The odds of getting lung cancer are very high if you smoke. In fact, most cases of the disease are associated with smoking. Stopping smoking (if you are a smoker) can be so helpful to cut your risk. This also means that though it is life-threatening, but actually it is preventable.
It has some different types. But it is classified into two main categories; small cell and non-small cell carcinoma.
These two types have different treatments. If you have lung cancer, your doctors need to diagnose the type of this cancer before making the treatment plan.
Small cell carcinoma
The type of lung cancer exclusively found in smokers is small-cell carcinoma. It’s very rare to find non-smokers with this type.
As the name suggests, the word ‘small cell’ refers to shape and size of the cancer cells. This can be closely observed under a microscope.
Like most things in cancer, small cancer carcinoma also starts to develop when healthy cells in the lung get altered and grow uncontrollably. Overtime, these cancer cells form a mass called cancer tumor.
Some common symptoms of small cell lung cancer include:
- Feeling of breathless such as shortness of breath.
- Chest pain.
- Coughing most of the time, and typically difficult to improve. It may come up sputum (thick mucus), or even blood. You may also like to read about the way of how lung cancer causes coughing up mucus!
- Lethargy, including weakness and tiredness.
- Appetite loss which contribute to cause weight loss, too.
However these symptoms may be caused by other underlying causes. Even early small cell lung cancer can have no any symptom!
The bad news, this type is quite quickly to develop and spread. Therefore, it is often caught at advanced and more difficult to treat. Even many cases are diagnosed at metastasis stage, a condition of when cancer has spread to a distant organ.
Lymph nodes within the chest are usually the first places where small cell lung cancer spreads. Because lymph flows toward the center of the chest! And cancer cells usually spread though lymphatic system and bloodstream.
Non-small cell carcinoma
It is the most common type of lung cancer, and even it is also divided into several sub-types. Unlike in small cell carcinoma, non-small cell carcinoma is not exclusively found in smokers (it’s also quite common in non-smokers).
It starts when normal cells of the lung grow and change uncontrollably. Though it has several sub-types, but they can be treated with the similar ways since they don’t behave in different ways.
These sub-types may be based on the kind of epithelial cell where they develop, which include:
- Adenocarcinoma, it starts from cells that make mucus. It is the most common form of non-small cell lung cancer.
- Squamous carcinoma, it starts from cells of the airways.
- Large cell carcinoma, it can start from cells other than two types mentioned above.
For a comprehensive guide about types of lung cancer, see this section!
A risk factor is anything (either factor or condition) that can contribute to increase your risk of developing lung cancer. And as noted before, cigarette smoking is the greatest risk factor.
One of the first evidences for the link between smoking and risk of lung cancer was found in 1950. According to this study, the risk of lung cancer in individuals who smoked about 20 cigarettes per day was 26 times if compared to non-smokers. Those who took 3 cigarettes per day still had about 6 times the risk of this cancer of non-smokers.
Other studies also confirmed the huge risks associated with cigarette smoking! In essence, the more tobacco smoke you inhale, the greater risk of lung cancer you will have!
The smoke of tobacco can damage cells of your lungs and airways! Over time, if you continue smoking, some of these cells may turn into cancer cells. This risk is higher if you smoke heavily or /and for many years.
So, the odd of getting lung cancer is much greater in smokers than general populations. But this doesn’t mean that lung cancer cannot affect non-smokers. Even secondhand smoke (regular exposure to tobacco smoke from someone else) can increase the risk, too.
Smoking (including for small portion of secondhand smoke) has a role in causing about 8 out of 10 cases. In other words, again most patients with lung cancer are smokers and passive smoking.
Therefore after smoking, it’s still important to avoid the exposure to secondhand smoke. Furthermore, there are also other things in environment that can increase the risk. For comprehensive guide to cut your risk of lung cancer after quitting, see also this post!
Smoking is also associated with the increased risk of other cancers (at least 14 cancers – cancers of lung, voice box, upper throat (including mouth), nose & sinus, liver, stomach, pancreas, kidneys, bladder, bowel, ovary, cervix, and some kinds of leukemia).
Overall, it can also affect your entire health. The toxic chemicals from tobacco smoke can enter the bloodstream, and they can spread to other parts of the body (not only in the lungs)!
- The British Medical Journal. 1950; 2(4682):739–48 [Doll R, Hill AB. Preliminary report ‘Smoking and carcinoma of the lung’]