Stage I Non-Small Cell Lung Cancer

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

Symptoms may be missed with early-stage lung cancer, so it's important to be aware of signs that indicate lung disease and be aware of the risks of developing cancer. If your doctor does catch 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 or carcinoma-in-situ. In most cases, the disease isn't identified until it is in the advanced stages.

Only about 12% to 15% of non-small cell lung cancers are detected when they're still at stage I, according to a study of British patients. This may vary, but it's still clear that lung cancer is often missed when tumors are so small that they don't interfere with someone's day-to-day functioning.

Your oncologist might describe the stage of your cancer based on something called 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 bronchi

T1c, N0, M0

Between 2 cm and 3 cm
•Has not reached the membranes around the lungs
•Doesn't affect the bronchi  

T2a, N0, M0

•Between 3 cm and 4 cm
•Meets one or more of the following criteria:

1) Has grown into a main bronchus, but is not within 2 cm of the point where the windpipe splits to main bronchi
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 your doctor noticing something incidentally on an X-ray that was performed for another reason. If you're particularly at risk for lung cancer, though, a doctor might order a computed tomography (CT) screening to monitor you for the disease.

It's less common for a diagnosis to result from you or your doctor noticing stage 1 lung cancer symptoms. However, in some instances, people do develop common symptoms early on.

These may include:

Since the cancer has not spread in stage 1, symptoms such as major fatigue, unintentional weight loss, or significant pain are usually not present.

When there is no reason to suspect lung cancer, physicians often miss the subtle signs of a problem. In fact, a third of people diagnosed with lung cancer visit their doctor three or more times with symptoms that are related to cancer before being accurately diagnosed.


Stage 1 lung cancer is localized, meaning it has not spread to any lymph nodes or other organs. This factors into the treatments your doctor can consider.


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 one's general health.

If surgery is recommended, the tumor will be removed through one of three types of procedures:

  • Wedge resection (segmental resection): When a tumor is caught very early, a wedge resection for lung cancer may be performed. This involves removing a wedge-shaped portion of the lung that lets doctors take out the 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.

These procedures can be done in one of two ways. Doctors may perform an open chest thoracotomy, which requires a large incision across the chest and the ribs to be pulled back to allow the doctor to access the lungs.

The second option is a video-assisted thoracoscopic surgery (VATS): This is a less invasive procedure in which small incisions are made and instruments with a video camera are inserted to allow the doctor to remove 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, depending on where the tumor is located, VATS instruments may not be able to reach the mass.

Chemotherapy may be used after surgery as an adjuvant treatment to ensure all cancer cells have been destroyed. However, the benefits 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, which delivers high-energy radiation directly to 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 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 was 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, the 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 poorer once the cancer has metastasized to these locations.

In those who have smoked in the past, there is also a risk of developing a second primary tumor 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, and a stage 1 diagnosis is just that. 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 looking at new ways to help lung cancer patients lead long, healthy lives.

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