Non-Small Cell Lung Cancer

Description

Alternative Names

Staging Systems

Tests to Determine Cancer Stage. Once a diagnosis of non-small cell lung cancer has been made, the physician makes treatment choices by determining the cancer's stage (how large the tumor is and how far the cancer has spread). To stage the cancer and determine other aspects of the disease, a number of tests are conducted:

• The cancer cells are examined microscopically for size, shape, and other configurations.
• Computer tomography (CT), magnetic resonance imaging (MRI), or both are used to scan the lung and perhaps other locations, such as the liver, upper abdomen, and brain, are used to determine the extent of the disease.

Physical Examination. A detailed physical examination of the whole body is very important to identify or rule out metastases to other areas and to determine the general condition of the patient. For example, questions about vertigo or headaches can help the doctor determine if the cancer has spread to the brain, while bone or joint pain might suggest the presence of bone metastases. The doctor will also look for head and neck symptoms that might reveal the presence of other tumors. Also, according to a 2000 review, the patient's weight loss and ability to function are two critical factors for predicting survival following treatment. Patients who are mobile and have lost less than 10% of their pre-treatment weight tend to have better survival rates.

Staging Systems

In lung cancer, disease stage at diagnosis is a major factor in determining how to treat the cancer and how long the patient can be expected to live. In general, survival is longest for patients with very early-stage disease and shortest for patients with very advanced disease that has spread to several regions of the body. Staging is based on the results of physical and surgical examinations, laboratory and imaging tests, and biopsies.

• To determine the stage, medical professionals first categorize each tumor by size and by how far it has extended. This identification method is called the TNM system.
• The TNM categories then determine the stage (numbered 0 to IV), which indicates how advanced the cancer is.

Other Factors Determining Treatment Choices and Outcome

In addition, staging factors are also used to help determine treatment and outlook. The following suggest a more aggressive disease:

• The presence of respiratory symptoms.
• A tumor larger than 3 cm.
• High numbers of blood vessels in the tumor.

Researchers are always looking for more accurate ways to determine a treatment and prognosis for lung cancer. For example, some research involves specific biomarkers and related microscopic blood vessel development (angiogenesis) within tumors that might eventually help determine how aggressive a cancer is likely to be and the optimal treatment approach.

General Treatment Approach After Staging

If the cancer is still localized, surgery can produce five-year survival rates of up to 75% in stage I patients and up to 50% in stage II patients. Unfortunately, very few patients are diagnosed at such early stages. In locally advanced stages, the standard treatment is concurrent radiation and chemotherapy. However, even with this approach average survival times are less than two years. Even if an initial tumor has been surgically removed or irradiated, cancer recurrence rates are very high. (The risk for recurrence is lower in smokers who quit after treatment.)

On an encouraging note, advances in therapies for later stage lung cancer are now offering some hope for improving survival. Still at this time, the mortality rate for lung cancer is still extremely high, and reports of improved response or survival rates using drugs or combinations therapies do not mean cures. Ultimately, the patient must weigh a diminished quality of life using some aggressive treatments against a chance for a modestly prolonged life.