Lung cancer usually doesn’t cause symptoms in its initial stages, but some people do experience symptoms early on. In this article, we talk about having asymptomatic (no symptoms) lung cancer, when symptoms might show up, and what those symptoms feel like. We’ll also talk about how lung cancer is diagnosed — sometimes by chance — and who should get lung cancer screenings.

You Can Have Lung Cancer Without Symptoms

People can have lung cancer without having any symptoms. One study of approximately 600 people with lung cancer found that 54 percent were asymptomatic and were diagnosed by chance from an X-ray or CT scan that was ordered for other reasons, mainly a routine checkup or as part of an evaluation of conditions or symptoms that weren’t related to the chest.

Having lung cancer without symptoms may mean the cancer is in the early stages, as lung cancer symptoms usually only show when the cancer is more advanced.

For instance, one study showed that people with lung cancer who didn’t have symptoms and were diagnosed by chance more often had earlier-stage lung cancer, and people with symptoms were more likely to have advanced-stage lung cancer. The group that didn’t have symptoms at the time of diagnosis had a better prognosis (outlook) with a three-year overall survival rate of 64 percent, versus 30 percent among the group that had symptoms at the time of diagnosis.

Lung Cancer Symptoms Usually Show up in Later Stages

Cancer stages are sometimes noted with Roman numerals, as stages I through IV (1 through 4). Stage 1 and stage 2 cancer usually don’t cause noticeable symptoms. In these cases, lung cancer is usually diagnosed by chance during routine care.

Although some people do have symptoms in the early stages, for most people with lung cancer, symptoms don’t show up until more advanced stages, once the cancer has spread (metastasized) or grown. For instance, symptoms are more likely to be noticed in stage 3, when cancer has spread to nearby lymph nodes, or if there’s more than one tumor in the same lung.

A lack of symptoms in the early stages is believed to be one of the reasons why lung cancer is often only diagnosed in more advanced stages.

Discuss Possible Lung Cancer Symptoms Right Away

Because lung cancer symptoms might not show up until the later stages, it’s important to talk to your doctor as soon as you notice symptoms. Symptoms of lung cancer include:

• A cough that doesn’t go away or gets worse as time goes on
• Wheezing or shortness of breath
• Chest pain
• Coughing up blood
• Unexplained weight loss
• Constant tiredness

One study found that the following symptoms were more common in people with early-stage lung cancer versus late-stage lung cancer:

• Cough
• Shortness of breath
• Wheezing or chest crackles

A persistent cough or pneumonia that keeps coming back may be one of the early symptoms of lung cancer. However, these symptoms might also be signs of other, less serious health conditions. Lung cancer symptoms being confused for common respiratory illnesses, like bronchitis or pneumonia, can lead to a delayed diagnosis.

One study found that the time between the first recorded symptoms of lung cancer and diagnosis was 570 days (about a year and a half), on average. Other studies have shown shorter time frames between the start of symptoms and diagnosis, but they are still longer than target ranges. The study researchers highlighted the need for interventions to shorten the time between someone showing symptoms and getting diagnostic tests or seeing a specialist.

You know your body best, and if something doesn’t feel right, it’s important to advocate for yourself and be persistent. Lung cancer treatment is most likely to be effective in the early stages.

Lung Cancer Diagnosis Requires Multiple Steps

If you have signs and symptoms of lung cancer, your doctor will first gather the following information:

• Smoking history, if applicable
• Family history
• Personal medical history
• History of exposure to certain chemicals and substances

The next step is imaging, usually a chest X-ray, to see if there are any concerning areas that show up. If there are, your doctor will likely order a CT scan or positron emission tomography (PET) scan to look at those areas in more detail. If the imaging shows something that looks like cancer, a tissue or fluid sample will be taken from the lungs for further examination. The tissue sample is called a biopsy. In addition, another PET or CT scan may be ordered to see if the cancer has spread to other parts of the body.

High-Risk Individuals Need Lung Cancer Screenings

Because lung cancer doesn’t always cause symptoms in the early stages, lung cancer screenings are key for early detection. Lung cancer screening is recommended for people at higher risk of lung cancer, mainly due to a history of smoking. Currently, screening is done with a low-dose CT scan.

The American Cancer Society recommends yearly screening with a low-dose CT scan for people who:

• Are 50 to 80 years old
• Smoke or have smoked in the past
• Have a history of smoking of at least 20 pack-years

One pack-year means smoking one pack of cigarettes per day for one year. To calculate pack-years, the number of packs smoked per day is multiplied by the number of years the person has smoked.

Although screening can allow for early detection of lung cancer, it doesn’t always mean lung cancer will be found early, and it may not find all types of lung cancer.

Talk to your doctor if you have questions about your risk of lung cancer, such as after quitting smoking and if and when it’s time to start screenings. Be sure to ask about the benefits, limits, and potential risks of lung cancer screening to help you know what to expect from getting screened and what the information means for you.

Getting screened won’t prevent you from getting cancer, but it may mean the cancer is found earlier and that you get the treatment you need sooner.

Talk With Others Who Understand

MyLungCancerTeam is the social network for people with lung cancer and their loved ones. On MyLungCancerTeam, more than 13,000 members come together to ask questions, give advice, and share their stories with others who understand life with lung cancer.

Are you at higher risk of lung cancer and getting screened? Have you been diagnosed without having any symptoms? Share your experience in the comments below, or start a conversation by posting on your Activities page.