Cyto-logical Evaluation – Malignant Cells involves examining a sample of body fluid (such as pleural, peritoneal, cerebrospinal, or ascitic fluid) under a microscope to detect the presence of malignant (cancerous) cells. This test is often used to identify cancers that have spread (metastasized) to body cavities from primary sites, like lung cancer , breast cancer , or ovarian cancer .

The process typically includes the collection of fluid via procedures such as thoracentesis or paracentesis , followed by microscopic examination of the cells. If malignant cells are found, it can help confirm a diagnosis of cancer, determine its type, and assess the extent of the spread. Cytology of fluids is useful for diagnosing and monitoring cancers or other diseases affecting body cavities.