Is My Cough a Lung Cancer Cough?

Characteristics & Differences

man coughing with female doctor listening with stethoscope
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Are you worried that your cough could be caused by lung cancer? Since lung cancer is most treatable in the early stages of the disease, finding a cancer as early as possible is extremely important. Unfortunately, there is no way to know conclusively if a cough is due to lung cancer based on symptoms alone. That said, there are some signs and symptoms as well as risk factors that make it more likely that a cough may be a warning sign of lung cancer.

 What should you know if you’ve been coughing?

Types of ​Cough

Chronic vs Acute and Productive vs Non-Productive

At least half of people diagnosed with lung cancer have a chronic cough at the time of diagnosis. A chronic cough is defined as a cough that lasts for at least eight consecutive weeks, and many people say that they had a cough that just wouldn’t go away. A cough may be dry, or you may cough up mucus (called a productive cough.) It can occur at any time of day, and many people say that it interferes with sleep, resulting in daytime tiredness. A cough may be similar to symptoms people have had in the past due to allergies or bronchitis, and therefore may not at first cause someone to be concerned about cancer.

Other Symptoms Associated With a Cough

The occurrence of additional symptoms may increase the likelihood that a cough is serious. Studies have looked at people with lung cancer in order to determine what symptoms were present in the year prior to their diagnosis.

This research found the following symptoms to be independently predictive of lung cancer:

  • Coughing up bloodCoughing up blood (also called hemoptysis) can be a warning sign of lung cancer, and in fact is the only sign present in 7 percent of people at the time of diagnosis. This is often just a small amount of blood, such as a blood tinged tissue, yet any amount should be evaluated carefully by your doctor.
  • Shortness of breathShortness of breath (also called dyspnea) may be very subtle at first. Many people with lung cancer say that they first dismissed this symptom as being due to a sedentary lifestyle or growing older. 
  • Chest pain – Many people mention that they feel lung pain before they are diagnosed with lung cancer. The lungs themselves do not have nerves that sense pain, but pain can be due to the pressure of a tumor on nerves, pain in the ribs from cancer that has spread to the bones, muscle strains (or even rib fractures) from repeated coughing, as well as several other mechanisms. Pain that occurs with a deep breath also called pleuritic chest pain or pleurisy, is also common among people who are later diagnosed with lung cancer.
  • Hoarseness – Some people experience hoarseness before their diagnosis. This could be due to coughing, but could also be due to things such as a tumor pressing on nerves that travel to the vocal cords.
  • Unexplained weight lossUnexplained weight loss or losing weight when you are not trying may be a symptom of lung cancer. Unintentional weight loss is defined as the loss of 5 percent or more of body weight over a six- to 12-month period, roughly 7.5 pounds in a 150-pound person. There are several other serious causes for this finding and you should always see your doctor if your weight is dropping, even if you are feeling happy to see the scale move down.
  • Respiratory infections – Repeated infections such as pneumonia and bronchitis are common before lung cancer is diagnosed. Many people who are diagnosed with lung cancer say that their symptoms were first dismissed, even by doctors, as being due to a cold, bronchitis, or other infections. Others are treated for several episodes of bronchitis or pneumonia before the diagnosis is finally made.
  • Spontaneous smoking cessation – It’s been found that a significant number of people with lung cancer reduce the number of cigarettes they smoke, or spontaneously quit smoking prior to their diagnosis—often with very few symptoms of withdrawal. The reason behind this is unknown, but may be related to trying to ease the symptom of coughing or a subconscious fear of developing lung cancer. We don’t know why this happens, but it could be that some lung cancers produce chemicals that decrease the addictiveness of nicotine. If you've never been able to quit before, and suddenly it seems easy, talk to your doctor.

    Risk Factors

    Some risk factors for lung cancer, for example, smoking and exposure to secondhand smoke, are well known, whereas others are not. Some risk factors include:

    • Smoking currently or in the past – Certainly smoking is a risk factor for developing lung cancer, with 80-90 percent of people diagnosed having a history of smoking at some time. Yet 80 percent of people who are diagnosed with lung cancer today do not smoke; they are either former smokers or never smoked. Unfortunately, unlike heart disease which drops precipitously when a person quits smoking, lung cancer risk never returns to normal.
    • Exposure to RadonExposure to radon in the home is the second leading cause of lung cancer and the leading cause in non-smokers and it's thought that levels are elevated in one in 15 homes in the United States. If your level has never been tested, do this along with making an appointment to see your doctor.
    • Secondhand smoke – It’s thought that secondhand smoke accounts for around 7,000 cases of lung cancer in the United States each year.
    • A family history of lung cancer – A genetic predisposition to lung cancer can run in families. This is especially true when lung cancer is found in nonsmokers, in young people, and in women. Having a mother, father, sibling, or child with a history of lung cancer doubles your risk for developing the disease.
    • Radiation to the chest – Radiation therapy, such as for breast cancer or Hodgkin's disease increases your risk of developing lung cancer.
    • Job exposuresOccupational exposure to chemicals and other substances may increase your lung cancer risk and is considered a factor in up to 27 percent of lung cancers in men.

    Diagnosis of a Cough That Could be Lung Cancer

    Sometimes a chest X-ray will find lung cancer, but it’s important to keep in mind that even if you’ve had a chest x-ray recently that was normal, you could still have lung cancer. In the past chest x-rays were done to screen people for lung cancer, but it was found that x-rays failed to detect lung cancer at an early enough stage to save lives.

    It can't be overstated that chest x-rays can miss lung cancer. If you have symptoms which could be lung cancer, always ask for a chest CT scan. There are a multitude of stories out there of people being reassured that their chest x-ray was normal, only to learn later that they had lung cancer (and due to the delay caused by a normal x-ray, can make the difference between an early stage lung cancer and one which has spread.

    When to Call Your Doctor

    If you have a persistent cough—even if you have never smoked, do not have any other symptoms, or believe there is a good explanation for your cough—make an appointment to see your doctor. If you and your doctor are concerned, a chest CT scan, bronchoscopy, or other tests may be recommended. If your symptoms persist and you don’t have an explanation, consider getting a second opinion. Many people with lung cancer say there was a long delay in their diagnosis, and some say that their doctors didn’t take them seriously. Keep in mind that non-smokers can get lung cancer, and in fact, the majority (yes, over 80 percent) of people who develop lung cancer today are either non-smokers or have quit smoking in the past. In 2017 lung cancer in never smokers is the 6th most common cause of cancer deaths in the United States.

    While we are trying to get the word out to non-smokers that lung cancer can and does occur in people who haven't smoked, but those who smoke need this reminder as well. A 2016 study found that people who smoke are less likely than non-smokers to seek out medical care for the warning signs of lung cancer—such as a cough. If you smoke and cough, don't hesitate to call your doctor.  And remember, nobody deserves lung cancer. Each and every person, whether they have never smoked or have chain smoked their entire life, deserve the absolute best of concern, compassion, and excellent medical care for cancer.

    Risk Calculator

    Memorial Sloan Kettering offers a tool in which certain people may calculate their risk of lung cancer. It is designed for people between the ages of 50 and 75 who smoke or have smoked in the past. With this tool, you are asked to sign a disclaimer indicating that you are aware it is not a substitute for medical care. Keep in mind that this is only a statistical tool, and may easily miss lung cancer in individual people, and may either over-rate or under-rate your risk.​

    Sources:

    Centers for Disease Control and Prevention. Lung Cancer. Updated 01/19/16. http://www.cdc.gov/cancer/lung/index.htm

    Friedemann, S., Whitaker, K., Winstanley, K., and J. Wardle. Smokers are less likely than non-smokers to seek help for a lung cancer 'alarm' symptom. Thorax. 2016 Feb 24. (Epub ahead of print).

    Iven-Omofoman, B. et al. Using socio-demographic and early clinical features in general practice to identify people with lung cancer earlier. Thorax. 2013. 68(5):451-9.

    National Cancer Institute. Non-Small Cell Lung Cancer Treatment (PDQ) – Health Professional Version. Updated 05/11/16. https://www.cancer.gov/types/lung/hp/non-small-cell-lung-treatment-pdq#section/all

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