To have the best chance at beating cancer, early detection is key. Screening tests are important for detecting early signs of cancer in people who may not have symptoms yet. A mammogram is a type of imaging test that can be used to detect breast cancer. Regular mammogram screenings can detect breast tumors when they’re still small, helping to reduce cancer-related deaths.

Mammograms are widely used to diagnose breast cancer, but can they help diagnose lung cancer as well? This article covers how mammograms are used and whether they can detect lung cancer earlier. Early detection of lung cancer helps health care providers start treatment sooner and can lead to better outcomes.

What Is a Mammogram?

The most widely used test in breast cancer screening is a mammogram. This type of imaging test uses low-dose X-rays to examine breast tissue. A radiologist (imaging specialist) studies multiple X-ray images of the breast and looks for abnormalities that could be a sign of a breast tumor. Even if a tumor is too small to be felt or cause problems, a mammogram can find it.

People who don’t have any signs or symptoms of breast cancer may undergo mammograms as a precaution — this is known as screening mammography. On the other hand, a diagnostic mammogram may be given to those with symptoms to confirm a cancer diagnosis.

Although mammograms are useful for detecting breast cancer, they don’t always work perfectly. Sometimes, a screening test may detect a tumor when, in fact, there’s no cancer. This is called a false-positive result and may lead some people to undergo further testing for cancer that they don’t need. This testing can be uncomfortable, expensive, and take up a lot of time. Mammograms may also give false-negative results, meaning the test fails to detect cancer in someone who has breast cancer. This can cause a delay in treatment.

Who Should Get a Mammogram?

To detect breast cancer early, people should get mammograms before they have any signs or symptoms of the disease. Most women should expect to get a mammogram at some point, but some may get screened earlier than others. The American Cancer Society (ACS) has guidelines for when to start breast cancer screening based on a person’s risk of having the disease.

Some people are at a higher risk of having breast cancer based on their family history or genetic testing. These women are more likely to develop breast cancer earlier in life and, therefore, should start getting screened at 30 years old, according to the ACS guidelines. For people without a known breast cancer risk, the guidelines don’t recommend screening mammograms until age 40.

Lung Cancer Screening

To improve the chances of early detection, people can also be screened for lung cancer. The primary test used for lung cancer screening is known as a low-dose computed tomography (LDCT) scan. Similar to mammography, LDCT uses low-dose X-rays to take several images of the lungs. A low-dose CT scan is useful for detecting signs of early-stage lung cancer, although false-positives are possible.

In addition to an LDCT scan, a newer technique called a breath test may be used for lung cancer screening. People with lung cancer often release certain substances in their breath. A lung cancer breath test uses an electronic device that can detect these substances and help diagnose the disease early. Breath tests are not as widely used in screening as LDCT, but they may be faster to do and might have fewer risks.

Lung cancer screening is recommended for people at high risk of having lung cancer. Screening guidelines for lung cancer have been developed by the U.S. Preventive Services Task Force and the ACS. These guidelines recommend lung cancer screening for people who are between 50 and 80 years old and smoke or used to smoke and also have at least a 20-pack-year history of smoking. A pack-year is a measure of smoking that equals smoking one pack of cigarettes a day for one year. Multiply the packs someone smokes a day by the years they smoked to get the pack-year amount. Someone can have a 20-pack-year smoking history if they smoked two packs a day for 10 years or one pack a day for 20 years.

The Importance of Early Screening

Routine screening mammography can help lead to better detection of early-stage breast cancer. When doctors diagnose and treat the disease early, people with breast cancer can live longer.

Similarly, regular screenings for lung cancer can help doctors find the cancer early. Without screening, most cases of lung cancer are diagnosed after the disease is already advanced. By improving the diagnosis of early-stage disease, lung cancer screenings can help improve survival for people with lung cancer.

Although lung cancer screening can be beneficial, it’s not as regularly performed compared to mammograms. Of the people who are eligible for lung cancer screening, fewer than 5 percent get screened. In contrast, an article in the Journal of Medical Screening found that about 70 percent of women have regular mammograms once they’re eligible. The low rate of lung cancer screening is due, in part, to a lack of access to medical centers that can perform the required tests. Improving accessibility to health care is important to reduce the number of deaths from lung cancer.

Can Mammograms Detect Lung Cancer?

Mammograms are crucial for detecting breast cancer early on, but can they also help diagnose lung cancer? Currently, there’s no evidence that mammograms can diagnose lung cancer directly. However, lung tumors can be detected by breast MRI, an imaging test that some people may get as a follow-up to a mammogram.

A study published in 2015 reported that a breast MRI after a mammogram can detect the edges of a lung tumor in people with lung cancer. Another study from 2013 found that a breast MRI can identify breast cancers that have spread to the lungs. In all cases, the lung tumors were ultimately confirmed by a CT scan. Therefore, although mammograms focus on breast tissue, they may prompt follow-up tests that can diagnose lung cancer.

Using Mammograms for Early Lung Cancer Detection

Although mammograms are unlikely to detect lung cancer directly, research studies from the Journal of the American Board of Family Medicine have suggested that mammograms can help women who are at risk of having lung cancer get screened earlier. Most women who undergo mammograms aren’t in a lung cancer screening program, even if they meet the eligibility criteria for lung cancer screening. However, because they already have access to a screening facility for mammograms, they may be able to get regular lung cancer screens as well.

A 2021 study from the Journal of Medical Screening looked at whether routine mammograms could be used to screen more people for lung cancer. Among women who had gotten recent mammograms, the researchers identified those eligible for lung cancer screening and enrolled them in a screening program. They found that the screening helped to diagnose many of these women with early-stage lung cancer. Other women were not in the screening program but eventually were diagnosed with lung cancer. More of these women were diagnosed with late-stage disease and ultimately died of lung cancer.

Getting screened regularly for breast cancer might make it easier to schedule lung cancer screening tests in people who are at a higher risk of getting lung cancer. Therefore, it’s recommended for women who get routine mammograms and who are also at risk for lung cancer to link their mammogram appointments with lung cancer screening. This may lead to an earlier lung cancer diagnosis and a better outcome.

Diagnostic Tests for Lung Cancer

If the screening results by LDCT or breath test show you may have lung cancer, you’ll need additional follow-up tests to confirm a cancer diagnosis. Many different imaging tests can help diagnose lung cancer, including:

• CT scan
• MRI
• Chest X-ray
• Positron emission tomography (PET) scan, either alone or together with CT scan

To confirm a lung cancer diagnosis, your doctor will also take a biopsy (tissue sample) from your lungs and look for cancer cells under a microscope. A biopsy can also help your doctor understand what type of lung cancer you have.

If you haven’t been diagnosed but are concerned about your risk for lung cancer, your doctor can help you better understand screening and diagnostic tests. Additionally, if you already get routine mammograms, ask your doctor about lung cancer screening, too. By being proactive and getting screened early, you may have a better outlook and a longer life.

Talk With Others Who Understand

MyLungCancerTeam is the social support 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.

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