <15% in some GBM cases, but MCM7 index was >25% in those cases. In 11 cases, both indices were less than cutoffs (Ki-67, 15%; MCM7, 25%). The survival in those patients was longer. Results suggest both Ki-67 and MCM7 indices are useful and should be used in GBM diagnosis and survival prediction, and MCM7 index is a superior marker.


See more of Cancer Research, Detection and Treatment
See more of Cancer Research, Detection and Treatment

See more of The UICC World Cancer Congress 2006