Common Cancers – Lungs

Lung Cancer is one of the most common cancer amongst men in India, after head and neck cancers which are common in both sexes.

Lung, a part of the respiratory system helps us to breathe. Lungs are a pair of sponge like cone shaped organ in the chest cavity. The right lung has 3 sections called lobes, it is larger than the left lung which has only 2 lobes. When we breathe in, the lung takes in oxygen and when we breathe out, carbon-di-oxide which is a waste product of the body is expelled.

What is Lung Cancer?

Cancer is an unwanted purposeless and unchecked growth of any body tissue, with a capability of spreading to other areas. Cancer that begins in the lung is called lung cancer. There are four major types of lung cancer, which fall under 2 broad groups.

Small Cell Lung Cancer or Oat cell cancer (less common).
Non Small Cell Lung Cancer (more common).
Squamous cell (Epidermoid Cancer).
Large cell carcinoma.

Who is at risk ?

Researchers have discovered several causes for lung cancer, most are related to the use of tobacco. Smoking of Cigarettes; Biddies; Cigars; and Pipe. Harmful substances (carcinogens) in tobacco damage cells in the lungs, the damaged cells may become cancerous. Over a period of time stopping smoking greatly reduces a person’s risk from developing lung cancer. Environmental Tobacco Smoke or passive smoking also increases the chance of developing lung cancer.

Asbestos – Asbestos is the name of a group of minerals that occur naturally as fibers and are used in certain industries. Asbestos fibers tend to break easily into particles that can float in the air. When these particles are inhaled, they can lodge in the lungs, damaging cells and increasing the risk of lung cancer. Radon – Radon is an invisible, odourless and tasteless radioactive gas that occurs naturally in soil and rocks. It can cause damage to the lungs and may cause lung cancer. People who work in mines may be exposed to radon. Pollution – Researchers have found a link between lung cancer and exposure to certain air pollutants, such as bye-products of the combustion of diesel and other fossil fuels.

Lung Diseases – Certain lung diseases, such as tuberculosis (TB), increase a person’s chance of developing lung cancer. Lung Cancer tends to develop in areas of the lung that are scarred from TB. Personal Medical and Family History – A person who has had lung cancer once is more likely to develop a second lung cancer compared to a person who never had lung cancer. Brothers, sisters and children of those who have had lung cancer have a slightly higher risk of lung cancer. However, it is difficult to say how much of this excess risk is due to inherited factors and how much is due to passive smoking.

Other Exposures – People with lung diseases caused by breathing in certain chemicals like Saw Dust , Silicon and Barium also have an increased risk of Lung cancer.

Researches continue to study the causes of lung cancer and try to find ways to prevent it. We already know that the best way to prevent lung cancer is to quit (or never start) smoking.

What are the symptoms of Lung Cancer?

  • Unexplained chronic cough.
  • Repeated attacks of lung infection.
  • Breathlessness, wheezing hoarseness.
  • Sputum mixed with blood.
  • Constant chest pain.
  • Loss of appetite or weight loss.
  • Fatigue.

Treating Non Small Cell Lung Cancer:

Patients with Non Small Cell Lung Cancer may be treated in several ways. The choice of treatment depends mainly on the extent of the disease. Surgery is the most common way to treat this type of lung cancer. Radiation therapy and chemotherapy may also be used to slow the progress of the disease and to manage symptoms.

Treating Small Cell Lung Cancer:

Small Cell Lung Cancer spreads quickly. In many cases, cancer cells have already spread in other parts of the body when the disease is diagnosed. In order to reach cancer cells throughout the body, doctors almost always use chemotherapy. Treatment may also include radiation therapy aimed at the tumor in the lung or tumors in other parts of the body (such as in the brain). Some patients have radiation therapy to the brain even though no cancer is found there. This treatment, called prophylactic cranial irradiation (PCI), is given to prevent tumors from forming in the brain. Surgery is part of the treatment for a small number of patients with small cell lung cancer.

The importance of Follow-up Care:

Follow-up care after treatment for lung cancer is very important. Regular checkups ensure that changes are quickly noticed, and if the cancer returns or a new cancer develops, it can be treated as soon as possible. Checkups may include physical exams, chest X-rays or lab tests.
Some of the symptoms mentioned above are quite common in everyday illnesses and do not necessarily indicate cancer. Nevertheless, it is wise to pay heed to these symptoms and seek advice from your doctor. Early detection gives the best choice of cure.

How can Lung Cancer be diagnosed?

To help find the cause of symptoms, a doctor evaluates a person’s medical history, smoking history, exposure to environmental and occupational substances and family history of cancer. After clinical examination, X-ray of the chest is the starting point. It this does not help special x-ray examination called Tomography is undertaken. To confirm the presence of lung cancer, the doctor must examine tissue from the lung. The only way to make the diagnosis of cancer is to examine cells or tissues from the suspected lesion under a microscope by a pathologist, a procedure referred to as biopsy.

Bronchoscopy – The doctor puts a bronchoscope (a thin, lighted tube) into the mouth and down through the windpipe to look into the breathing passages. Through this tube the doctor can collect cells or small samples of tissue.

Staging the Disease:

If the diagnosis is cancer, the doctor wants to know about the stage (or extent) of the disease. Staging is done to find out whether the cancer has spread and if so, to which part of the body. Knowing the stage of the disease helps the doctor plan treatment. Some tests used to determine whether the cancer has spread include:

Cat (or CT Scan) computed tomography – A computer linked to an X-ray machine creates a series of detailed pictures of areas inside the body.

MRI (magnetic resonance imaging) – A powerful magnet inked to a computer makes detailed pictures of areas inside the body.

Radio nuclide scanning – Scanning can show if cancer has spread to other organs such as the liver. The patient swallows or receives an injection of a mildly radioactive substance. A scanner measures and records the level of radioactivity in certain organs to reveal abnormal areas.

What are the treatment options for Lung Cancer?

Treatment depends on a number of factors, including the type of lung (non small cell or small cell lung cancer), the stage of the disease, and the general health of the patient. Many different treatments and combination of treatments are used to treat lung cancer. The three common modes of cancer treatment are Surgery, Radiotherapy and Chemotherapy. Surgery is the common mode of cancer treatment, wherein the Surgeon removes a localized tumor. When the surgeon removes an entire lobe of the lung, the procedure is called a Lobectomy. Pneumonectomy is the removal of an entire lung. The human lung has substantial reserve capacity and removal of a lobe or even one full lung does not severely incapacitate the person.

Chemotherapy is treatment of cancer by drugs. Cancer chemotherapy employs cytotoxic drugs capable of arresting fast cellular growth. Chemotherapy also affects other fast growing and dividing normal cells in the body. The treatment is given in cyclic form once in 3 or 4 weeks, to allow for adequate recovery of normal tissues and to ensure that cancer cells are killed at the same time. Radiation therapy involves subjecting the cancer bearing region to radiation, Ionizing radiation damages or destroys the cancer cells and prevents them from growing and multiplying. Normally the treatment is divided over a period of one month, during which fixed doses of radiation are delivered each day (five days/week.) Radiation affects both normal as well as abnormal tissues. The schedule for radiation is planned in a way that it helps recovery of the normal tissues while ensuring sustained tumor destruction. Chemotherapy and Radiation therapy may cause side effects, but most side effects of radiotherapy and chemotherapy are reversible after treatment is over.