If Lung Cancer Is In One Lung Or Two Lungs!

Lung cancer in both lungs means it is categorized into stage IV (metastasis stage, a condition of when the cancer has spread). If cancer is still in one lung, this can be interpreted in many different ways from stage I to stage IV, depending on how far the cancer tumor grows and spreads!

Lung cancer in both lungs

If the cancers have been found in two lungs, it can definitely point to metastasis phase (stage IV) of lung cancer. For such case, the disease is more difficult to treat since there are a few kinds of treatment options you can take.

image_illustration387For instance, a local treatment usually has high successful rate to help treat early lung cancer (when it has not spread yet).  Even for very early stage of lung cancer, a surgery can completely remove the cancer and it’s less likely to come back.

But if it has become advanced, a local treatment is often not effective. For such case, it’s usually treated by systemic treatments that can circulate throughout the body such as radiotherapy, chemotherapy, hormone therapy, etc.

For summary, stage IV means that the cancer:

  1. Is already found in both lungs.
  2. Or has spread to another distant organ of the body such as liver, bones, brain, and adrenal glands.
  3. Or it has caused fluid accumulation containing cancer cells around the lung or heart.

Unfortunately, it’s usually impossible to cure stage IV lung cancer. The goals of the treatments are more intended to help control the cancer, improve the symptoms, and maintain the quality of life of patient.

Overall, the prognosis and outlook of stage IV is the worst scenario. The bad news, lung cancer is often caught lately (many times it is diagnosed at stage III and IV). That’s why the mortality rate from the disease is very high. Even it ranks first in causing death due to cancer.

Lung cancer in one lung

If the cancer is found in one lung, this can be interpreted in many stages, from stage I to stage IV (depending on the size of the cancer tumor and how far it has spread).

The following are possible conditions for lung cancer in one lung.

Stage I

The cancer is still completely in one lung, small in size, and there is no any lymph node affected! Depending on the size of the tumor, stage I is classified into two groups:

  1. Stage IA, when the size of tumor is smaller than 3 cm.
  2. Stage IB, if the size of tumor is about 3 to 5 cm. The cancer cells may have affected the nearby structures such as pleura (membrane covering the lung) or bronchus. The affected lung may also be partly collapsed.

Stage II

This can be divided into two groups, stage IIA and IIB.

Stage IIA means the size of tumor is about 5-7 cm without any lymph node affected – or – the tumor is less than 5 cm but it has affected the nearby lymph nodes. In either case, the affected lung may have partly collapsed or cancer cells may have been found in the structures close to the affected lung such as pleura or bronchus.


*Image credit to Cancer Research UK

Stage IIB means one of the following conditions:

  1. The size of cancer is less than 7 cm without any lymph nodes affected.
  2. No cancer cells are found in lymph nodes, but they may have been found in one or some of the following structures; chest wall, nerve (phrenic), the lining of the heart, or diaphragm (muscle under the lung).
  3. The cancer is found in the main bronchus, where this main airway divides to go to each lung.
  4. It has caused a partial lung collapse.
  5. Or it is in any size but more than one tumor is found in the same lobe of the affected lung.

Stage III

This stage also means a number of different things. In essence, it is more advanced than stage II. But it is still categorized into locally advanced stage, which means there is still no metastasis (no any cancer found in distant organ).

The cancer is still found in one lung, but the size of the tumor can be bigger and it has spread further than what we find in stage II. Even the affected lung may have been completely collapsed.

Stage IV

Cancer in one lung can be categorized into stage IV if:

One Response
  1. Sue Schertz May 30, 2022 Reply

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