Lung cancer is a leading cause of death, both in the U.S. and worldwide. It’s also largely preventable. Approximately 85 percent of lung cancer cases occur in people who smoke or used to smoke. Fortunately, as the number of smokers declines, the rates of lung cancer are also going down.
Types of Lung Cancer
There are two main types of lung cancer: non-small cell lung cancer and small cell lung cancer. SCLC is very aggressive, and it starts and spreads quickly. Fortunately, only about 15 percent of lung cancers fall into this category.
Non-small cell lung cancers are further classified (and named) based on the type of cells in the tumor, explains Dr. Abraham Chachoua, associate director of cancer services at Perlmutter Cancer Center at NYU Langone Medical Center. “The cells look very different under the microscope,” he says. Even though NSCLCs grow slowly, by the time most people learn they have lung cancer, it’s usually at an advanced stage.
[See: 7 Innovations in Cancer Therapy.]
What Is Staging?
After your oncologist initially diagnoses you with lung cancer, he or she will need to learn a bit more about the specifics of your cancer. This is called staging. Staging helps your doctor decide which treatment options will likely produce the best results. Many of the tests used to diagnose lung cancer — such as a CT scan, biopsy (looking at a sample of tissue) or bronchoscopy (looking directly into the lungs with a scope) — are the same tools used to stage cancer.
Oncologists use the American Joint Committee on Cancer TNM classification system to describe non-small cell lung cancer. T describes the tumor by its size. N specifies whether the tumor has spread to the lymph nodes (part of the immune system). Once a tumor spreads to the lymph nodes, it can travel through the lymph system to another part of your body where it can begin to grow again. M stands for metastasis, which means the tumor has spread to another part of the body.
[See: 7 Things You Didn’t Know About Lung Cancer.]
Stages of Lung Cancer
Staging cancer is complex, explains Dr. Raja Flores, chairman for the department of thoracic surgery and Steven and Ann Ames Professor in Thoracic Surgery at Mount Sinai Medical Center. There are four stages of NSCLC: I, II, III and IV. Each of these stages are further divided into subcategories (such as stage IIA or IIIb) to provide more details about the cancer.
Flores says Stage I lung cancer is limited to part of the lung and has not spread to the lymph nodes. With Stage II, cancer cells are in part of the lung and in lymph nodes close to the tumor. In Stage III, you find cancer cells in lymph nodes further away from the main tumor, near the trachea. And finally, by Stage IV, the tumor has spread outside the chest. “Stage one is the most curable,” Flores says, “and screening is the best way to catch it.” Stage 0, or carcinoma in situ, describes the presence of abnormal cells in the lining of the airways. These cells may eventually develop into cancer.
Oncologists use a two-tiered system to stage small cell lung cancer. They classify SCLC tumors as limited-stage (still localized) or extensive-stage (the cancer has spread).
Patients’ prognosis depends upon their age, general health and how advanced the cancer is at the time of diagnosis. Flores says patients with stage I cancer have a roughly 80 percent chance of being cured with treatment. Because the tumor is still small, it’s less likely to have spread. It also means the oncology surgeon can remove it with a small incision. Advanced lung cancers require major chest surgery. Stage IV lung cancer is not curable. Oncologists offer stage IV patients treatment that alleviates symptoms and prolongs survival (this is called palliative care).
Symptoms of Lung Cancer
Early detection of lung cancer leads to better outcomes. However, people with lung cancer often do not have noticeable symptoms, especially early on. Coughing, shortness of breath, wheezing and coughing up blood can all be a sign of lung cancer. Of course, if you smoke, you’re probably used to coughing and will likely ignore a persistent cough, Chachoua says.
Sometimes people with lung cancer have noticeable symptoms elsewhere in their body. “Cancer can cause symptoms without physically being there,” Chachoua says. It may be because the cancer has spread and is producing symptoms at the new location. Or, the presence of cancer in the body causes the immune system to react to substances produced by the tumor. The medical term for this uncommon phenomenon is paraneoplastic syndromes. Chachoua says paraneoplastic syndromes in lung cancer patients can cause loss of energy, unexplained weight loss or even a rare joint problem (hypertrophic pulmonary osteoarthropathy). These seemingly unrelated symptoms can indirectly lead back to a lung cancer diagnosis.
[See: What Not to Say to Someone With Lung Cancer.]
Bottom line: if you have a long-lasting cough or other, unexplained symptoms, it’s always best to see your doctor and have it checked out.
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What Are the Stages of Lung Cancer? originally appeared on usnews.com
