Cytology is simply the study of cells . In cancer diagnosis, the term cytological studies means the examination of cellular material removed from the body. The cells might be removed by natural means, such as coughing up sputum (phlegm). They might also be removed by washing a body cavity with a salt solution—the inside of the abdomen after abdominal surgery, for example—or by scraping the surface of an organ or a suspected cancer.
The best-known cytological test is the one developed by George Papanicolaou—the Pap smear. The cervix is scraped and brushed to remove for analysis cells that could be abnormal or cancerous. In the same way, the tongue, esophagus, stomach or the lung's air passages can be easily scraped using a small brush through a scope.
The removed cells are put on slides, stained with dyes and examined under a microscope. The cytologist will look for the characteristic appearance of malignant or premalignant cells. A pathologist will also examine the slides and either diagnose cancer or report a strong suspicion of cancer. In many cases, a conventional surgical biopsy will usually be done to confirm the diagnosis.
Tumor Tests Several new techniques for cell analysis have been developed recently. These techniques improve doctors' ability to diagnose cancer, help determine the likely clinical course and help guide the choice of treatment options.
• Special stains. There are now a large number of special ways to stain cancer tissue in the laboratory. These stains are often of great help in determining the type of cancer when there is some uncertainty.
