carcinoma in situ

Carcinoma in situ describes a cancer in the very earliest stage. At this point, the cancer is quite small and has not invaded the tissues beneath it.

 

Cancer develops in several stages. A cancer begins when a single cell becomes cancerous. This happens when the nucleus of a cell is damaged in such a way as to remove the normal growth control mechanisms of the cell. The cell then begins to grow and multiply out of control.

 

When enough of these cells are produced, they form a tumor. The tumor will eventually grow large enough to press on the tissue around it. The tumor will also invade and destroy the surrounding tissue.

 

When a tumor has formed but has not begun to invade tissue, it is said to be "in situ," which means in place. Some cancers may stay in this stage for a long time. Most cancers, however, do not stay in situ for long and begin to spread. Cancers found in situ are the easiest to cure because they have not spread.

 

Carcinoma in situ is so small that there may be no symptoms. Carcinoma in situ of the breast may be found when a small change is noted on a mammogram. Carcinoma in situ of the bladder may be found when the internal wall of the bladder is examined for other reasons. Routine Pap smears of the cervix are done to find carcinoma in situ of the cervix.

 

The risks for developing a particular type of carcinoma in situ are the same as the risks for developing that type of cancer.

Some cancers cannot be prevented. Other cancers, such as bladder cancer, lung cancer, and throat cancer, are related to smoking. Avoiding tobacco products in all forms may help prevent these cancers. For the cancers that cannot be prevented, finding the cancer in an early stage is very important to ensuring successful treatment. Routine breast self-exams, mammograms, Pap smears can help to find cancers in an early stage.

Carcinoma in situ is diagnosed by taking a sample, called a biopsy, of the area. This sample is sent to a laboratory to see if it is cancerous.