Role of DNA flow cytometry and image cytometry on effusion fluid

The objective of the study was to assess the value of DNA flow cytometry (F CM) and image cytometry (ICM) as an adjunct to routine diagnostic cytology. In this prospective study, 100 consecutive effusion fluids were studied fo r routine cytology, DNA FCM, and in selected cases, ICM. One half of the ce ntrifuged fluid sample was used for routine cytology and the remaining port ion was used for DNA FCM. Nuclear area, nuclear diameter, nuclear perimeter ; nuclear convex perimeter; nuclear roundess, and nuclear convex area were measured on at least 100 cells by ICM in cytologically malignant or DNA ane uploid cases along with control cases. Clinical follow-up was done in all c ases. There were 22 cytologically malignant cases and 78 cytologically beni gn cases. Among the 22 cytologically malignant cases, there were II aneuplo id and diploid cases each br DNA FCM. Out of 78 cytologically benign cases, sh (7.7%) were aneuploid by DNA FCM. Smears of these cases showed predomin antly reactive mesothelial cells, but the DNA histograms showed hypodiploid (one), hyperdiploid (three), tetraploid (one), and hypertetraploid (one) a neuploidy. Follow-up of these cases showed clinical or histologic features of malignancy except in one case of tetraploid aneuploidy, which did not sh ow any features of malignancy and responded well to antitubercular therapy. Therefore, out of 27 malignant effusions, DNA FCM picked up 16 cases and r outine cytology detected 22 cases. Sensitivity and specificity of DNA FCM w ere thus 59.25% and 98.63%, respectively. There was a statistically signifi cant difference (Student's unpaired t-test, P < 0.05) between cytologically malignant cases and control benign cases in all the nuclear morphometric p arameters except for nuclear roundness. There was, however, no statisticall y significant difference of nuclear morphometric parameters between cytolog ically benign vs. DNA aneuploid cases and control benign cases. DNA FCM is a useful adjunct for routine diagnostic cytology. Visual diagnostic cytolog y and morphometric digital microscopy miss some cases of malignancy which c an be detected by DNA flow cytometry. Diagn. Cytopathol. 2000;22:81-85. (C) 2000 Wiley-Liss, Inc.