Biopsies are often done during the surgery that may be needed to expose the tumor . In such cases, it's customary to take tissue samples not only from the apparent site of the tumor but also from the lymph nodes or other tissues in the neighborhood. This will help measure the tumor's potential or actual spread. This defines the stage of the cancer, so the staging process may be carried out at the same time as the diagnostic process. Of course, the surgeon may also try to carry out the most appropriate therapy at the same time by removing all the visible tumor.
Needle Biopsies For easily accessible tumors and also for some tumors inside the body—in the kidney or pancreas, for example—needle biopsies have become quite common. In this procedure, an anesthetic is placed both in the skin and in the soft tissues under the skin. A very thin needle is then directed into the tumor, and a small bit of tissue is withdrawn for examination. This is called fine needle aspiration (FNA) .
It's very important to be sure the needle is actually in the tumor, so needle biopsies of internal areas are often done in the x-ray department, where an x-ray machine or CT scanner can show the needle's position accurately.
Tumors in the lung and the liver can be diagnosed by a needle biopsy . Even a tumor involving a deep organ like the pancreas can be diagnosed in this way about 80 percent of the time. But the amount of tissue obtained through a needle is not usually enough to diagnose cancers of the lymph glands accurately.
A needle biopsy is not always advisable. When there are vital structures in the area—over the collarbone, for example— there is a risk of complications such as bleeding or nerve damage.
