LUNG CANCER FACTS

Lung cancer is the second most common type of cancer, and results in more deaths than breast, colorectal and prostate cancer combined. However, advances in treatment, especially in the field of radiation therapy, have helped improve the prognosis for lung cancer.

The most common cause of lung cancer is smoking However, there are other risk factors that can increase your chances of developing cancer later in life, including exposure to radon gas, asbestos, and silica; air pollution; family history of lung cancer; and past lung disease that leaves scarring.

The term “lung cancer” actually encompasses several different types of tumors. The staging of the disease depends largely on the size and location of the tumor, as well as whether the cancer has spread.

The most common type of lung cancer is non-small cell cancer, which accounts for about 85 percent of lung cancer cases. Non-small cell cancers include three types of tumors:

• Adenocarcinomas, which form in the mucus-secreting glands of the lungs;
• Squamous cell or epidermoid, which form in the brachial tubes; and
• Large-cell carcinomas, which are non-small cell tumors that do not meet the criteria for either of the other two types.

Stage I non-small cell lung cancer means that the cancer is contained to the lungs only. Stage II means that the cancer has spread to nearby lymph nodes, while stage III means that the cancer has spread to the lymph nodes in the middle of the chest. If the lymph nodes on just one side of the chest are affected, that is stage IIIA, while lymph nodes on both sides of the chest and above the collar bone warrant a Stage IIIB diagnosis. Finally, Stage IV lung cancer is the most advanced stage, in which the cancer has spread to both lungs, the fluid around the lungs, and/or other organs.

The second, less common, type of lung cancer is small-cell lung cancer. This type of tumor grows faster, and spreads sooner than the non-small cell cancer. Because it is more rare, the staging for this type of cancer is considered either “limited” or “extensive.” Limited indicates that the cancer is contained in one lung, and possibly nearby lymph nodes; while extensive means that the cancer has spread to both lungs and potentially throughout the body.

Doctors use surgery, chemotherapy and radiation, or a combination of the three, to treat both types of lung cancer.

• Surgery. Surgery is used most often in early stage lung cancer. Depending on the size and location of the tumor, the surgeon may remove all or part of a lobe, or the entire lung. However, not all patients are good candidates for surgery. Not only must they have good lung function, but surgery is not effective for cancer that has metastasized, or for small-cell cancer.
• Chemotherapy. Small-cell lung cancer tends to respond well to chemotherapy. Chemotherapy also is used in advanced stages of non-small cell lung cancer. However, the side effects of chemo often make the patient feel worse than the disease itself, and can cause additional pain and severe side effects.
• Radiation therapy. Radiation uses powerful radiation beams to shrink tumors and kill cancer cells. Often used in conjunction with surgery or chemotherapy, it’s also a viable option when surgery isn’t appropriate. For example, the stereotactic body radiation therapy (SBRT) offered at the Anchorage-based Alaska CyberKnife Center at Providence Cancer Center relies highly advanced tumor-tracking software and robotics to deliver radiation with pinpoint accuracy. We can treat tumors in as few as one to five visits, a fraction of the time of other treatments — without a lengthy recovery time, invasive procedures or pain.

As with every other type of cancer, early detection of lung cancer increases long-term survival rates. However, because the lungs are so large, and because most of the symptoms of lung cancer mimic those of other conditions, lung cancer is rarely detected in its early stages. Only about 15 percent of lung cancer cases are detected when the disease is at a stage I or stage II. The vast majority of lung cancer cases are discovered in stage III or stage IV, when the disease has spread beyond the lungs and into the nearby lymph nodes and other organs.

However, studies are showing advances in early detection, and a diagnosis of late stage lung cancer does not always equal a poor prognosis. With advanced radiation treatments, such as those offered by the CyberKnife System, the long-term survival rate for lung cancer patients increases. In fact, more than half of all lung cancer patients who are treated in the early stages live five years or longer post-diagnosis and later stage patients can live five years or longer without disease progression.