Lung cancer is one of the most common types of cancer diagnosed worldwide. There are two types of lung cancer: small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC). NSCLC accounts for 80 percent to 85 percent of lung cancer diagnoses and includes several subtypes, each of which can affect treatment options and prognosis (disease outlook).

A cancer prognosis is often described using the five-year survival rate, which represents the percentage of people still alive five years after their diagnosis. The five-year survival rate for NSCLC is about 28 percent for all stages combined, the highest five-year survival rate of both types of lung cancer. Early diagnosis and treatment of NSCLC can help improve this outcome.

Factors That Can Affect a Non-Small Cell Lung Cancer Prognosis

In addition to early detection, several factors can influence the disease outlook for NSCLC. These prognostic factors are discussed below.

Age

NSCLC is most commonly diagnosed in older adults. The average age of diagnosis is 70. Younger people (under 40) tend to have a poorer prognosis, although early intervention may improve outcomes.

Overall Health

Overall health plays a significant role in NSCLC prognosis. People who maintain good nutrition, exercise, and have fewer health conditions tend to live longer and have a higher likelihood of achieving remission (reduction or disappearance of cancer signs and symptoms). High levels of inflammation throughout the body can indicate poor health. Recent research suggests that cancers can produce localized inflammation that helps keep them from being attacked by the immune system.

One oncology study showed that people with high levels of inflammation at diagnosis had a worse prognosis than those who had normal levels of inflammation. People with high levels of inflammation often have other complications, such as malnutrition or chronic diseases that negatively affect prognosis.

Unintentional or unexplained weight loss is another poor prognostic factor.

Lifestyle

Smoking is the leading risk factor for NSCLC. The American Cancer Society reports that about 80 percent of lung cancer deaths are related to smoking cigarettes. According to the American Lung Association, men who smoke are 23 times more likely to be diagnosed with lung cancer compared to people who do not smoke. Women who smoke are 13 percent more likely to be diagnosed with lung cancer than people who don’t smoke. The U.S. Preventive Services Task Force recommends annual low-dose CT scans for individuals aged 50 to 80 who currently smoke or have quit within the past 15 years.

Secondhand exposure to smoke also increases the risk of developing and dying from lung cancer. Each year, more than 7,000 U.S. adults who have never smoked die from lung cancer caused by secondhand smoke. People who don’t smoke have a 20 percent to 30 percent higher risk of being diagnosed with lung cancer if they regularly inhale secondhand smoke, such as at work or at home.

The good news is that some lifestyle changes can improve prognosis even after an NSCLC diagnosis. For example, quitting smoking can enhance overall health, improve well-being, and increase the ability to tolerate treatments like chemotherapy.

Immune and Genetic Markers of Cancer

The immune system is designed to recognize and defend against cancer. The types and numbers of immune cells that respond to a tumor can influence NSCLC prognosis. For example, lung tumors that have been invaded by T cells (which can kill cancer cells) tend to have a better prognosis.

Cancer cells can alter their markers to hide from the immune system, leading to a worse prognosis. Tumors that are recognized by the immune system generally have better outcomes. Some therapies focus on activating immune cells to detect and destroy cancer cells.

The over- or underexpression of certain genes and proteins has been linked to NSCLC prognosis. These markers of probable disease outcome are known as prognostic biomarkers. In some cases, the expression of certain proteins can predict how well the cancer cells will respond to treatment. These proteins, known as predictive biomarkers, help doctors design the most effective treatment for each individual living with NSCLC.

Family History

People with family members who’ve been diagnosed with lung cancers may have a higher risk of developing NSCLC. A family history of lung cancers is linked with a decrease in the average age of diagnosis and an increase in the risk of advanced non-small cell lung cancer at diagnosis. This tends to affect women more than men, according to a study in the journal Thoracic Cancer.

Comorbidities

Comorbidities are conditions that can occur alongside a primary condition. Having one or more additional health conditions may affect NSCLC prognosis in several ways. First, some conditions associated with lung cancer, such as chronic obstructive pulmonary disease (COPD) or heart disease, may decrease survival rates independently of NSCLC. Second, comorbidities may also conceal signs and symptoms, leading to delayed diagnosis. Finally, it may be unsafe for a person to undergo certain types of surgery to treat NSCLC if they have certain comorbidities.

Common NSCLC comorbidities include:

• Pulmonary (lung) disease
• Diabetes
• Dementia
• Kidney disease
• Anemia (lack of healthy red blood cells)
• Thrombocytosis (a high platelet count)
• Congestive heart failure

For example, about 34 percent of people living with lung cancer also had anemia, one study found. Older people and people who smoke cigarettes are more likely to have additional conditions that complicate treatment or negatively affect prognosis.

Cancer Stage at the Time of Diagnosis

Other factors can influence a person’s NSCLC prognosis, including the stage of disease at the time of diagnosis and NSCLC subtype. The earlier a cancer is detected, the better the prognosis. However, some signs and symptoms of NSCLC tend to appear only after the disease has spread. This means that most instances of NSCLC are diagnosed at a later stage.

Clinical staging helps doctors determine whether and how far the cancer has spread before treatment begins. This process involves gathering information from physical exams, CT scans, other imaging tests, blood work, and biopsies. The staging results guide the development of a treatment plan and help estimate prognosis.

Overall, tumors that can be surgically removed (also known as surgical resection) are linked to the best prognosis. If surgery is part of treatment, pathological staging may be used to get a more accurate picture of the stage and prognosis. NSCLC staging is based on the TNM system, which assesses the size of the primary tumor (T), the involvement of nearby lymph nodes (N), and whether the cancer has metastasized (M) — spread to other parts of the body.

People living with NSCLC that’s localized (fully contained in the lungs) have a better prognosis than those with metastatic disease. For people living with localized NSCLC, the five-year survival rate is 65 percent. When NSCLC has spread to nearby areas (regional), the five-year survival rate is 37 percent. After cancer has metastasized (distant), the five-year survival rate is 9 percent.

Subtypes of Non-Small Cell Lung Cancer and Prognosis

“NSCLC” is an umbrella term that covers several subtypes of lung cancer. The most common subtypes are the following:

• Large cell carcinoma
• Squamous cell carcinoma
• Adenocarcinoma

These NSCLC subtypes arise from different types of lung cells. Although their treatment and outlook are typically similar, these subtypes may respond differently to treatment. Advanced medicine allows doctors to target specific cancer cell pathways with modern treatment options. This targeted treatment is called personalized medicine and has improved the overall prognosis of NSCLC.

Prognosis After Non-Small Cell Lung Cancer Relapse

Every year, tens of thousands of people in the United States living with NSCLC achieve complete remission, meaning all signs of the cancer disappear. After treatment, most people continue regular visits with their oncologists and get tests including physical exams, CT scans, and blood tests to monitor for signs of cancer relapse. In the first few years after remission, these visits occur every three to six months. After two to three cancer-free years, follow-ups may be reduced to every six months. Prognosis tends to be worse for relapsed disease because returning cancer is often more resistant to treatment.

Prognosis Continues To Improve

The best treatment for NSCLC is prevention. People who never smoked or have quit are at a lower risk of developing lung cancer. Declining smoking rates and advances in NSCLC diagnosis and treatment have led to improved overall survival over the past 30 years. Today, even people with advanced or metastatic lung cancer can often enjoy a higher quality of life, thanks to newer, targeted therapies that help prolong life and improve well-being.

Talk With Others Who Understand

On MyLungCancerTeam, the social network for people with lung cancer and their loved ones, 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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