Symptoms and Stages of Lung Cancer
It usually starts as a cough or shortness of breath. Chest pains follow. More signs and symptoms come. Each year, lung cancer kills 1.3 million people—the same as the population of Hawaii—making it the most common cause of cancer-related death (Lung Cancer Research Foundation, 2012). There are two main categories—non-small-cell and small-cell carcinoma—and several types of lung cancer, each having its own characteristics.
From early warning signs to stage IV bronchioloalveolar carcinoma, the following article features the causes, symptoms, types, and stages of lung cancer.
Causes and Risk Factors
The easiest way to get lung cancer is to smoke tobacco. Even secondhand smoke increases your risk. Along with a family history, other risks to increase chances of developing lung cancer include:
- high levels of air pollution
- arsenic in drinking water
- radon gas
- exposure to cancer-causing chemicals like uranium, coal products, gasoline and diesel exhaust
With smokers, a cough is usually dismissed as just a cough. If it doesn't go away or blood comes with it, it's usually a sign of something serious. Wheezing, shortness of breath, and chest pains are other ignored symptoms of lung cancer.
Other signs include loss of appetite, weight loss, weakness, fatigue, difficulty in swallowing, hoarse voice, joint pain, facial paralysis, drooping eyelids, or bone pain. Some of the signs are associated with less serious conditions, so it's important to see your doctor if you are experiencing some of them.
Non-Small-Cell Lung Carcinoma
Non-small-cell lung carcinoma, the most common form of lung cancer, is broken up into three categories:
- Squamous: This type usually starts near the central bronchus, where a hollow cavity and necrosis (death of cells) form in the center of the tumor.
- Adenocarcinoma: This is the most common form of lung cancer in nonsmokers. It affects peripheral lung tissue. A subtype, bronchioloalveolar carcinoma, is the type most commonly found in women who never smoke.
- Large-Cell Lung Carcinoma: This type grows and spreads quickly in any part of the lung, making treatment difficult.
Small-Cell Lung Carcinoma
Small-cell lung carcinoma forms in the larger airways and is strongly linked with smoking. While less common, it carries a worse prognosis because it has usually metastasized (spread to other organs) by the time it is detected. Metastasis is explained below.
Metastatic cancer begins in one part of the body and spreads to other areas. Part of the reason why lung cancer is so deadly and hard to treat is that metastasis starts early on after the cancer has formed. Common sites for lung cancer metastasis include the adrenal glands, liver, brain, and bone. The lungs are a common place where other metastatic cancers can land.
Stages of Cancer
Lung cancer uses the TNM classification scale, which denotes several characteristics. Larger numbers mean the tumor is more advanced (National Cancer Institute, 2012).
The more common staging scale uses Roman numerals:
- Stage 0: Cancer is only present in the cells where it formed.
- Stage I: Cancer has grown but has not metastasized.
- Stage II, III: While still local to its origin, the cancer is spreading and possibly affecting other organs nearby.
- Stage IV: Cancer has fully metastasized and spread to other organs throughout the body.
Lung cancer can be deadly but you can help prevent it. The easiest way to cut down your risk is to quit smoking and instantly start feeling the benefits. Within minutes, your body will start to recover.
Along with a good diet, exercise, and other healthy choices, staying informed about the risks of lung and other cancers is key to prevention.
Lung cancer is a very common type of cancer. In fact, lung cancer is the second leading type of cancer diagnosed in American men and women. Lung cancer is also the leading cause of cancer-related deaths for both American men and women. One in every four cancer-related deaths is from lung cancer.
Cigarette smoking is the leading cause of lung cancer. Men who smoke are 23 times more likely to develop lung cancer. Women who smoke are 13 times more likely when compared with nonsmokers.
About 14 percent of new cancer cases in the United States are lung cancer cases. That equals out to about 225,000 new cases of lung cancer each year.
Types of lung cancer
There are three main types of lung cancer. One type, non-small cell lung cancer, is the most common. The type you have affects the type of treatment you’ll receive.
Non-small cell lung cancer (NSCLC)
This is the most common type of lung cancer. Roughly 85 percent of people diagnosed with lung cancer each year have non-small cell lung cancer.
Doctors further divide NSCLC into stages. Stages refer to the location and scale of the cancer, and affect the way your cancer is treated.
Small cell lung cancer (SCLC)
Less common than NSCLC, SCLC is only diagnosed in 10 to 15 percent of people diagnosed with lung cancer. This type of lung cancer is more aggressive than NSCLC and can spread quickly. SCLC is also sometimes called oat cell cancer.
Doctors assign stages to SCLC using two different methods. The first is the TNM staging system. TNM stands for tumor, lymph
nodes, and metastasis. Your doctor will assign a number to each category to help determine the stage of your SCLC.
More commonly, small cell lung cancer is also divided into limited or extensive stage. Limited stage is when the cancer is confined to one lung and may have spread to nearby lymph nodes. But has not traveled to the opposite lung or distant organs.
Extensive stage is when cancer is found in both lungs and may be found in lymph nodes on either side of the body. It may have also spread to distant organs including bone marrow.
Because the system for staging lung cancer is complex, you should ask your doctor to explain your stage and what it means for you. Early detection is the best way to improve your outlook.
Lung carcinoid tumor
This is the least common of the three main types of lung cancer. Less than 5 percent of lung cancers diagnosed each year are lung carcinoid tumors. These slow growing tumors rarely spread. Lung carcinoid tumors are also sometimes called neuroendocrine tumors.
Doctors stage lung carcinoid tumors using the TNM system, the same as the one used for NSCLC.
Lung cancer and gender
Men are slightly more likely to be diagnosed with lung cancer than women. Almost 118,000 men are diagnosed in the United States every year. For women, the number is close to 106,000 a year.
This trend holds up for lung cancer-related deaths, too. About 158,000 people in the United States will die because of lung cancer each year. Of that number, 86,000 are men, and 72,000 are women.
To put that into perspective, the chance a man will develop lung cancer in his lifetime is 1 in 14. For women, that chance is 1 in 17.
Lung cancer and age
More people die from lung cancer every year than from breast, colon, and prostate cancers combined. The average age of a lung cancer diagnosis is 70. The majority of diagnoses are in adults over the age of 65. Less than two percent of lung cancer diagnoses are made in adults under age 45.
Lung cancer and race
Black men are 20 percent more likely to develop lung cancer than white men. The rate of diagnosis among black women is about 10 percent lower than in white women. The total of men diagnosed with lung cancer is still higher than the number of black women and white women diagnosed with the disease.
Lung cancer is a very serious type of cancer. It is often fatal for people who are diagnosed with it. But that is slowly changing.
People who are diagnosed with early stage lung cancer are surviving in growing numbers. More than 430,000 people who were diagnosed with lung cancer at some point are still alive today.
Each type and stage of lung cancer has a different survival rate. A survival rate is a measure of how many people are alive by a certain time after they were diagnosed. For example, a five-year lung cancer survival rate tells you how many people are living five years after they were diagnosed with lung cancer.
Remember that survival rates are only estimates, and everyone’s body reacts to lung cancer, and responds to treatment, in a different way. If you have been diagnosed with lung cancer, many factors will affect your outlook, including your stage, treatment plan, and overall health.
Non-small cell lung cancer (NSCLC)
The five-year survival rate for NSCLC differs depending on the stage of the disease.*All data courtesy of American Cancer Society
Small cell lung cancer (SCLC)
As with NSCLC, the five-year survival rate for people with SCLC varies depending on the stage of the SCLC.*All data courtesy of American Cancer Society
Lung carcinoid tumors
Lung carcinoid tumors are also divided into stages with corresponding survival rates.*All data courtesy of American Cancer Society
If you complete treatments and are declared cancer-free, your doctor will likely want you to maintain regular check-ups. That is because cancer, even when initially treated successfully, can come back. For that reason, after treatment is completed you will continue to follow up with your oncologist for a surveillance period.
A surveillance period will typically last for 5 years because the risk of recurrence is highest in the first 5 years after treatment. Your risk of recurrence will depend on the type of lung cancer you have and the stage at diagnosis.
Once you complete your treatments, expect to see your doctor at least every six months for the first 2 to 3 years. If, after that period of time, your doctor has not seen any changes or areas of concern, they may recommend reducing your visits to once a year. Your risk of recurrence decreases the further out you get from your treatment.
During your follow-up visits, your doctor may request imaging tests to check for the cancer’s return or new cancer development. It is important that you follow up with your oncologist and report any new symptoms right away.
If you have advanced lung cancer, your doctor will talk to you about ways to manage your symptoms. These symptoms can include:
- headaches or other neurological symptoms
- side effects of any treatments