Lung Cancer - Symptoms, Causes, and Stages

Signs and Symptoms of Lung Cancer in Humans  

Lung cancer is a form of cancer that begins with abnormal cell development in the lungs and tends to advance with no apparent signs in its early stages. In India, an estimated 72,510 new cases (5.8% of all cancers) and 66,279 deaths (7.8% of all cancer deaths) occur due to lung cancer yearly.  

Though the disease is more common among smokers, it can happen to non-smokers as well. However,  the symptoms of lung cancer in females and males can differ based on their age, gender, and genetics.  

Prompt detection and treatment are key to improving survival rates. Thus, it is necessary to be aware of the warning signs, causes and stages of this disease.  

Table of Contents 

What is Lung Cancer? 

Symptoms of Lung Cancer 

Causes of Lung Cancer 

Stages of Lung Cancer 

Frequently Asked Questions 

What is Lung Cancer?  

Lung cancer is a disease that results from the abnormal growth of lung cells. These cells normally divide to form newer versions as part of their normal function. However, mutations cause cells to divide abnormally, even when not needed.  

This abnormal division of damaged cells leads to the growth of masses or tumours. Lung cancer usually develops in the breathing tubes (bronchi or bronchioles) or the small air bladders (alveoli). The cancers that arise in other tissues and metastasize to the lungs are most commonly named according to their point of origin.  

Symptoms of Lung Cancer 

When it comes to lung cancer, many people may not experience major symptoms until the disease reaches its advanced stage, while others may face a few symptoms in the early stages. The following are the symptoms of lung cancer in men and women: 

• An unrelenting cough that either continues or worsens 
• Trouble breathing  
• Chest pain or discomfort 
• Wheezing (a whistling sound during breathing) 
• Coughing up blood 
• A hoarse voice 
• Poor appetite 
• Involuntary loss of weight 
• Unexplained exhaustion 
• Shoulder pain 
• Lumps, discolouration, or skin ulcers. 
• Face, neck, arm, and upper chest swelling 
• Small pupil and droopy eyelid on one side of the face and little or no sweating on one side 

Causes of Lung Cancer 

Although the actual reason for lung cancer is unknown, there are various causes that enhance the possibility of lung cancer development: 

• Smoking Tobacco 

The primary reason for lung cancer, responsible for over 70% of cases globally, is smoking. Tobacco smoke has more than 60 carcinogenic chemicals that harm lung cells, causing mutations. People who enjoy smoking cigarettes, bidis, cigars, pipe tobacco, snuff (tobacco powder), and chewing tobacco leaves also pose a risk of increasing lung cancer.

• Exposure to Radon Gas 

Radon is a naturally occurring radioactive gas in soil, rock, and groundwater. It penetrates buildings, especially basements, and is hazardous when inhaled over extended periods of time. Radon exposure is the second most common cause of lung cancer after smoking.  

Radon lung cancer symptoms often include persistent cough, shortness of breath, chest pain, and unexplained weight loss.  

• Occupational Exposure to Hazardous Substances 

Some occupations expose individuals to carcinogenic chemicals and substances that can heighten lung cancer risk. Some of the common occupational hazards that can lead to lung cancer include asbestos, which is often used in construction materials and insulation. This is a severe threat as it can lead to long-term lung problems when inhaled.  

Workers in industries such as mining and manufacturing can also be exposed to arsenic, beryllium, cadmium, and nickel, which are all established carcinogens that can cause lung cancer after long-term exposure.  

Coal processing industries also emit coal and coke fumes, which contain harmful chemicals that irritate the lungs and can cause cancer. Silica dust, commonly found in mining, construction, and sandblasting operations, is another major cause.  

• Air Pollution 

Prolonged exposure to heavy air pollution, especially diesel exhaust smoke, has been associated with a higher lung cancer risk. Airborne pollutants have carcinogens that, with prolonged exposure, can destroy lung tissue. 

• Genetic and Family History 

Though less frequent, lung cancer may develop in individuals with no identified risk factors. A history of lung cancer in the family can be a sign of genetic susceptibility, increasing the likelihood of developing the disease. 

• Past Radiation Therapy 

People who have had radiation therapy to the chest for other cancers, including breast cancer or Hodgkin's lymphoma, are at higher risk of developing lung cancer in later life. 

• Chronic Lung Diseases 

Diseases like chronic obstructive pulmonary disease (COPD) and pulmonary fibrosis increase the risk of lung cancer. These diseases result in long-term inflammation and injury to lung tissue, which can result in cancerous changes. 

Stages of Lung Cancer 

Here's an overview of every stage, listing the most important lung cancer symptoms and treatment options advisable for each. 

• Lung Cancer – Stage 1 

The tumour during stage I lung cancer exist in the lung only and is found to be fairly small (less than 4 centimetres) in size. At this stage, the cancer does not affect nearby lymph nodes or elsewhere within the chest.  

This early stage rarely has visible symptoms, making it difficult to notice without regular screenings. Some individuals might experience lung cancer symptoms in the early stage, like cough, shortness of breath, or a slight decrease in appetite, but these are less common.  

Most patients at this stage may not require chemotherapy, targeted therapy, or immunotherapy. 

• Lung Cancer - Stage 2 

In the second stage of lung cancer, the tumour becomes more than 4 centimetres in size and can spread to adjacent lymph nodes but not outside the lung. The symptoms become more apparent and may involve chronic or increased coughing with blood or phlegm, chest discomfort, shortness of breath, and hoarseness.  

Fatigue, weight loss, and frequent respiratory infections are also possible stage 2 lung cancer symptoms. Treatment typically includes surgery followed by chemotherapy, targeted therapies, or immune therapies to eradicate any remaining cancer cells. 

• Lung Cancer Stage - 3 

In Stage 3 lung cancer, cancer grows to lymph nodes in the chest or develops large tumours involving the nearby lymph nodes. Symptoms become more intense and might involve a chronic cough, shortness of breath, chest discomfort, hoarseness, and blood-tinged sputum.  

Other signs include fatigue, loss of weight, and poor appetite, which are characteristic stage 3 lung cancer symptoms. Treatment in the third stage commonly consists of a combination of therapies, such as chemotherapy, surgery, radiation therapy, targeted therapies, and immune therapies, to control the spread of the cancer and alleviate symptoms. 

• Lung Cancer - Stage 4 

In stage 4 lung cancer, the cancer has metastasized outside the chest to other locations in the body, including the other lungs, bones, brain, or adrenal glands. It is characterized by serious symptoms, such as a chronic cough, chest pain, shortness of breath, weakness, and loss of appetite.  

Symptoms of stage 4 lung cancer may also involve pain or neurological changes if the cancer has developed in the bones or brain. Treatment methods for Stage four include chemotherapy, targeted therapies, or immune therapies. 

Lung cancer is a complex and life-threatening condition that may appear in a variety of symptoms, from non-stop coughing to shortness of breath. Learning about the symptoms of lung cancer, particularly the initial stages, can be helpful for people to seek medical care earlier, enhancing the possibility of effective treatment.  

To help you meet the treatment expenses for lung cancer, Star Health Insurance provides the Star Cancer Care Platinum Insurance Policy. This plan gives you complete coverage for cancer treatments, including lung cancer, to ensure that you and your family are well-protected financially in your fight against cancer.