6th ESACP Congress, Heidelberg, April 7-11, 1999

A091
IMAGE ANALYSIS OF FEULGEN-THIONIN STAINED NUCLEI WITH ROUND LOW-CHROMATIN AREAS (RLCA)
Lavrencak J*, Zganec M**, Us-Krasovec M*

*Institute of Oncology, Ljubljana, ** Faculty of Electrical Engineering, Ljubljana, Slovenia

Round low-chromatin areas (RLCA) have often been seen in the images of nuclei stained with Feulgen-thionin method. The RLCA may represent artefacts, nucleoli, viral infection changes or specific chromatin distribution in tumor cell nuclei. Our study was aimed to answer the following two questions; (i) do RLCA have any influence on the nuclear texture features and (ii) what is the percentage of nuclei with RLCA in a sample that can influence the results of nuclear texture features analysis. Five slides of HL60 cell line, 9 smears of normal human vocal cords and 19 smears of breast carcinoma were taken for image cytometry analysis. All the slides were air-dried and stained by Feulgen-thionin method. Image analysis was performed by Cyto-Savant (Oncometrics Imaging Corp., Vancouver, Canada). Probability density functions of 43 nuclear texture features, matched pairs t-test and simulation model were used for nuclear texture features analysis. Three nuclear texture features, namely rangeßextreme, fractalßarea and runßlength, were significantly affected in nuclei with RLCA. Previous studies showed that those three texture features had potential diagnostic or prognostic value. The results of simulation model indicated that mean values of those texture features increased by more than 10% if a sample contained more than 40% of nuclei with RLCA.