Understanding the Most Common Lung Cancer in Smokers

Explore how smoking impacts lung cancer risk, the most prevalent lung cancers in smokers, and what factors increase vulnerability.

By Sneha Tete, Integrated MA, Certified Relationship Coach

Created on Sep 25, 2025

Explore how smoking impacts lung cancer risk, the most prevalent lung cancers in smokers, and what factors increase vulnerability.

Lung cancer is the leading cause of cancer deaths worldwide, and smoking remains the dominant risk factor. This article explores the most common types of lung cancer found in smokers, details about their characteristics, additional risk factors including secondhand smoke, and the importance of prevention and screening.

How Smoking Increases the Risk of Lung Cancer

Cigarette smoke contains over 7,000 chemicals, at least 70 of which are known to cause cancer. Inhaling these substances damages lung tissue at the cellular level, dramatically increasing the risk of developing lung cancer. Smoking is responsible for about 80% of all lung cancer deaths, making it by far the most significant controllable risk factor.

Tobacco use causes an estimated 90% of lung cancer cases.
The risk increases with both the duration (years smoked) and intensity (number of cigarettes daily) of smoking.
Even alternative forms of tobacco (like cigars or pipes) and menthol cigarettes heighten the risk considerably.
Exposure to secondhand smoke also contributes to thousands of lung cancer deaths each year.

Types of Lung Cancer: An Overview

Lung cancer is not a single disease but an umbrella term for cancers that originate in the pulmonary tissues. The two primary categories are:

Non-small cell lung cancer (NSCLC): The most prevalent type, accounting for 80–85% of cases.
Small cell lung cancer (SCLC): A more aggressive form, highly linked to smoking, and accounts for 10–15% of cases.

Type of Lung Cancer	Prevalence	Primary Association	Growth/Spread Characteristics
Non-Small Cell Lung Cancer (NSCLC)	80–85% of all lung cancers	More common overall; also frequent in smokers	Usually grows/spreads more slowly than SCLC
Small Cell Lung Cancer (SCLC)	10–15% of all lung cancers	At least 95% of cases linked to smoking	Very aggressive, rapid growth and early spread

The Most Common Lung Cancers in Smokers

While both major types of lung cancer are linked to smoking, small cell lung cancer (SCLC) is most strongly associated.

Small Cell Lung Cancer (SCLC): At least 95% of SCLC cases are found in people with a current or past history of smoking. It is rarely seen in lifelong non-smokers. SCLC is aggressive, often discovered after it has spread, and requires urgent medical treatment.
Non-Small Cell Lung Cancer (NSCLC): While NSCLC is the most common overall, important subtypes within this group also strongly correlate with smoking, especially squamous cell carcinoma.

Key NSCLC Subtypes

Adenocarcinoma: Originates in the glandular (mucus-producing) cells lining the lungs. It is the most common lung cancer in non-smokers but is also frequently found in smokers. Located often in the lung’s periphery, it can also affect those exposed to environmental toxins.
Squamous Cell Carcinoma: Develops in the thin, flat cells lining the airways. Traditionally found more centrally, near major airways (bronchi), this subtype has a strong link to a history of tobacco use.
Large Cell Carcinoma: A less common but still significant NSCLC subtype, capable of arising anywhere in the lungs and known for rapid growth.

Among these, squamous cell carcinoma shows the highest relative association with a history of tobacco abuse, while adenocarcinoma, though statistically most prevalent in non-smokers, remains more common in smokers due to their overall higher risk profile.

Other Risk Factors for Lung Cancer

While smoking is the dominant risk factor, some additional contributors can further increase lung cancer risk:

Secondhand smoke: Non-smokers exposed to tobacco smoke are at increased risk. About 7,000 lung cancer deaths in the U.S. each year are attributed to secondhand smoke exposure.
Radon gas: This naturally occurring radioactive gas, present in some buildings, is the second-leading cause of lung cancer after tobacco smoke.
Occupational exposure: Asbestos, diesel exhaust, arsenic, and other industrial chemicals can increase lung cancer risk, especially in combination with smoking.
Family history: A genetic predisposition or family history of lung cancer can raise your risk.
Previous cancer treatment: Radiation therapy to the chest for other cancers may contribute to later lung cancer risk.

Risk Factors You Cannot Change

Genetics: Some people inherit gene changes from their parents that increase their risk for lung cancer, regardless of smoking.
Age: The risk of lung cancer increases with age, most cases being diagnosed in people aged 65 or older.

Common Symptoms of Lung Cancer

Early lung cancer may not cause noticeable symptoms. As cancer grows or spreads, symptoms often become more obvious:

Persistent cough
Coughing up blood or rust-colored sputum
Shortness of breath
Chest pain, especially when breathing or coughing
Wheezing
Hoarseness
Frequent infections, such as bronchitis or pneumonia
Unexplained weight loss, fatigue, or appetite loss

Diagnosing Lung Cancer in Smokers

If lung cancer is suspected, a series of steps are typically followed to confirm the diagnosis and determine the best course of treatment:

Imaging tests: Chest X-rays, CT scans, or PET scans to locate abnormalities.
Tissue sampling (biopsy): Obtaining tissue for laboratory analysis to confirm the type and aggressiveness of cancer.
Molecular testing: Identifies genetic mutations or markers that might influence treatment options.
Staging: Determines how far cancer has spread, which guides prognosis and therapy choices.

Prevention and Screening

Reducing lung cancer risk, especially for current and former smokers, remains a public health priority:

Don’t start or quit smoking: The single most effective way to lower risk. Former smokers who quit continue to reduce their risk over time, though they remain at higher risk than never-smokers.
Avoid secondhand smoke: Banning indoor smoking, reducing exposure in public spaces, and advocating smoke-free environments are critical measures.
Test for radon: Especially if you live in areas known for elevated levels, test your home and mitigate if necessary.
Use protective measures at work: For those in high-risk industries, proper protective equipment can help limit exposure to carcinogens.
Routine screening: Low-dose CT scans are recommended for people aged 50–80 who have a long history of heavy smoking, even if they quit within the past 15 years.

Treatment Options for Lung Cancer

Treatment will depend on the type, location, and extent of the lung cancer, as well as the patient’s overall health. Options may include:

Surgery: Removing all or part of the lung, typically for early-stage NSCLC.
Radiation therapy: High-energy rays used to target and destroy cancer cells.
Chemotherapy: Drugs that kill rapidly dividing cells, often used in SCLC and more advanced NSCLC.
Targeted therapy: Drugs that block specific molecules involved in cancer growth, useful in some NSCLC cases.
Immunotherapy: Stimulates the patient’s immune system to attack cancer cells.

Early detection is crucial for the best outcomes, as many lung cancers are discovered only after they have advanced to later stages.

Latest Research and Future Outlook

Ongoing research continues to improve the diagnosis, treatment, and prevention of lung cancer. Advances include:

Personalized treatment plans based on specific cancer mutations.
Development of new-targeted and immune-based therapies.
Research into vaccines against certain types of tumor growth.
Improvements in early detection, including screening programs for at-risk populations.

Frequently Asked Questions (FAQs)

What type of lung cancer is most common in smokers?

Both small cell lung cancer (SCLC) and certain types of non-small cell lung cancer (NSCLC), such as squamous cell carcinoma, are common in smokers. SCLC is particularly rare in lifelong non-smokers and almost exclusive to those with a smoking history.

Can secondhand smoke cause lung cancer?

Yes. About 7,000 deaths from lung cancer in the U.S. each year are linked to secondhand smoke. Non-smokers exposed to secondhand smoke have a significantly higher risk of lung cancer compared to those unexposed.

How much does quitting smoking reduce lung cancer risk?

Quitting reduces your risk significantly. While former smokers remain at a higher risk than never-smokers, risk continues to drop with every year smoke-free. Early cessation yields greater benefits.

Are there lung cancers that affect non-smokers?

Yes. Adenocarcinoma is the most common lung cancer found in non-smokers. Radon exposure, air pollution, genetics, or previous chest radiation can also cause lung cancer in non-smokers.

Should ex-smokers be screened for lung cancer?

Yes. Regular screening with low-dose CT scans is recommended for adults aged 50 to 80 who have a history of heavy smoking, including those who have quit within the last 15 years.

Key Takeaways

Smoking is the leading cause of lung cancer, driving most cases of both small cell and non-small cell lung cancer.
SCLC is almost exclusively associated with smoking, while NSCLC subtypes like squamous cell carcinoma are also strongly linked to tobacco use.
Secondhand smoke, radon exposure, occupational hazards, and genetics are additional important risk factors.
Prevention—especially smoking cessation—and regular screening are key to reducing lung cancer’s burden.

If you or someone you know is struggling to quit smoking, resources such as national quitlines and clinical support are available to help start the journey toward lung health.

References

Author

Sneha TeteBeauty & Lifestyle Writer

Sneha is a relationships and lifestyle writer with a strong foundation in applied linguistics and certified training in relationship coaching. She brings over five years of writing experience to thebridalbox, crafting thoughtful, research-driven content that empowers readers to build healthier relationships, boost emotional well-being, and embrace holistic living.

Read full bio of Sneha Tete