A grading study of gliomas using computer aided malignancy classification and histologic morphometry

Abstract

Forty three cases of astrocytic tumors and mixed gliomas were studied with the aim of evaluating the reproducibility of the Kernohan grading system vis a vis (a) grading using computer-aided malignancy classifier TESTAST 268 and (b) grading by quantitative morphometric evaluation of the various histological parameters of TESTAST 268. These patients were then followed up for variable periods with a maximum of forty months. High inter and intra-observer variability were observed in the Kernohan grading system. TESTAST 268 was found to be simpler, rapid and more reproducible. However, one drawback observed of this system was that it did not completely eliminate inter-observer variability because there was still some subjectivity in assignment of the categorical values against the histological features. Morphometric evaluation of the semi-quantitative assignment values of the 4 histological variables in the TESTAST 268 classifier using Zeiss Morphomat-30 revealed a statistically significant difference between the clusters of the measured quantitative values. A repeat grading using TESTAST 268 and categorical assignment values of histological features derived from the absolute values obtained by morphometry resulted in complete elimination of inter-observer variability. Thus, this study highlights the importance of objectivisation using TESTAST 268 and histologic morphometry in the grading of gliomas. However, since this is a preliminary study on a small number of cases, no cut off values of these measurements have been proposed.

Morphology of angiogenesis in human cancer: a conceptual overview, histoprognostic perspective and significance of neoangiogenesis

“…The measurements so obtained when applied to semiquantitative feature assignment values of TESTAST were found to have statistically significant differences. 50 TESTAST is a computer-aided semiobjectivized grading system for astrocytic tumours and mixed gliomas, that uses three clinical variables, namely age, location and brainstem involvement, along with five histological variables, namely mitosis, necrosis, vascularization, endothelial proliferation and Rosenthal fibres, in order to reproduce the four-step Kernohan grading with the aid of Bayes and canonical linear discriminant analysis, and thus demonstrated high reproducibility. 51 The TESTAST grades so obtained when combined with BrdU labelling indices could subdivide glioblastomas into prognostically different groups.…”

A comparative survival evaluation and assessment of interclassification concordance in adult supratentorial astrocytic tumors

“…Morphometric quantitation 18 eliminates the uncertainty of semi-objectiveness but is very labour intensive and thus may not be routinely applicable in classical situations. WHO typing 9 is fairly reproducible but the drawback is the absence of any clearly objectivized histological criteria.…”

Primary brain tumors: Proton magnetic resonance spectroscopic analysis and histopathological correlation

“…Metastatik tümörler dışındaki beyin tümörlerinden oluşan primer beyin tümörlerinin insidansı her geçen gün biraz daha artmaktadır [1]. Primer beyin tümörlerinin tedavisinde son zamanlarda kaydedilen gelişmeler; tümörün tanısı yanısıra tedavi etkinliğinin de değerlenmesi açısından radyolojik görüntüleme yöntemlerine olan ilgiyi arttırmıştır [2].…”