Tumor removal is a surgical procedure to remove an abnormal growth.
A tumor can be either benign, like a wart, or malignant, in which case it is a cancer. Benign tumors are well
circumscribed and are generally easy to remove completely. In contrast, cancers pose some of the most difficult problems in all of surgery.
Currently 40% of all cancers are treated with surgery alone. In 55%, surgery is combined with other treatments—usually radiation therapy or chemotherapy.
The doctor needs to decide if surgery should be done at all. Because cancers spread (metastasize) to normal tissues, sometimes at the other end of the body, the ability of surgery to cure must be addressed at the outset. As long as the cancer is localized, the initial presumption is that cure should be attempted by removing it as soon as possible.
Non-curative surgery may make other treatments more effective. "Debulking" a cancer—making it smaller—is thought to assist radiation and chemotherapy to get to the remaining pieces of the cancer and be more effective.
Another important function surgery performs in cancer treatment is accurately assessing the nature and extent of the cancer. Most cancers cannot be adequately identified without a piece being placed under a microscope. This piece is obtained by surgery. Surgery is also the only way to determine exactly how far the tumor has spread. There are a few standard methods of comparing one cancer to another for the purposes of comparing treatments and estimating outcomes. These methods are called "staging." The most universal method is the TNM system.
Other methods of staging include Duke's method and similar systems, which add to the above criteria the degree of invasion of the cancer into the surrounding tissues.
Staging is particularly important with such lymphomas as Hodgkin's disease. These cancers may appear in many places in the lymphatic system. Because they are very radiosensitive, radiation treatment is often curative if all the cancer is irradiated. Therefore, it must all be located. Surgery is a common, usually essential, method of performing this staging. If the disease is too widespread, the staging procedure will dictate chemotherapy instead of radiation.
Curative cancer surgery demands special considerations. There is a danger of spreading or seeding the cancer during the process of removing it. Presuming the cancer cells can grow almost anywhere in the body they end up, the surgeon must not "spill" cells into the operating field or "knock them loose" into the blood stream. Special techniques called "block resection" and "no touch" are used. Block resection means taking the entire specimen out as a single piece. "No touch" means that only the normal tissue removed with specimen is handled; the cancer itself is never touched. This prevents "squeezing" cancer cells out into the circulation. Further, in this technique pains are taken to clamp off the blood supply first, preventing cells from leaving by that route later in the surgery.
There are four types of biopsy techniques:
Once surgical removal has been decided, an oncologic surgeon will remove the tumor whole, taking with it a large section of the surrounding normal tissue. The healthy tissue is removed to minimize the risk of possible seeding.
When surgical removal of a tumor is unacceptable as a sole treatment, a portion of the tumor is removed to "debulk" the mass. Debulking aids radiation and chemotherapy treatments.
Retesting and periodical examinations are necessary to ensure that a tumor has not reformed after total removal.
The possibility of mestastasis and seeding are risks that have to be considered in consultation with an oncologist.
Longo, Dan D. "Approach to the Patient with Cancer." In Harrison's Principles of Internal Medicine, ed. Anthony S. Fauci, et al. New York: McGraw-Hill, 1997.
Morton, Donald M. "Oncology." In Principles of Surgery, ed. Seymour I. Schwartz. New York: McGraw Hill Inc., 1989.
J. Ricker Polsdorfer, MD
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Author Info: J. Ricker Polsdorfer MD, The Gale Group Inc., Gale, Detroit, Gale Encyclopedia of Medicine, 2002 |