Use of Digital Slide Imaging for the Establishment of a Quantitative Database of Meningioma Cellularity
Cameron Dowlatshahi, Rajyasree Emmadi, Kitti Brinyiczki, Tibor Valyi-Nagy. University of Ilinois Hospital and Health Sciences System, Chicago, IL
Background: The grading of meningiomas includes some subjective criteria such as the determination of the presence or absence of increased cellularity. No firm objective and quantitative criteria have been established to guide pathologists in this task. The objective of this study is to establish a quantitative database of meningioma cellularity that can be used as a reference for more objective meningioma grading.
Design: To establish a quantitative database of meningioma cellularity, 205 meningiomas diagnosed at our Institution between January 2006 and August 2012 were identified for this study. Cases included 137 WHO grade I, 66 WHO grade II, and 2 WHO grade III meningiomas. Hematoxylin and eosin-stained sections of all cases are scanned using a Hamamatsu Nanozoomer 2.0 HT digital slide scanner. Digitalized whole slide images are reviewed by two independent observers and two 0.16 square millimeter areas of each tumor demonstrating the highest cellularity are selected and assessed for the number of meningioma cells by manual counting. Tumor cell counts generated by the independent observers are included into the determination of the cellularity of each case and based on these measurements, the mean, median, range and standard deviation of the cellularity of the studied reference meningioma set will be determined.
Results: Ten meningiomas have so far been assessed for cellularity in this ongoing study. Observations collected so far indicate mean and median meningioma cellularity of 964 and 968 tumor cells per 0.16 square millimeters, respectively, with a standard deviation (SD) of means of 193 and a range of 689 to 1253 (n=10). The measurements for different grades of meningioma were: (i) for WHO grade I meningiomas (n=5): mean= 837, SD of means=130, median=780, range= 689 to 993; and (ii) for WHO grade II meningiomas (n=4): mean= 1077, SD of means=176, median=1097, range=862 to 1253. Cellularity of the single case of WHO grade III meningioma analyzed so far was 1143 per 0.16 square millimeters.
Conclusions: Our initial observations indicate that determination of meningioma cellularity is feasible with the use of digital slide imaging. When completed, this study will establish a quantitative database of meningioma cellularity that will be a useful and practical reference tool for a more objective meningioma grading.
Wednesday, March 6, 2013 9:30 AM
Poster Session V # 287, Wednesday Morning