| Popis: |
The cell block preparation method is widely used in human cytopathology. In veterinary medicine, cytological examination of different effusions from the body cavities of dogs and cats is one of the most useful methods, especially when malignant process is suspected. Diagnostic challenges arise in everyday clinical practice, as it is difficult to differentiate reactive atypical mesothelial cells and malignant cells by the routine classical cytological examination. Instead of applying only conventional cytology, effusions can be further processed by using the cell block method, which may augment the diagnostic utility. Several techniques have been proposed to convert fluid specimens of different effusions into solid material. The aim of this study was to compare the diagnostic utility of classical cytological examination, cell blocks and their combination, regardless of the etiology of effusions. A total of 4 effusions in body cavities (from 2 dogs and 2 cats) were subjected to routine laboratory analysis. For classical examination, a minimum of two thin smears were prepared from the sediment, air dried and stained with the May-Grünwald-Giemsa stain. Cell blocks were prepared after fixation in 10% neutral buffered formalin, embedded in paraffin and sectioned on 4 and 5 µm using a microtome. Sections were stained with hematoxylin and eosin (H&E). The histomorphological features were examined using an Olympus BX41 microscope. The results of both methods were compared to the final diagnosis. When compared to the classical smear examination, the results obtained from the paraffin-embedded cell blocks yielded more cellularity and better architercural patterns, which led to more reliable diagnosis. As these are only preliminary results, a larger study is needed for higher efficiency of cell block method value. As far as it can be observed, cell block method is a diagnostic tool which is not yet used in the veterinary medicine in Croatia. Paraffin- embedded cell blocks can be used for additional staining and testing, such as histochemistry, immunohistochemistry and molecular diagnostics.Therefore, the cell block method could be considered a useful diagnostic tool in evaluating fluid specimens for a final cytodiagnosis, along with the classical smear examination of effusion. |
