What is lung cancer?

Lung cancer, also known as lung carcinoma,  is a malignant lung tumor characterized by uncontrolled cell growth in lung tissues. This growth can spread beyond the lung by metastasizing to nearby tissue or other parts of the body The cancers that begin in the lungs primarily are known as lung cancers.

Signs and symptoms

Signs and symptoms which may suggest lung cancer include: 

*Respiratory symptoms: coughing, coughing up blood, wheezing, or shortness of breath

*Systemic symptoms: weight loss, weakness, fever, or clubbing of the fingernails

* Symptoms due to the cancer mass pressing on adjacent structures: chest pain, bone pain, superior vena cava obstruction, or difficulty swallowing.

Risk for cancer increases:-

Smoking

*Smoking-Smoking is by far the largest contributor to lung cancer.

*Passive smoking- inhaling smoke from someone else's smoking is a cause of lung cancer in nonsmokers. 

Radon gas

Radon is a colorless and odorless gas generated by the decomposition of radioactive compounds like Uranium which is found in the earth's crust. The decay products of radiation ionize genetic material and cause mutations that sometimes turn cancerous. Radon is the second most common cause of lung cancer.

Asbestos

It can cause a variety of lung diseases including lung cancer. Smoking and asbestos have synergistic effects on the development of lung cancer. In smokers who work with asbestos, the risk of lung cancer increases 45 times compared to the general population.

Air pollution

There are different types of air pollutants, such as gases (ammonia, carbon monoxide, sulfur dioxide, nitrous oxides, methane, and chlorofluorocarbons), particles (both organic and inorganic), and biological molecules. Air pollution can cause illness, allergies, and even death in humans; it can also cause harm and also may cause lung cancer.

Genetics

About 8% of lung cancer is caused by hereditary factors. In family members of people diagnosed with lung cancer, the risk doubles, probably due to a combination of genes.

Diagnosis:-

Lung cancer often appears as a solitary pulmonary nodule on a chest x-ray or CT scan done for an unrelated reason. The definitive diagnosis of lung cancer is based on histological examination of the suspicious tissue in the context of the clinical and radiological features. 

Clinical practice guidelines recommended more frequently for monitoring pulmonary nodules. CT imaging should not be used longer or more frequently than directed, as extended surveillance exposes people to more radiation and is expensive.

Tests may include:

• Imaging tests. An X-ray image of your lungs may reveal an abnormal mass or nodule. A CT scan can reveal small lesions in your lungs that might not be detected on an X-ray.

• Sputum cytology. If you have a cough and are producing sputum, looking at the sputum under the microscope can sometimes reveal the presence of lung cancer cells.

• Tissue sample (biopsy). A sample of abnormal cells may be removed in a procedure called a biopsy.

Types of lungs cancer:-

*Non-small-cell lung carcinoma (NSCLC)

About 80% to 85% of lung cancers are NSCLC. The main subtypes of NSCLC are adenocarcinoma, squamous cell carcinoma, and large cell carcinoma.

* Small-cell lung carcinoma(SCLC)

About 10% to 15% of all lung cancers are SCLC and it is sometimes called oat cell cancer. 

How to prevent lungs cancer:-

*Smoking ban- Although industrial and household carcinogens have been identified and banned in most countries, smoking is still widespread. Eliminating smoking is a primary goal in lung cancer prevention, and quitting smoking is an important preventive tool in this process.

*Avoid radon exposure-Radon is an important cause of lung cancer. You can reduce your exposure to radon by having your home tested and treated, if needed. For more information, see Radon and Cancer.

*Avoid or limit exposure to cancer-causing agents-Avoiding exposure to known cancer-causing agents, in the workplace and elsewhere, may also be helpful (see  Lung Cancer Risk Factors). When people work where these exposures are common, they should be kept to a minimum.

*Eat a healthy diet-A healthy diet with lots of fruits and vegetables may also help reduce your risk of lung cancer. Some evidence suggests that a diet high in fruits and vegetables may help protect both smokers and non-smokers against lung cancer. But any positive effect of fruits and vegetables on lung cancer risk would be much less than the increased risk from smoking.

Trying to reduce the risk of lung cancer in current or former smokers by giving them high doses of vitamins or vitamin-like drugs has not been successful so far. In fact, some studies have found that supplements of beta-carotene, a nutrient related to vitamin A, appear to increase the rate of lung cancer in these people.

*Screening- Cancer screening tests use medical tests to detect diseases in large groups of people who do not have symptoms. For people at high risk of developing lung cancer, computed tomography (CT) scanning can detect cancer and provide the person with options to respond to it in a life-prolonging way. This form of screening reduces the chance of death from lung cancer by an absolute amount of 0.3% (relative amount 20%). High-risk individuals are those ages 55 to 74 who have smoked the equivalent amount of one pack of cigarettes per day for 30 years, including the length of time in the past 15 years.

*Other activities:- Long-term use of supplemental vitamin A, vitamin C,  vitamin D, or vitamin E does not reduce the risk of lung cancer. Some studies have found that vitamins A, B, and E can increase the risk of lung cancer in those with a history of smoking.

Some studies suggest that people who eat diets with a higher proportion of vegetables and fruits tend to have a lower risk,  but this may be due to confounding factors, and the lower risk is actually due to the association of a high fruit and vegetable diet with less smoke.  Several rigorous studies have not shown a clear association between diet and lung cancer risk, although meta-analysis explaining smoking status may show benefits of a healthy diet.

Treatment of lung cancer:-

* Surgery

* Chemotherapy

* Targeted therapy for lung cancer

* Immunotherapy

* Radiation

History of lung cancer:-

Before the early part of the 20th century, lung cancer was considered a very rare disease, and all malignant lung tumors were treated identically. [61] Radical surgical resection was the only effective intervention available for lung cancer before the 1940s when the era of cytotoxic chemotherapy began. modern.

It was not until 1962 that small cell lung carcinoma (SCLC), then called "oat cell carcinoma", was recognized for its unique biological behavior, including a much higher frequency of generalized metastases at presentation and exquisite sensitivity to cytotoxic chemotherapy and radiation. 

Early studies suggested that patients with small cell lung carcinoma (SCLC) performed better when they received chemotherapy or radiation than when they received surgical treatment.  While this approach to treating SCLC remains the current standard of care, the role of surgery in SCLC is being reexamined, and recent studies indicate that surgery may improve outcomes in some patients with early-stage SCLC and combined forms of SCLC and NSCLC.

FAQs

How long can you live with lung cancer?

The 5-year survival rate for all people with all types of lung cancer is 21%. The 5-year survival rate for men is 17%. The 5-year survival rate for women is 24%. The 5-year survival rate for NSCLC is 25%, compared to 7% for small cell lung cancer.

Can Lung Cancer kill you?

Lung cancer is the most common cancer and the most common cause of cancer death in the world today [World Health Organization, 2013]. Despite advances in lung cancer detection, pathologic diagnosis, and therapy, many patients still develop advanced, incurable, and progressively fatal diseases.

How many people die from lung cancer in India?

The overall estimated lung cancer mortality in India in 2012 was 63,759, making it the third most common cause of cancer-related mortality in India after breast and cervical cancer.

Is lung cancer always fatal?

Even though lung cancer remains an extremely deadly type of cancer, presently there is great hope to reduce the fatalities due to this disease