Cyto-diagnosis of serous effusions : A combined approach to morphological features in papanicolaou and may-grunwald giemsa stained smears and a modified cell block technique

The identification of cells as either malignant or benign reactive mesothelial cells in serous effusions is an everyday diagnostic problem. It is mainly due to the bland morphological details of the cells, overlapping or overcrowding of cells, cell loss and changes due to the different laboratory processing methods. To evaluate the diagnostic efficacy of a combined approach of morphologic features in smears of pleural and peritoneal fluids stained by the Papanicolaou (Pap) and May Grunwald Giemsa (MGG) methods and by cell blocks prepared by a modified technique. Smears of 85 aspirated samples of pleural and ascitic fluid were examined in order to compare cellularity, crowding of cells, nuclear preservation, cytoplasmic preservation, blackground and ability to make a definite diagnosis on the specimens. All these features were assessed on 0-3+ scale and were statistically analyzed. The MGG method was found superior for cellularity, cytoplasmic preservation, background materials, ability to make a definite diagnosis and in preventing cell loss and cell crowding, while the pap method was found to be superior for nuclear preservation. The modified cell blocktechnique produced histologic sections of excellent quality. The combined method increased the diagnostic yield of malignancy from 17 to 21 and reduced the atypical cases from toto1. The sensitivity of cytodiagnosis of effusions can be significantly increased by using all the three methods on each specimen - smears processed by Pap & MGG method and cell blocks rather than by using only one of these techniques. The modified cell block technique is very simple and cost effective.