Malignant transformation of the Lung tissue is known as Lung cancer. It is the second commonest form of Cancer known to mankind. Lung cancer is most common form of cancer related death in men and second most common in women. In USA alone 175,000 new cases are expected in a year out of which 90,700 in men and 80,000 in women.
	Lung cancer was extremely rare prior to the advent of cigarette smoking, but increased dramatically as over decades as tobacco smoking increased. However the incidence of lung cancer in developed coutries is dropping due to public awareness, still it remains the most common form of cancer in men and fifth common form of cancer in women.

• Smoking
• Passive smoking
• Asbestos fibers
• Radon gas
• Genetic predisposition
• Lung disease
• Air Pollution
• Prior history of lung cancer

• Smoking
  Smoking, particularly of cigarettes is the commonest cause of cancer of lungs. Cigarette smoke is known to contain over 60 carcinogens like radioisotopes from the radon decay sequence, nitrosamine, and benzopyrene. Plus, the action of nicotine depresses the immune response to malignant growths.
  Chance of developing cancer is directly proportional to the duration of time the person continues to smoke and quantity of cigarettes smoked. As soon as the person stops smoking these chances decrease gradually as damage to the lungs is repaired and noxious wastes are gradually vacated.
• Passive Smoking
  Non smokers inhaling tobacco smoke exhaled by smokers is known as passive or indirect smoking. Non smokers sharing residence with smokers have about 24% more chances of developing lung cancer than other non smokers.
• Asbestos fibers
  Asbestos workers who do not smoke have a five times greater risk of developing lung cancer than non-smokers, and those asbestos workers who smoke have a risk that is 50 to 90 times greater than non-smokers. Asbestos is a type of silicon fiber which can permanently be launched in the lungs, previously it was used in developing thermal and acoustic insulation. Currently its use is banned or limited in many countries world wide.
• Radon gas
  Radon gas is a natural decay product of uranium it is invisible and odorless. Radon gas can travel up through soil and enter homes through gaps in the foundation, drains, or other openings. A study done by the U.S. Environmental Protection Agency suggests that one out of every 15 homes in the U.S. contains dangerous levels of radon gas.
• Genetic predisposition
  Research has shown that a localized region on the long (q) arm of the human chromosome number 6 is likely to contain a gene that conferring an increased susceptibility to the development of lung cancer in smokers, how ever not all smokers develop cancer, suggesting an individualistic genetic susceptibility. Studies have shown that smokers and non-smokers of relatives who have had lung cancer are more likely to develop cancer of lung.
• Lung disease
  History of COPD (Chronic Obstructive Lung Diseases) is associated with somewhat increased possibility of developing lung cancer. Lung cancer survivors have a greater risk than the general population of developing a second lung cancer.
• Air Pollution
  Air pollution, from vehicles, industry, and power plants, can raise the likelihood of developing lung cancer in exposed individuals.

• Small Cell Lung Cancer (SCLC)
  It is also known as o oat cell carcinoma due to the shape of its cell. SCLC comprises of 20% of all lung cancer. It is strongly associated with cigarette smoking not common amongst non smokers. They tend to spread and grow fast; they metastasize rapidly within the body and are most often discovered after they have spread extensively.
• Non Small Cell Lung Cancer (NSCLC)
  NSCLC comprises about 80% of all lung cancer cases. It has three main types based on the type of cells found in its tumor.
  1. Adenocarcinoma is commonest type of NSCLC and comprises up to 50% of NSCLC. It is also found commonly amongst non-smokers who develop lung cancer. Most often it affects peripheral, areas of the lungs. Bronchioloalveolar carcinoma is a subtype of Adenocarcinoma.
  2. Squamous cell carcinomas they account for about 30% of NSCLC. They are also known as epidermoid carcinomas. They mostly affect the central chest area in the bronchi.
     Large cell carcinomas, also known as undifferentiated carcinomas, are the least common type of NSCLC.
     Mixtures of different types of NSCLC are also seen.
     Other types of cancers less common than NSCLC and SCLC; together comprise only 5-10% of lung cancers.
  3. Bronchial carcinoids account for up to 5% of lung cancers. These tumors are usually small and affect most commonly persons under 40 years of age. They most often not related to smoking and generally grow and spread slowly.

• No symptoms 25% of lung cancer is detected on routine chest x-ray or CT scan as a single small mass. Such patients most often do not present with any symptoms.
• Cancer invading the lung tissue may interfere with breathing causing
  • Cough
  • Shortness of breath
  • Wheezing
  • Chest pain
  • Coughing up of blood (Hemoptysis)
  • Cyanosis, a bluish color of the skin
  • Changes in the tissue of the nail beds, known as clubbing,
• Obstruction of air way may cause lung collapse leading to infections like pneumonia and abscess in obstructed area
• Nerve affections may cause shoulder pain radiating along the arm (Pancoast's syndrome). Paralysis of the vocal cords can cause hoarseness of voice.
• Involvement of the esophagus may cause difficulty in swallowing (Dysphagia).
• Symptoms related to metastasis
  • Lung cancer that has spread to the bones may produce excruciating pain at the sites of bone involvement.
  • Spread to the brain may cause a number of neurologic symptoms like blurred vision, headaches, symptoms of stroke, etc.
• Paraneoplastic symptoms
• Nonspecific symptoms

One should consult a health care provider if they have:
• A new persistent cough or worsening of an existing chronic cough
• Blood in sputum
• Persistent bronchitis
• Repeated respiratory infections
• Chest pain
• Unexplained weight loss
• Fatigue
• Breathing difficulties like shortness of breath or wheezing

• History and clinical examination may reveal signs and symptoms associated with lung cancer.
• Chest x-ray: This may reveal an obvious mass, widening of the mediastinum (suggestive of spread to lymph nodes there), atelectasis (collapse), consolidation (infection) and pleural effusion.
• Bronchoscopy / CT scan / MRI or Ct scan guided biopsy is often done to confirm and identify the tumor type, size and location.
• Positron emission tomography (PET) is done to identify the typr of tumor cell and to know if the tumor tissue is actively growing.
• Sputum cytology is done to pathologically confirm the presence of tumor cells.

Stage of a lung cancer tumor defines and refers to
• Extent to which a cancer has spread in the body.
• Evaluation of a tumor's size as well as the presence or absence of metastases

Staging helps determine how a particular tumor should be treated and is also critical in estimating the prognosis of a given patient. Higher-stage tumors generally have a worse prognosis than lower-stage tumors.

Common treatment options available for lung cancer are Surgery, Chemotherapy, and Radiation. A combination of therapies from amongst three may also be resorted to. The treatment would largely depend upon the cancer's specific cell type, how far it has spread, and the patient's current health status.

Surgery
Surgery is resorted to in those cases where the lesion is localized and can be effectively treated with surgery. The current health status of the patient is also important it should be good enough to sustain surgery. Procedures include wedge excision (removal of part of lobe), lobectomy (one lobe), bilobectomy (two lobe), and pneumonectomy (whole lung).

Chemotherapy
SCLC is primarily treated with chemotherapy. Primary chemotherapy is also given in cases where NSCLC shows metastasis. Chemotherapy is often used as an adjuvant therapy after surgery to improve the chances of recovery.

Radiotherapy
Radiotherapy is often used along with chemotherapy, for patients not suited for surgery. Interventional radiology a popular method resorted to is done by inserting a small heat probe into the tumor to kill the tumor cells.

The role of Homeopathic medicines in treating patients with lung cancer is primarily as a palliative medicine. Homeopathic medicines can give good relief by decreasing the intensity and severity of symptoms. The pain, discomfort, can be managed with homeopathic medicines.

Homeopathic medicines do not have any side effects and when used along with chemotherapy it helps to control the side effects of chemotherapy drugs and makes the therapy bearable.

The inherent action of homeopathic medicines is to improve the immunity of the person and increase the self healing capacity of the body. This helps the patient to become more resistant to secondary infections. This also helps to control the spread and progress of disease. Post surgery the recovery is faster and better and the chances of recurrence too can be reduced.

All in all the role of homeopathic medicines is to make the patient more comfortable and live a relatively healthier life.

Survival rate for patients suffering form lung cancer is poor as compared to other cancer patients. The overall 5 year survival rate is about 15% in most cases.

Prevention is better than cure in this case. It is the most effective way of fighting lung cancer.

Cessation of smoking is an important step for eliminating risk of developing lung cancer. It also results in reduction of passive smoking. Smoking in pubic places is banned in many countries across the globe. Elimination and prohibiting the use of carcinogenic toxins is done in most countries.