How fast does lung cancer grow & FAQ's


Lung cancer is a prevalent type of cancer. National Cancer Institute (NCI) stated that in 2020, approximately 229,000 people in the US received a lung cancer diagnosis. 

The risk of lung cancer depends on the type, the stage at diagnosis, and overall health. Lung cancer is the reason for more than 1 in 8 new cancer cases. The speed at which lung cancer develops grows and spreads; will be explained in this article.  

How fast does Lung Cancer Grow & other FAQ’s’ will be discussed below.

Lung cancer

Lung cancer is limited when it has not spread past the lungs. Over time it will spread to other parts. The survival rate for localized lung cancer is 5 years. 

 Some of these FAQ’s are:

  • Can we wait for genetic testing results before starting treatment?
  • Is there time to undergo pulmonary rehabilitation before lung cancer surgery?
  • Is it OK to wait and observe lung nodules for the time being?
  • What does the size of your cancer mean?
  • How fast does lung cancer grow?

Accepting a diagnosis of lung cancer is difficult. A person may have many questions and we’d like to answer these basic questions. 

How fast does lung cancer grow?

Lung cancer has two types: small cell lung cancer (SCLC) or non-small cell lung cancer (NSCLC). How fast does lung cancer grows, differ for both types? 

NSCLC is widespread and around 85%  of lung cancer cases belong to this type. SCLC is found rarely but it spreads rapidly. Doctors often diagnose SCLC at a later stage. Sadly 57%  of all lung cancers have spread beyond the chest by the time a doctor diagnoses this.

Cancer is Different for Everyone

It’s crucial to perceive that each person is different, and so is every cancer. Two lung cancers of the same type may act differently. Each cancer grows at a varying rate. Sometimes the growth rate might seem similar but, you still need more information to make decisions.

How does lung cancer spread?

To know whether or not lung cancer has spread, the following tests are done:

  • blood tests
  • chest X-rays
  • MRI scans
  • CT scans
  • PET scans
  • bone scans

These tests help to know whether the cancer is localized to the lungs & chest or has spread to other areas.

Where does lung cancer spread first?

In the early stages, it spreads to nearby lymph nodes. However, it may be within the chest cavity. After some time, lung cancer may increase through metastasis. The common sites in the body for metastases to occur are:

  • the liver
  • the brain
  • the bones
  • the adrenal glands in the kidneys

Lung cancer cells can spread: to nearby tissue, throughout the body via blood vessels/lymphatic system.

Lung Cancer Cell Growth

A normal lung cell turns into a cancer cell, after a series of mutations in growth control genes. that control cells. So, after this, the cell doesn’t work as usual. Genetically the changes don’t occur immediately. It adds up for a long span of time, even decades. Lung cancer can go undetected by a chest X-ray. As a result, the cells keep on growing.

Growth Rate Differs at Various Stages

Tumour growth may vary during different stages in the cancer cells. Tumours cells undergo new mutations that change them. These new mutations make their cancers oppose treatment that worked earlier. Some new mutations in a tumour may make cancer cells multiply more quickly.

What is a Specific Growth Rate?

Scientists take into account, tumour doubling time and specific growth rate, to estimate how fast a tumour spreads. The specific growth rate is estimated as the change in mass of a tumour in a specific time. This helps to know how much a tumour will spread. For example its daily growth.

What is Lung Cancer Doubling Time?

Physicians define doubling time as, the period of time it takes for a tumour to double in size. But there are more limitations. That’s because of limited: access for research, tumour estimation and incorrect model growth rate.

A study correlating the doubling time of breast cancer with that of NSCLC; discovered that lung cancer (134 days) spreads faster than breast cancer (252 days).

Factors Affecting Growth Rate

Various factors may affect the growth rate of lung cancer, they are:

  • The type & subtype of lung cancer
  • Smoking status
  • Genetic mutations ( EGFR )
  • Methods used to diagnose the tumour
  • Differentiation between men & women

How long does it take lung cancer to spread to other parts of the body?

It depends on the type of lung cancer. Any lung cancer (other than stage 0 lung cancer or noninvasive) can spread.

How long can a person survive without treatment?

Currently, it is impossible to calculate this answer. Without proper treatment, survival is bleak. Studies of 2013 found that the survival time for people with NSCLC, without treatment is over 7 months. And survival time for untreated SCLC is between 2–4 months.

What are the things to consider before opting for treatment?

Physicians provide benefits & risks of getting treatment. They consider the following factors:

  • what type and stage of lung cancer the person has
  • their age & overall health
  • their personal likings

Treatment can improve survival but can cause side effects that lower quality of life.

 Lung Cancer Survival Without Treatment

When Does Lung Cancer Arise?

There isn’t a definite answer, but there are some speculations. One concept is to look at the models of mutation. 

When Is Lung Cancer First Detected?

Sadly, most individuals have an advanced-stage tumour when they are diagnosed.

The average size at which lung cancers can be detected, on a chest X-ray is 10 mm to 20 mm. But on chest CT, tumours as small as 6 mm and sometimes 4 mm) can be seen.

Can we get treated before the test results show up?

In a few cases, waiting a month for test results may lead to better results. That’s more effective with targeted therapies. Targeted therapy is a type of cancer treatment that uses drugs or other substances to accurately find and attack certain types of cancer cells.


Lung cancer is treatable in the initial stages. But early diagnosis is uncommon. Early diagnosis and treatment for lung cancer improve survival rates. The causes are unknown. The American Lung Association estimated that over 12,000 lives could be saved by increased screening for lung cancer. Especially in people who have a high risk, like those who smoke. We hope that your questions like, ‘How fast does lung cancer grow?’ and other general doubts are clarified.