A Guide to Small-Cell Carcinoma of the Lung

Medically Reviewed By Adithya Cattamanchi, M.D.
Was this helpful?

Small cell lung carcinoma (SCLC) is cancer that starts in the tissues of the lungs. One of the biggest risk factors for SCLC is smoking, but it can also affect people who do not smoke. According to the American Cancer Society, cancer is a disease of many different types. Each type starts in the same way — a cell or a group of cells changes and grows out of control. As those cells grow, they form tumors.

This article will explain more about SCLC, including its stages, symptoms, and causes. It also details risk factors, diagnostic steps, treatment options, and outlook.

What is SCLC?

a man is coughing and sat on a sofa
Alphotographic/Getty Images

SCLC, or oat cell cancer, is named for the size of the cells when viewed under a microscope. It is also the most aggressive form of lung cancer. 

There are two types of lung cancers: SCLC and non-small cell carcinoma (NSCLC).

NSCL is the most common form, with as many as 80–85% of people with lung cancer having this condition. However, SCLC tends to grow and spread more quickly than NSCLC.

Find out more about cancer types here.

What are the stages of SCLC?

While oncologists prefer to use the TNM stages, where T stands for tumor thickness, N for lymph node involvement, and M for metastasis (spread), most people are acquainted with number staging.

There are five basic stages of SCLC:

  • Stage 0: Cancer is present but confined to a small area.
  • Stages 1-3: The number indicates the size of the tumor and how much it has spread to nearby tissues.
  • Stage 4: Cancer has spread to other tissues.

Learn more about the stages of SCLC.

Staging for SCLC

SCLC has two stages: limited and extensive. These indicate the seriousness of the cancer and how to treat it.

The limited stage tells doctors that the cancer is on one side of the chest and typically requires treatment with chemotherapy and radiation therapy at the same time.

Extensive stage SCLC means cancer has spread outside the lung to other areas of the body. People with extensive SCLC typically require chemotherapy to manage the disease. 

Learn more about the extensive stage of SCLC.

What are the symptoms of SCLC?

No two people exhibit symptoms of SCLC in the same way. Some people might not have symptoms until the later stages of the disease.

A few common symptoms are: 

If you develop any concerning symptoms, contact your healthcare professional to discuss them as soon as possible.

Read our guide to lung cancer symptoms here.

What causes SCLC?

There are several causes of SCLC. The primary cause is smoking.

According to the Centers for Disease Control and Prevention (CDC), people who smoke are 15 to 30 times more likely to develop lung cancer than people who do not smoke.

Exposure to certain chemicals, such as radon, asbestos, diesel exhaust, and silica, can also cause lung cancer.   

Learn tips about quitting smoking.

What are the risk factors of SCLC?

Smoking is the main cause of SCLC. Secondhand smoke also increases your risk of SCLC.

The following factors can also raise your risk of developing lung cancer: 

  • radiation treatment for cancer of the chest or neck
  • family history of lung cancer
  • breathing in highly polluted air
  • having HIV

See your healthcare professional for regular checkups if you have concerns about any of these factors.

Learn some more facts about lung cancer.

How do doctors diagnose SCLC?

Screening for lung cancer can involve a:

Learn more about how doctors test for lung cancer.


The definitive diagnostic tool for SCLC is a biopsy. A biopsy involves taking small samples of the cells that form the tumor. A pathologist then examines the cells under a microscope to see if they have changed into cancer cells and what type. 

Clinicians take biopsies either through needle aspiration or using a small cutting tool. Needle aspiration involves guiding a long, thin needle by ultrasound to the center of the tissue and collecting a small number of cells by pulling on the plunger connected to the syringe and needle.

Find out more about biopsies.

What are the treatment options for SCLC?

Treatments depend on the type and stage of the cancer. Doctors use some standard treatments for all types of lung cancer, while some are specific for SCLC. The type of treatment you have will also depend on your health status and your treatment goals.

Standard treatments include:

Another treatment option is to take part in a clinical trial that is trying out new cancer treatments. 

Find out what to expect from SCLC treatment.

Complementary treatments

People can try complementary, nonmedical treatments alongside conventional treatments, including massage therapy, acupuncture, herbs, and vitamins.

Discuss with your healthcare professional any alternative therapies you wish to pursue. They will be able to advise you on which ones may help and which ones might cause harm.

Learn more about treatments for SCLC.

What is the outlook for SCLC?

Based on research from the American Cancer Society from 2011–2017, the 5-year relative survival rates for SCLC are as follows:

  • Localized stage: 29%
  • Extensive stage, regional: 18%
  • Extensive stage, distant: 3%

A relative survival rate shows how long someone with a specific condition may live after their diagnosis compared with someone without the condition. 

For example, a 5-year relative survival rate of 70% means that 70 out of 100 people diagnosed with a condition are still living at least 5 years from the time of diagnosis.

It’s most important to remember that figures are estimates, and everyone is different. Talk with your doctor about your specific condition.

Learn about stage 4 lung cancer.

Other frequently asked questions

Here are some more frequently asked questions about SCLC.

Is small cell cancer serious?

Small cell cancer is very serious. Symptoms often do not show up until the cancer is advanced. You can decrease your risk of developing SCLC by avoiding those things that cause lung cancer.

Be proactive by seeing your healthcare professional and having all the screenings your doctor recommends. This will increase the likelihood of finding any cancer at an earlier stage.

How do you get small cell carcinoma?

You can develop SCLC by inhaling damaging things into your lungs. Chemicals such as asbestos and exposure to tobacco smoke both cause SCLC. You can decrease your risk by making lifestyle changes, such as:

  • quitting smoking
  • testing your house for radon
  • wearing protective gear if you need to be in an environment with air-borne chemicals

How long can you live with stage 4 SCLC?

Stage 4 SCLC is the final stage and the hardest to treat due to the extent it has spread through your body. The 5-year survival rate for stage 4 SCLC is 3%.

These figures are based on past numbers and are an average of those with SCLC. The treatment and survival rates may have changed, so speak with your oncologist to get more information on these figures. 

Read more frequently asked questions about lung cancer.


SCLC is a cancer of the lungs. Smoking is one of the biggest risks for SCLC, but people who have never smoked can also develop it. Symptoms include wheezing, coughing up blood, and chest pain.

The outlook for SCLC depends on how far the cancer has spread. A doctor will scan your lung and biopsy some cells to diagnose SCLC accurately.

Treatment can involve surgery, chemotherapy, radiotherapy, and more.

Researchers are also exploring new developments in treatments for SCLC in clinical trials.

Was this helpful?
Medical Reviewer: Adithya Cattamanchi, M.D.
Last Review Date: 2023 Feb 2
View All Lung Cancer Articles
THIS TOOL DOES NOT PROVIDE MEDICAL ADVICE. It is intended for informational purposes only. It is not a substitute for professional medical advice, diagnosis or treatment. Never ignore professional medical advice in seeking treatment because of something you have read on the site. If you think you may have a medical emergency, immediately call your doctor or dial 911.