Complementary value of DNA flow cytometry and image morphometry in detection of malignant cells in effusion fluids

In cytologic evaluation of body cavity effusions, the morphologic changes exhibited by reactive mesothelial cells often confound the diagnosis. This study investigates the role of DNA flow cytometry (DNA FCM) and image morphometry (IM) in improving diagnostic accuracy.

53 pleural and 47 ascitic fluid samples were evaluated cytologically. All were also subjected to flow cytometry to assess DNA ploidy. Image morphometry was used to measure nuclear diameter, nuclear perimeter and nuclear area.

On cytomorphology 79% cases were diagnosed as benign, 19% as malignant and 2% as suggestive of malignancy. DNA FCM showed aneuploidy in 13 of 19 malignant cases and diploidy in 6 cases. The mean nuclear area of the benign group was 60.14 ± 39.91 µm² and that of malignant cases was 190.54 ± 56.06 µm². Using DNA FCM and IM, one of the two cases "suggestive of malignancy" was placed in the benign group and the other in the malignant group. Also, these modalities were able to pick up one case of malignancy that was diagnosed as benign on cytology.

Cytomorphology remains the foremost diagnostic modality in detecting malignant cells in effusions. DNA flow cytometry and image morphometry hold a valuable complementary value.