Stage I Non-Small Cell Lung Cancer

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Stage 1 non-small cell lung cancer (NSCLC) is the designation given to this type of lung cancer when tumors are very small and haven't spread. If you're diagnosed at this point in the disease, your prognosis is very good.

There might not be obvious symptoms with early-stage lung cancer, so it's important to be aware of subtle signs of advancing disease. If your doctor catches the disease before it has progressed beyond stage 1, you'll have several treatment options and there's the possibility for a cure.


An Overview of Staging For Non-Small Cell Lung Cancer


In very rare instances, lung cancer may be detected before stage 1 when it's considered stage 0 lung cancer, also described as carcinoma-in-situ. In most cases, lung cancer is not diagnosed when tumors are so small that they don't interfere with someone's day-to-day functioning, and this disease usually isn't identified until it is in the advanced stages.

Only about 12 to 15% of NSCLCs are detected when they're still at stage I, according to a large study.

Your oncologist might describe the stage of your cancer based on the TNM system, where T stands for tumor size, N stands for lymph nodes, and M stands for metastasis (the spread of cancer). According to the TNM system, stage 1 lung cancer can be designated as either stage 1A or stage 1B, depending on how advanced it is.

Stage 1 Lung Cancer
Stage T, N, M Designation Tumor Size and Lung Involvement
T1mi, N0, M0
Minimally invasive adenocarcinoma no more than 3 cm
Part in lung tissues is no more than ½ cm
T1a, N0, M0
No more than 1 cm
Has not grown into the membranes that surround the lungs
Does not affect the main branches of the bronchi 
T1b, N0, M0
Between 1 cm and 2 cm
•Has not reached the membranes around the lungs
•Doesn't affect the main branches of the bronchi
T1c, N0, M0
Between 2 cm and 3 cm
•Has not reached the membranes around the lungs
•Doesn't affect the main branches of the bronchi  
T2a, N0, M0

•Between 3 cm and 4 cm OR
•Meets one or more of the following criteria:
1) Has grown into a main bronchus, irrespective of the distance to the carina    
2) Has grown into the membranes surrounding the lungs
3) Partially clogs the airways

In each of these, there is no spread to lymph nodes or other parts of the body (metastases).


If you're diagnosed with stage 1 NSCLC, it's often the result of an incidental finding on an X-ray that was done for another reason. If you're at risk for lung cancer, though, your doctor might order a computed tomography (CT) screening to screen you for the disease.

While symptoms aren't common, they can include:

Since stage 1 cancer is localized and small, it doesn't usually cause fatigue, unintentional weight loss, or significant pain.

When there is no risk of lung cancer, physicians can miss subtle signs of this disease. In fact, a third of people who are eventually diagnosed with lung cancer visit their doctor three or more times with symptoms that are related to cancer before being accurately diagnosed.

doctor team x-ray
utah778 / Getty Images


The stage of cancer is a major factor in the determination of the right treatment.


Surgery is the treatment of choice for stage 1 lung cancer. However, it may not be possible in some cases due to the location of the tumor or if you can't tolerate surgery due to your baseline general health.

If surgery is recommended, your tumor will be removed with one of three types of procedures:

  • Wedge resection (segmental resection): This involves the removal of a wedge-shaped portion of the lung that includes the whole tumor and some surrounding tissue.
  • Lobectomy: The right lung has three lobes and the left lung has two lobes. A lobectomy involves removing one of the five. It's the most common surgery used to treat lung cancer.
  • Segmentectomy: The lobes of the lung are divided into segments. One of these segments may be entirely removed, along with a tumor, to ensure the cancer cells are eradicated.

Your doctor may do your surgery with an open chest thoracotomy. This surgery requires a large incision across your chest, and your ribs would be pulled back so your doctor can directly access your lungs.

A video-assisted thoracoscopic surgery (VATS) is a less invasive procedure. Small incisions are made and video-equipped instruments are inserted for removal of the tissue without fully opening the chest.

Recovery is quicker with VATS, which is an advantage. However, not all doctors perform this type of surgery, and VATS instruments may not reach the tumor if it isn't accessible with a small incision.

Chemotherapy may be used after surgery as an adjuvant treatment to improve the chances that all cancer cells have been destroyed. However, the benefits of adjuvant therapy are not very high and may put you at risk for other health risks, so the therapy remains controversial.


Another localized treatment option is radiation therapy, in which high-energy radiation is aimed towards the cancer cells to kill them and shrink tumors. This may be recommended if your tumor is considered inoperable.

A specialized type of radiation treatment known as stereotactic body radiotherapy (SBRT) is becoming increasingly popular. Also known as a cyberknife procedure, SBRT can target small areas with high doses of radiation.


Survival rates are better for those who are able to undergo surgery to remove all of the cancer. For stage 1, the five-year survival after surgery is around 80%, versus about 40% for SBRT alone.

Survival rates may be better for those whose cancer is asymptomatic and is first found via a CT screening. Thus, efforts to improve early screenings could help ensure a better prognosis for lung cancer patients.


Even with successful surgery, stage 1 lung cancer can recur—either locally or at distant sites.

It's estimated that lung cancer will recur in 30 to 50% of patients who were treated for stage 1 lung cancer. Most often, recurrent cancer will not appear at the same site as the primary tumor, but at distant sites such as the brain, bone, or liver. The prognosis is much worse if lung cancer metastasizes to these locations.

In those who have smoked in the past, there is also a risk of developing a second primary tumor that's related to smoking, either in the lungs or in other regions of the body.


Today's treatment options offer very successful outcomes when lung cancer is caught early, while it's in stage 1. Don't allow yourself to be discouraged by "what ifs" related to recurrence or progression. Concentrate on working with your doctor to choose the right course of treatment.

You might also want to consider getting a second opinion to be sure that nothing has been overlooked, as well as learning about clinical trials that are constantly examining new ways to help lung cancer patients lead long, healthy lives.

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