Although death rates due to lung cancer in the US caused by smoking has fallen (by 43 per cent in men and 17 per cent in women since 1990, thanks to decrease in smoking); lung cancer continues to be leading cause of cancer death in both men and women and the second most common cancer overall.
The five year survival rate which is the percentage likelihood of an individual diagnosed with lung cancer surviving for five or more years from the day they were diagnosed.
Types of Lung Cancer:
Bronchogenic Carcinomas are divided into two categories, based on the size of the tumour it represents, namely small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC). The size in question that defines these two categories is on a microscopic level. SCLC is seen in about 20 per cent of the total patients diagnosed of lung cancer. However, it is the most aggressive of the bunch with it most commonly seen in smokers and only 1 per cent of non-smokers. In most cases of SCLC, the cancer is only discovered after it has spread to other organs and tissues. NSCLC on the other hand is relatively more prevalent with about 80 per cent of the total cases being cases of NSCLC. Based on the type of cell found in the tumour, it can be divided into the following subcategories:
Adenocarcinomas: These are usually common in smokers. However they also seen in non-smokers and develop in the outer areas of the lung.
Bronchioloalveolar carcinoma: a subtype of adenocarcinoma, this usually develops at multiple sites in your lung and spreads via the alveolar walls.
Squamous cell carcinoma: Although once more common than adenocarcinomas, they still comprise 30 per cent of the total NSCLC cases and mostly occur in the central chest area in the bronchi.
Large cell /undifferentiated carcinomas: Least common NSCLC.
Mixtures: different types of NSCLC in one.
Besides SCLC and NSCLC there are other cancers which are not as common as both of them, however they comprise 5 per cent-10 per cent of the total cases:
Bronchial carcinoids: Seen mostly in individuals of forty years and younger, these tumours are small: about three to four cm and can metastasize with a few of them secreting hormone-like substances which may showcase specific symptoms common to that hormone. If detected early enough, it can be cured via surgery.
Cancers originating on supporting lung tissue.
If your doctor feels that you run the risk or are exhibiting symptoms common to lung cancer, he/she might want you to run a few tests so that he can target your specific case and work to cure it effectively.
Imaging Tests: With the help of an X-ray, your doctor may be able to assimilate the area and extent of your cancer as it may reveal itself in the form of an abnormality. Smaller lesions can be found with the help of a CT scan as an x-ray may fail in that case.
Sputum Cytology: If you’re producing sputum along with excessive coughing, an analysis of it could reveal the presence of a cancer.
Tissue Sample (biopsy): Taking a sample from the cancerous region with the help of a needle and analysing it.
Once diagnosed, the next step is to stage the cancer. This gives the doctor a brief idea as to what kind of medication or treatment is right for you. Your case may fall under the following stages:
Stage I: The tumour is less than two inches in size and the cancer is limited to the lungs without it having spread to the neighbouring lymph nodes.
Stage II: There are two conditions that may qualify a cancer to be stage II namely if the tumour is larger than two inches or has a smaller tumour that has involved nearby structures like the chest wall, the lining around the lungs or the diaphragm. It may or may not have spread into the lymph nodes.
Stage III: The cancer has grown large and has affected neighbouring regions or smaller tumours have developed in lymph nodes further from the lungs.
Stage IV: Cancer has spread beyond the lungs to either the unaffected lung or any other distant tissue or organ.
Based on all the information gathered by your doctor via your tests and understanding the stage of your cancer, your treatment option may include one or more of the following:
Surgery: In a surgery, your surgeon may remove the cancerous region in your lungs along with a margin of healthy tissue. A surgical procedure is usually apt for early stage NSCLC ,given it’s relatively non-aggressive nature and its likelihood of effectively removing the most of the cancer from the lungs. The kind of surgery performed is based on which part of the lung is affected by the cancer:
Lobectomy: The lungs are divided into lobes: regions divided by fissures. There are a total of five lobes: three in the right lung and two in the left, meaning that each lung is different from the other. If the cancer is limited to just one lobe of one lung, then a lobectomy is performed, which involves removal of the affected lobe. Similarly, Bilobectomy: Involves the removal of two lobes.
Pneumonectomy: Involves the removal of the entire lung in cases where the cancer is located in the center of the lung or has affected two lobes of the left lung or three lobes of the right lung. A common misunderstanding about this procedure is that the patient will have breathing issues, thanks to the smaller area of the lung. However, no such instance has been proved.and breathing is shown to be unaffected. Also, doctors would evaluate your breathing patterns before you are recommended the procedure.
Wedge Resection: If the doctor feels that the patient may compromise breathing a lobectomy and the cancer is limited to a small part in the lung, then a wedge resection is performed where only the affected part of the lung is removed (generally much smaller than a lobe) along with the surrounding tissue. However, unless there is a breathing issue is a wedge resection performed as there’s a high risk of recurrence of the cancer again.
Segmentectomy: Another alternative to a lobectomy, in cases where it cannot be performed due to a patient’s specific case, then a segmentectomy is performed. The lobes are further divided into segments: these segments are the ones that are removed during a segmentectomy.
Chemotherapy: Main purpose is to kill cancer cells. Usually used after a surgery to kill remaining cancer cells. Involves the use of chemotherapy drugs injected into the bloodstream via a vein or orally. Treatment lasts for weeks or months, with gaps in between to allow the patient to recover. Chemotherapy is usually not region specific and tends to be able to cover the entire body and combat cancer cells that may arise anywhere. This feature is especially effective with regard to SCLC which is known to metastasize faster and to different parts of the body.
Targeted drug therapy: Makes use of drugs designed to combat certain complications of cancer. Though it may seem that it overlaps with chemotherapy, that isn’t the case as unlike chemotherapy, these drugs are designed to affect certain features of a cancer cell. The drugs thus used are differentiated on the basis of which function or part of the cancer cell it affects:
Angiogenesis- drugs that affect the blood supply of the tumour.
Drugs that affect the epidermal growth factor receptor, a protein found on the tumour that is in charge of signalling the cells to divide and multiply. These drugs inhibit it to receive the signals thereby limiting the tumor.
Drugs aimed at cases with ALK gene rearrangement, most commonly seen in smokers.
These drugs come with their own specific side effects. Though they may not be as intense as those seen in chemotherapy or radiation therapy, it may still be present and may include: nausea, vomiting, fatigue,skin sores, diarrhea etc.
-Cancer Council. A Brief History of Smoking. CancerCouncil.com.au. [Online] [Cited: 09 May 2017.]
-Cancer.net. Lung Cancer – Non-Small Cell: Statistics. Cancer.net. [Online] [Cited: 09 May 2017.]
-MedicineNet.com. Picture of Lungs. MedicineNet.com. [Online] [Cited: 09 May 2017.]
-Hoffman, Mathew. Picture of the Lungs. WebMD.com. [Online] [Cited: 09 May 2017.]
-Medical News Today. Lung Cancer: Facts, Types and Causes. MedicalNewsToday.com. [Online] [Cited: 09 May 2017.]
-Stöppler, Melissa Conrad. Lung Cancer. Medicinenet.com. [Online] [Cited: 09 May 2017.]
-Mayo Clinic Staff. Tests and diagnosis. MayoClinic.org. [Online] [Cited: 09 May 2017.]
-Treatments and drugs. MayoClinic.org. [Online] [Cited: 09 May 2017.]
-TreatMyLungCancer.com. Understanding Your Surgical Options For Lung Cancer. [Online] [Cited: May 23, 2017]
Lung cancer has no specific symptoms: it depends on the extent of the cancer and where it is. In some cases it might exhibit pain in the patient; in others the patient won’t even realize the presence of lung cancer until he/she is diagnosed of it during a routine check-up. However, the possible symptoms can be narrowed down, along with its respective reasons, as follows:
No symptoms: As mentioned earlier, lung cancer may not reveal any kind of symptoms unless during a routine check-up. In an X-ray or MRI the tumour turns up as a coin shaped image giving it the name ‘coin lesion’.
Cancer related symptoms: This is based on where the cancer has affected: for instance if the cancer affects the surrounding lung tissue, it may lead to breathing problems, if it affects the nerves, then it could either lead to shoulder pain or hoarseness of the voice due to paralysis of the vocal cords. Finally, if it affects the oesophagus, it could lead to trouble swallowing.
If cancer has metastasized to other parts of the body: For example if the cancer has spread to the bones, it could cause intense pain and stress at sites of bone involvement.
Para-neoplastic symptoms: Sometimes, lung cancer may be accompanied by symptoms that are due to the production of hormone like substances by the tumour cells.
Though no formal cause has been found to cause cancer, it can be instigated by the following two reasons:
Carcinogens: These are substances directly attributed to contributing to cancer by damaging the cells. An ideal example of carcinogens with respect to lungs is those suspended in tobacco smoke: 87 per cent of the total cases of lung cancer have been attributed to smoking and exposure to secondhand smoke.
Genes: An individual’s genetic makeup might be such that he is more likely to develop lung cancer later in the future either directly or by being instigated by external environmental factors like pollution.
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