Lung cancer is slowly becoming the top cause of cancer related death in India and Asia. This cancer most often occurs in people who smoke. Although, there is a growing population of patients without smoking or tobacco history developing lung cancer.
Lungs are a pair of spongy organs in the chest, which enable exchange of gases. During inspiration, the air enters through the mouth and nose and reaches the lungs through the windpipe. The windpipe called trachea further divides into small tubules called bronchi, which further divide into smaller branches called bronchioles. The bronchioles further divide into tiny air sacs.These air sacs are known as alveoli.
In lung cancer, the cell linings of these structures- the bronchi, the bronchioles or the alveoli, start to divide at a very high speed and thereby a tumour forms which creates problems in normal breathing
There are two main types of lung cancers based on how the cancer cells look like. These are:
- Small cell carcinoma
- Non-small cell carcinoma
About 80- 85% of lung cancers are non-small cell lung cancer abbreviated as NSCLC. Their subtypes are as follows:
- Squamous cell carcinoma
- Large cell carcinoma
This division is made on the basis of different types of lung cells. Their treatment and prognosis are also similar.
Adenocarcinoma: This starts in the cells that would normally secrete mucus. It is found in the outer parts of the lungs where it is usually noticed before it spreads. Therefore, when it is in the early stages confined to one layer, it is called adenocarcinoma in situ.
Squamous cell carcinoma: The flat cells which line the inside of the airways are called squamous cell and carcinoma involving these cells is known as squamous cell carcinoma. They are found in people who have a history of smoking and tend to be found in the central part of the lungs near the main bronchus
Large cell carcinoma is the undifferentiated type. Large cell carcinoma tends to grow and spread very fast and it can appear in any part of the lung. Therefore, its treatment is very difficult. It has the following subtypes:
- Neuroendocrine carcinoma
- Adenosquamous carcinoma
- Sarcomatoid carcinoma.
Small cell carcinoma is 10-15% of all lung cancers and is called fat cell carcinoma. By the time these cancers are diagnosed, they have already spread in about 70%of cases. This is the reason it responds well to chemotherapy and radiation therapy. However, recurrence is high.
Symptoms vary depending on whether the disease is in its early or late stage. The symptoms are similar to other diseases of the lung.
Coughing allows your body to expel irritants from throat or airway by pushing air in and out of lungs. If the cough is worsening and intense and it is not responding to treatment then go ahead with the checkups with the doctor to rule out cancer. Hemoptysis is coughing of blood, or coughing out mucus should be investigated.
Dyspnea is shortness of breath. There is tightness in the chest. Large tumours or even cancerous spread can cause blockages in major airways leading to a collection of fluid in and around the lungs. This is called pleural effusion.
Wheezing is a high-pitched whistling sound made while breathing in and out.
Hoarseness or change of voice. This is caused by the opening and closing of the vocal cords, which produces vibrations.
Chronic fatigue - Fatigue is a constant worn-out feeling. When the body is continuously trying to fight the attack of cancer, it drains out energy from the body making the body feel lethargic.
Fever - This is another symptom trying to indicate that the body is fighting back infection, Temperature above normal if persists for long and does not go away with treatment then you should seek the attention of a doctor.
Swelling or edema - This symptom appears when tiny blood vessels or capillaries in your body are damaged and undergo pressure and fluid is leaked out. The kidneys, in turn, retain water and salt to compensate for the loss thus in turn causing more swelling.
Enlarged lymph nodes - These are multiple swelling in the body neck, face and arms. The cancer cells can block the lymphatic drainage thereby causing swelling.
It is important to note that symptoms of lung cancer are similar to symptoms of other lung diseases. Keep reading to learn what these symptoms are. If you experience any of them, you should see your doctor for a medical evaluation.
Other symptoms of lung cancer
Other symptoms that may present in the case of lung cancer are:
- Pain in the shoulder or back
- Chest pain
- Frequent attacks of pneumonia and bronchitis
- Unexplained weight loss
- Loss of appetite
As soon as you are suspicious of having any symptoms that might be similar to symptoms of lung cancer, you should immediately consult our doctor. Your medical history will be evaluated, risk factors will be weighed if any, and physical examination will be done. Then, our doctor will decide whether you require special tests.
What specialists treat lung cancer?
Lung cancer is typically treated by team of specialists comprising of Thoracic Surgeon, Medical Oncologist, Pulmonologist, Interventional Radiologist and Pain/Palliatve Care specialists.
Physical examination: Our doctor will check the vital signs like oxygen saturation, heart rate and blood pressure. Auscultate for lung sounds, look for lymph nodes. This physical examination may reveal the presence of signs and symptoms related to lung cancer.
X-Ray: A Chest XRay PA view or postero-anterior view or X-Ray view from back to the front of the chest wall reveal the suspicious area in the lung. Lateral view or view from the side also is the diagnostic step to reveal lung cancer symptoms.
CT scan: Computerised tomography scan means taking internal pictures as it rotates around your body. This will give a detailed image of the internal organs.It can help to identify tumours or cancers better than standard X-rays. CT scan of chest, abdomen and brain can be done to examine for primary and metastatic lung tumour.
Bronchoscopy: This is an endoscope used to examine bronchus and lungs. In this, a thin lighted tube is used to insert through the mouth into the lungs. This can be used to take a biopsy or take out a few cells for examination. It is easier to take samples from the large tumours. It is done as an outpatient department procedure. The procedure can be done under sedation or anaesthesia.
EBUS – Endobronchial Ultrasound: This is a special type of endoscope where in addition to the camera at its tip, there is an Ultrasound probe which helps see through the wall of the airway and guide the passage of the biopsy needle to obtain samples. It is easier to take samples from the large tumours. It is done as an outpatient department procedure. The procedure can be done under sedation or anaesthesia.
Sputum cytology: It is the thick mucus expectorated during coughing. If this sputum is examined by a pathologist under a microscope, he will be able to diagnose malignant cells thus confirming the diagnosis of lung cancer. Although the limitation of this test is that not necessarily the malignant cells will be present in the sputum.Also, non-cancerous cells due to inflammation mimic cancer cells.
Magnetic Resonance Imaging: This technique uses magnetic radio waves and a computer to produce images of body structures. A movable bed is put into the magnetic scanner enabling the detailed view of the tumour's location. But due to the magnetic attraction people with heart pacemakers, metal implants, artificial heart valves and other surgical implants cannot be examined. MRI Brain completes the workup of Lung cancer as it may be affected in many patients.
Positron emission tomography scan: Pet scan is a specialised imaging technique which uses short-lived radioactive drugs to produce three-dimensional coloured images. It measures metabolic activity and the function of tissues. It helps to determine the growth of the tumour and as well as the type of tumour. The radioactive drug accumulates in certain tissues and emits positrons. As the positron encounters electrons, a reaction producing gamma rays occurs. A scanner records these gamma rays and maps this particular area.
Blood tests: This reveals the biochemical or metabolic abnormalities in the body that accompany cancer. In bone cancer, calcium levels are elevated as well as serum alkaline phosphatase is increased. Liver enzymes SGOT and SGPT signal liver damage.
Molecular testing: Molecular genetic testing to look for genetic mutations in the tumour. These mutations can be looked for in the epithelial growth factor receptor and the anaplastic lymphoma kinase genes. MAPK and PIK 3 are genes that mutate. Specific therapies are given to these patients whose tumours have these gene alterations.
Lung biopsy: Imaging tests might help,but biopsy is the most confirmatory test for the diagnosis of cancer. This will also enable us to know the type of cancer.
Lung cancer can be caused by various factors or a combination of them. These factors include:
Genetics: According to studies, if any of your immediate family members has lung cancer, then you have a higher risk of developing the disease. Changes in the DNA can lead to cells to become cancerous. However, how other risk factors cause the DNA to change is uncertain. These DNA changes can be inherited or acquired during a lifetime from exposure to various factors.
Age: The risk of lung cancer increases with age.
Past lung diseases: Exposure to other lung diseases such as tuberculosis or bronchitis can cause inflammation and scarring of the lungs. This increases the risk of cancerous growths.
Exposure to radiation or radiation therapy.
Smoking: Smoking tobacco, cigar, etc. can increase your chances of having lung cancer. These smokes contain substances, which are carcinogenic in nature. As soon as your body is exposed to these carcinogens, the cells start to degrade. Initially, your body can repair these changes but continuous exposure weakens the body’s immune system. It is the leading cause attributing to 80% of fatal cases.
Tobacco chewing:In India, this is very common, contributing to increased number of lung cancer patients.
Passive Smoking: It is the exposure to second-hand smoke (from an active smoker). It can occur at work, home or public places.
Diet: An unbalanced diet, which does not provide your body with all the required vitamins and minerals can put you to a risk of cancer.
Environmental factors: Certain environmental factors that can put a person at the risk of lung cancers. These factors include
- Exposure to Radon: Radon is a naturally occurring radioactive gas, which is a result of Uranium breakdown in the soil.
- Exposure to Asbestos: This is an industrial material used as a construction material or a fire retardant.
- Arsenic in drinking water is associated with higher risks of cancer.
- Air pollution: According to studies, 5% of fatal lung cancers worldwide are a result of air pollution.
Lung cancer treatment depends on the “Stage” of disease as treatment strategies vary according to the extent of disease spread. The following are the tests which are mandatory for the treatment of lung cancer.
- PETCT scan
- EBUS TBNA/Mediastinoscopy
- CT/MRI Brain
All the above tests are available and performed on a routine basis at our centre.
Thangam Cancer Center has a dedicated Thoracic Oncology Unit with all specialists and investigations necessary for the treatment of lung cancer.
Surgery: A surgical procedure- called lobectomy may be required to remove the cancerous tissue from lungs may be required. This may involve removing a part or segment of lung or the entire lung, depending on severity. In addition to removal of the involved lung tissue, lymph nodes also are systematically harvested to gain addition survival advantages.
Chemotherapy is a treatment given through the veins, to kill cancer tissue that may have escaped into the bloodstream and spread to other parts of the body. It is given in the following three settings:
- Neoadjuvant: Chemotherapy is given prior to surgery or radiation to downsize the cancer.
- Adjuvant: Chemotherapy is given after surgery in this situation.
- Palliative chemotherapy: This is given in patients who are in Stage IV (very advanced cancer) to relieve them of symptoms and improve
Radiation therapy is used in select groups of patients either in “adjuvant”, “neoadjuvant” or “definitive” settings. In addition, in patients where the disease has spread to the bone, it helps in alleviating pain.
Targeted therapy This treatment has revolutionized the treatment of advanced lung cancer, where drugs specifically “target’ cancer cells and relatively spare other cells. This has changed the landscape of treatment of lung cancer
Immunotherapy: Recent improvements in drug development has led to the introduction of “immune boosting” drugs, which in effect stimulate the body’s immune mechanism to fight against and kill cancer cells. It is an exciting concept that may change the landscape of lung cancer management.
Not all lung cancers can be prevented. However, you can take care of the following to reduce the risk.
- Quit smoking.
- Eat a healthy diet
- Exercise regularly. Consult our specialists for breathing exercises that will help you stay fit and healthy