This study was conducted with an aim to recognize different cytomorphological features of malignant cells in body fluids to facilitate the diagnosis and to locate primary site especially in clinically obscure cases. Fifty eight cases of malignant effusions from different serous cavities were analysed by examination of cytospin smears and cell block preparations taking detailed account of clinical and radiological data. Of the 58 cases, peritoneal, pleural and pericardial effusions accounted for 32, 25 cases and 1 case respectively. The maximum number of cases were in 51-60 years of age group (34.6%). Female patients outnumbered the males (56.9% Vs. 43.1%). Detailed cytomorphologic study of each type of malignant effusion revealed some very consistent features which helped in reaching the primary site. On correlating clinical, radiological and cytological features, primary site could be determined with 89.7% accuracy, while in 10.3% cases cytologic features were inconclusive and could not be associated with primary site. Lung (29.3% cases) was the commonest primary site, followed by ovaries (15.4%) and gastrointestinal tract (8.6%). It was also concluded that compared to the time and energy required for cell block preparation, cytospin was found a better method.

Key words : malignant effusions, cytology, primary site