Small Cell vs. Non-Small Cell Lung Cancer

This page explains the difference between the two main types of lung cancer: small cell and non-small cell. It covers how fast each grows, how each is staged and treated, and what to ask your team.

Lung cancer is not one disease. The American Cancer Society says about 80% to 85% of lung cancers are non-small cell (NSCLC). About 10% to 15% are small cell (SCLC). They are told apart under the microscope. That difference affects how fast the cancer grows, how it is staged, and how it is treated.

NSCLC includes adenocarcinoma, squamous cell carcinoma, and large cell carcinoma. The American Cancer Society says these are grouped together because their treatment and outlook are often similar.

NCI describes small cell lung cancer as "a type of fast-growing cancer." NCI says it can grow and spread quickly, often leading to spread to other parts of the body early. The American Cancer Society says it tends to grow and spread faster than NSCLC. It says that in most people with SCLC the cancer has already spread beyond the lungs when it is found. NCI says smoking, now or in the past, is the most important risk factor for lung cancer.

The American Cancer Society also says small cell lung cancer tends to respond well to chemotherapy and radiation. For most people, though, the cancer returns at some point. Shrinkage is common. Keeping it away is the hard part.

NSCLC tends to grow and spread more slowly. NCI says molecular tests, meaning tests for certain genes, proteins or other molecules in a sample of tissue or blood, can help plan treatment.

NCI says SCLC is usually classified into two stages because of its tendency to spread early. Limited stage means the cancer is in the lung where it started. It "may have spread to the area between the lungs or to the lymph nodes above the collarbone." Extensive stage means it has spread beyond that to other places in the body.

NSCLC usually uses the TNM staging system. TNM stands for tumor, nodes, and metastasis (spread). Stages I through IV are based on tumor size, lymph node involvement, and distant spread.

For small cell lung cancer, NCI lists chemotherapy drugs that include carboplatin, cisplatin, and etoposide. It says combinations may be used. In 2019 the FDA approved atezolizumab with carboplatin and etoposide as first-line treatment for extensive-stage SCLC. For extensive stage, NCI lists immunotherapy (atezolizumab or durvalumab) with combination chemotherapy. Immunotherapy means treatment that helps your own immune system attack the cancer.

For limited stage, NCI lists chemotherapy with radiation to the chest. It also lists durvalumab after chemoradiation. In December 2024 the FDA approved durvalumab for adults with limited-stage SCLC whose disease had not progressed after concurrent platinum-based chemotherapy and radiation. That was based on the ADRIATIC trial, where median overall survival was 55.9 months versus 33.4 months with placebo.

NCI says radiation to the brain, to lower the chance that cancer will spread there, may also be given. It lists this for people who had a complete response to chemotherapy. It is called prophylactic cranial irradiation.

For non-small cell lung cancer, NCI lists many targeted therapy and immunotherapy drugs. It says your doctor may suggest biomarker tests to help predict your response to certain drugs. NCI says the choice of treatment depends on the stage and on whether the cancer has gene changes, such as in the EGFR or ALK gene. For SCLC, NCI lists one targeted therapy, everolimus.

NCI states that "for most people with small cell lung cancer, current treatments do not cure the cancer." NCI's clinician summary says a cure is difficult to achieve because SCLC is often widely spread by the time of diagnosis. It says people with limited-stage disease have a better outlook than those with extensive-stage disease. It calls chemotherapy with chest radiation the standard of care for limited stage.

For extensive-stage SCLC that has grown during or after platinum chemotherapy, the FDA first approved tarlatamab in May 2024 under its accelerated pathway. In November 2025 it converted that to a traditional approval.

For NSCLC, NCI says the outlook depends on the stage and on whether the cancer has gene changes such as EGFR or ALK. Ask your team what this means for you.

• Which type do I have? For NSCLC, which subtype?
• Was testing for gene changes and biomarkers done, on tissue or blood? When will results come back?
• For SCLC, is it limited or extensive stage? Has brain imaging been done?
• What is the goal of treatment: cure, or control?

• NCI: Small Cell Lung Cancer Treatment (PDQ) - Patient Version
• NCI: Small Cell Lung Cancer Treatment (PDQ) - Health Professional Version
• NCI: Non-Small Cell Lung Cancer Treatment (PDQ) - Patient Version
• American Cancer Society: What Is Lung Cancer?
• FDA: Durvalumab approved for limited-stage small cell lung cancer (December 2024)
• FDA: Atezolizumab approved for extensive-stage small cell lung cancer (2019)
• FDA: Accelerated approval of tarlatamab-dlle for extensive-stage small cell lung cancer (May 2024)
• FDA: Traditional approval of tarlatamab-dlle for extensive-stage small cell lung cancer (November 2025)
• NCI: Drugs approved for lung cancer