Pathology: Examining Tissue for Signs of Cancer
When a polyp or other area of suspicious tissue is seen during a cancer screening test, the doctor may take a tissue sample — called a biopsy — right away, depending on the bodily location being examined, or at a later date, if doing so requires a second procedure. A pathologist then examines the tissue under a microscope to look for cancerous cells. To better visualize the various parts of the tissue, the pathologist often stains it, sometimes with multiple dyes. The pathologist looks for abnormalities in the shape and size of cells, shape and size of cell nuclei, and distribution of the cells in the tissue, indicating cancer. Once the pathologist has confirmed that a biopsy shows cancer, other lab tests may be done to help classify the cancer, which can in turn help to guide treatment. While much of the work of examining tissue samples is still done by individuals looking through microscopes, advances in automated detection and classification of cancer cells promise faster diagnosis and treatment. Surgery may involve removing a small tumor or polyp only, or removing a tumor and a portion of the surrounding tissue, if the tumor is larger or has spread into nearby tissue. The surgeon may also remove some lymph nodes near the area of cancer if it’s known the cancer has spread to them, or to see if the cancer has spread to them. Chemotherapy — drug therapy — may be used before surgery to shrink the size of tumors, or after surgery to kill any remaining cancer cells that may have spread to other parts of the body. Radiation therapy may similarly be given to shrink tumors before surgery or to kill any remaining cancer cells after surgery. It may also be used in place of surgery in some cases.
Prognosis: Disease Course Often Hard to Predict
In the United States, improved cancer screening and treatment have reduced the number of people who die from certain cancers, such as colon cancer. However, your chances of survival are generally decreased if a cancer has spread beyond its primary location. Malignant tumors can vary in their aggressiveness, so it is difficult to predict how rapidly they will grow. A medical oncologist can recommend appropriate testing and treatment to give you the best chance of survival.
